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Tuesday, July 31, 2012

Kirk or Wesley? You Decide. But Hurry!

The above frames were taken from the two versions of NASA's video, Curiosity's "Grand Entrance" to Mars. One version is hosted by William Shatner (left) and the other is hosted by Wil Wheaton (right). Image Credit: NASA

To help promote the upcoming landing of NASA's Mars Science Laboratory / Curiosity rover. NASA has released not one, but two versions of its new video, Curiosity's "Grand Entrance" to Mars. The 4-minute 12-second videos are the same except for their host and narrator. With a nod to the fans of the Star Trek franchise, one video is hosted by William Shatner (who played Captain James T. Kirk) and the other video is hosted by Wil Wheaton (who played Wesley Crusher). Links to these videos abound on the Internet. The ones presented below are on Youtube.com.

CLICK HERE to watch the video hosted by William Shatner.

CLICK HERE to watch the video hosted by Wil Wheaton.

Regardless of your possible love/hate relationship with either (or both) of the represented Star Trek characters, you are sure to learn a lot about this most ambitions mission to the Red Planet to date. But don't wait. Run your video of choice now and learn all that you can.

On August 5th, beginning 8:30 PM PDT / 11:30 PM EDT / 15:30 UTC, NASA will broadcast the landing coverage online. To join in, go to this URL, mars.jpl.nasa.gov/msl/participate .

And now, the mission particulars...

The Mars Science Laboratory / Curiosity rover mission is managed for NASA’s Science Mission Directorate, Washington, D.C., by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena (Caltech). More information about Curiosity is online at www.nasa.gov/msl and mars.jpl.nasa.gov/msl . You can follow the mission on Facebook at: www.facebook.com/marscuriosity and on Twitter at: www.twitter.com/marscuriosity .

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CORRECTION: 2012 Alpha Capricornids


The above image is a chart of the constellation Capricornus, presented by the International Astronomical Union (IAU). The location of the radiant point of the Alpha Capricornid meteor shower is indicated by the radiating red lines. Image Credit: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)

Apologies, Dear Reader. This article was originally posted with wrong image. We are now re-posting with the correction. Please enjoy.

This Wednesday/Thursday, August 1st/2nd, marks the peak of the Alpha Capricornid meteor shower. Meteors from this shower will appear to originate from a point in the constellation of Capricornus (RA 20h 36m, Dec -10°).

The shower runs from July 15th through August 25th and has a rate of about 8 per hour. Though the rate is low, the shower features relatively bright meteors and some fireballs. And this fact is critical for observers this year, since the shower will be fighting a full moon sitting smack dab in the middle of the radiant. Observers, your best chance to see meteors is to avert your eyes from the bright moon and look toward a portion of the sky moving outward from the radiant. This observing method works better if you are observing with two or more people. In this way each of you can cover a different portion of the sky and keep each other verbally apprised of your sightings without taking your eyes off the meteoric prize. And even though you are dealing with a bright moon, please do your best to seek out a dark-sky location for your observing session.

The Alpha Capricornids were discovered in 1871 by Hungarian astronomer Miklos von Konkoly-Thege (1842-1916). Parent body is comet 169P/NEAT, discovered March 15, 2002 by NASA's Near-Earth Asteroid Tracking (NEAT) program. The NEAT program was run by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California from December 1995 until April 2007.

To learn more about meteors, comets, and asteroids, check out these URLs.

NASA's All Fireball Network (fireballs.ndc.nasa.gov), part of NASA's Meteoroid Environment Office, www.nasa.gov/offices/meo .

Asteroids, Comets, Meteorites (a NASA Asteroid Watch article): www.jpl.nasa.gov/asteroidwatch/asteroids-comets.cfm

NASA's Near-Earth Object (NEO) Program coordinates NASA-sponsored efforts to detect, track and characterize potentially hazardous asteroids and comets that could approach the Earth. To learn more, visit the home page of NASA's Near-Earth Object Program: neo.jpl.nasa.gov .

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MSL/Curiosity: Six Days From Landing

The above image is an artist's concept of NASA's Mars Science Laboratory (MSL) spacecraft during its cruise phase between launch and final approach to Mars. The spacecraft includes a disc-shaped cruise stage (on the left) attached to the aeroshell. The spacecraft's rover (Curiosity) and descent stage are tucked inside the aeroshell. Image credit: NASA/JPL-Caltech

On July 28th at about 10:00 PM PDT (1:00 AM EDT on July 29th), NASA's Mars Science Laboratory (MSL) spacecraft performed a scheduled flight-path adjustment, possibly its last before reaching Mars. But two additional planned adjustment opportunites remain if needed.

The spacecraft will deliver the mission's car-size rover, Curiosity, to a landing target inside Gale Crater and near the central peak, formerly known as "Mount Sharp," but recently named "Aeolis Mons" by the International Astronomical Union (IAU). The landing is scheduled to occur at about 10:31 PM PDT on August 5th (1:31 AM EDT on August 6th). Upon landing, the Curiosity rover will begin its two-year prime mission studying whether the area has ever offered environmental conditions favorable for life.

The recent thruster burn shifted the atmosphere entry point by about 13 miles (21 kilometers) west, toward the target, and lowered the velocity by about one-fortieth of one mile per hour (one centimeter per second). Curiosity will enter Mars' atmosphere at a speed of about 13,200 mph (5,900 meters per second).

The descent through Mars' atmosphere and down to the surface will employ techniques that allow for a combination of a smaller target area and a heavier landed payload, than were possible for any previous Mars mission. These innovations, if successful, will place a well-equipped mobile laboratory into a locale especially well-suited for its mission of discovery.

As of July 30th, the MSL spacecraft had carried the rover Curiosity had traveled about 343 million miles (555 million kilometers) of its 352-million-mile (567-million-kilometer) flight to Mars.

On August 5th, beginning 8:30 PM PDT / 11:30 PM EDT / 15:30 UTC, NASA will broadcast the landing coverage online. To join in, go to this URL, mars.jpl.nasa.gov/msl/participate .

And now, the mission particulars...

The Mars Science Laboratory / Curiosity rover mission is managed for NASA’s Science Mission Directorate, Washington, D.C., by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena (Caltech). More information about Curiosity is online at www.nasa.gov/msl and mars.jpl.nasa.gov/msl . You can follow the mission on Facebook at: www.facebook.com/marscuriosity and on Twitter at: www.twitter.com/marscuriosity .

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Dawn and Vesta, the Long Goodbye

The above image shows the three touching impact craters of different sizes on Vesta's surface, that are reminiscent of the shape of a snowman. This feature is one of Vesta's most striking. North is to the lower right in this orientation. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

On July 30th, the chief engineer for NASA's Dawn mission, Marc Rayman, reported that Dawn had completed the final phase of its exploration of Asteroid 4 Vesta. On July 25th at 9:45 AM PDT (12:45 PM EDT), the Dawn spacecraft cranked up its ion propulsion system and began its gradual, month-long departure. Dawn is basically reversing the process it followed into orbit last year.

The last major study was the second high-altitude mapping orbit (HAMO2), in which Dawn imaged Vesta's surface on the day side and then transmitted data back to Earth while on the night side, repeating this cycle every 12.3 hours — the length of each Vesta orbit during that phase. This process allowed Dawn to gather full coverage of Vesta's illuminated surface every five days.

The mission team reports that Dawn worked flawlessly in its tasks and was able to map the surface six times — with more than 4,700 images. Two of the imaging passes were vertical and four of the passes were angled, allowing the mission team to create three dimensional images when the perspectives are combined.

The first high-altitude mapping orbit (HAMO1) ran from September through October 2011. But Vesta has seasons, of a sort, and running this second mapping will allow the mission team to compare the data and note the specific differences in the seasons on Vesta.

In addition to the images, Dawn obtained nearly nine million spectra (over twice the amount of HAMO1) with its visible and infrared mapping spectrometer (VIR). These will allow scientists to learn about the nature of Vesta's minerals.

Dawn's low altitude mapping orbit (LAMO) phase, between HAMO1 and HAMO2, allowed the mission team to more carefully study Vesta's gravity field and, from that, derive more information about Vesta's composition. The LAMO phase also Dawn's gamma ray and neutron detector (GRaND) to collect its best data on composition of Vesta's surface and subsurface. And the GRaND data gathering continued during HAMO2, adding to the wealth of Vesta information.

While Dawn is primarily focused on ion thrusting, it will stop four times during its ascent, to take Vesta surface images for navigational purposes, much in the same way the spacecraft did during its gradual descent into Vesta orbit last year.

The Dawn mission team expects that on August 26th (my birthday), Dawn will be far enough away from Vesta that its orbit will transition to a solar one. The little spacecraft will then officially begin the journey to dwarf planet Ceres, where it should arrive in February 2015.

And now, the mission particulars...

NASA's Dawn mission to Vesta and Ceres is managed by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington D.C. UCLA is responsible for overall Dawn mission science. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. Orbital Sciences Corporation (OSC) in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. The Dawn framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The Framing Camera project is funded by the Max Planck Society, DLR, and NASA/JPL. The California Institute of Technology in Pasadena manages JPL for NASA.

To view the new Vesta images and for more information about Dawn, visit: www.nasa.gov/dawn and dawn.jpl.nasa.gov .

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Monday, July 30, 2012

NuSTAR: Bumps in the Road

The above image is the cover page of report of Aldridge Commission, Report of the President's Commission on Implementation of United States Space Exploration Policy, 2004. Image Credit: NASA / Aldridge Commission

We now continue our review of NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission, which launched June 13th. In this outing we continue on the road to final approval. And along the way we find some bumps in the road…

The Vision for Space Exploration

On January 14, 2004, U.S. President George W. Bush announced a plan for space exploration called the Vision for Space Exploration (VSE). The VSE sought to implement a sustained and affordable human and robotic program to explore the solar system and beyond; extend human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations; develop the innovative technologies, knowledge, and infrastructures both to explore and to support decisions about the destinations for human exploration; and to promote international and commercial participation in exploration to further U.S. scientific, security, and economic interests. In pursuit of these goals, the Vision called for the space program to complete the International Space Station by 2010; retire the Space Shuttle by 2010; develop a new Crew Exploration Vehicle (later renamed Orion) by 2008, and conduct its first human spaceflight mission by 2014; explore the Moon with robotic spacecraft missions by 2008 and crewed missions by 2020, and use lunar exploration to develop and test new approaches and technologies useful for supporting sustained exploration of Mars and beyond; explore Mars and other destinations with robotic and crewed missions; pursue commercial transportation to support the International Space Station and missions beyond low Earth orbit.

Spring 2006

By the beginning of 2006, NuSTAR was slated for a 2009 launch. More than two dozen graduate and postdoctoral students were deeply involved. And project expenditures had exceeded $7.5 million. The project team was working around the clock on the project's confirmation review, tying up the loose ends of the process.

But the NuSTAR project could not operate in a vacuum, untouched by events and circumstances without and within NASA. As time passed, NASA was affected more and more by the mandates of the VSE. Eventually, a panel for the National Research Council (NRC) was tasked with assessing the impact of the VSE in the light of the NASA budget proposed Fiscal Year 2007. The NRC panel concluded that the budget provided the agency with insufficient funds to allow it to meet all of its VSE mandates while remaining strong in science. According to one statement in the report, "NASA is being asked to accomplish too much with too little."

The panel's message seemed to be in agreement with NASA's own assessment. In February, NASA announced that, in order to meet the mandates laid out in the VSE, it would have to scale back or eliminate many of its science projects. Specifically, science-program cutbacks of $3 billion over 5 years would be needed.

The cutbacks applied not only to funding for existing programs, but funding for future programs as well. And one of those affected future programs was NuSTAR. As the project team worked long hours to complete its confirmation review, they learned in a televised press briefing that NuSTAR had been cancelled.

The change was immediate. The NuSTAR project went from full funding one day to zero funding the next. And since the news came with no advance warning, there was not time to develop contingencies or to substitute funding from other sources. The project team was immediately dispersed to search for work and academic programs elsewhere.

To be continued.

And now, the mission particulars...

NuSTAR is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA's Jet Propulsion Laboratory, also in Pasadena, for NASA's Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corporation, Dulles, Virginia. Its instrument was built by a consortium including Caltech; JPL; the University of California, Berkeley (UC Berkley); Columbia University, New York; NASA's Goddard Space Flight Center, Greenbelt, Maryland; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, California; and ATK Aerospace Systems, Goleta, California. NuSTAR will be operated by UC Berkeley, with the Italian Space Agency providing its equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University, Rohnert Park, California. NASA's Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA. For more information on the NuSTAR mission, visit 
www.nasa.gov/nustar and http://www.nustar.caltech.edu/ .


To learn more about the High Energy Focusing Telescope (HEFT), visit www.srl.Caltech.edu/HEFT .

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Old Tech: Baker-Nunn Camera


 The above image shows an operational Baker-Nunn camera. Image Credit: NASA

The Baker-Nunn camera was a large camera developed for tracking Earth satellites. The camera was named for its designers, American optical designer James G. Baker (1914-) and American engineer Joseph Nunn (1905-1968).

In 1956, Baker and Nunn collaborated to design and manufacture the camera. Each unit consisted of a very precise tracking system combined with an unusually large, wide-field camera for photographing large areas of the sky. Joseph Nunn was responsible for designing the mechanical elements, while Dr. Baker worked on the camera. The optics were fabricated by the Perkin-Elmer Corporation, and the camera was assembled by Boller and Chivens.

The Baker-Nunn optical design was successor to Baker-Schmidt. In 1940, Baker modified the Schmidt camera design to include a convex secondary mirror, which reflected light back toward the primary. A photographic plate was then installed near the primary, facing the sky. This design is called the Baker-Schmidt camera.

In Baker-Nunn, the camera's corrector plate was replaced with a small triplet corrector lens closer to the focus of the camera. Instead of a photographic plate, 55 mm Cinemascope film was used.

The Baker-Nunn camera was found to be a vital tool at the beginning of the US/Soviet space race, providing visual tracking data on the Soviet Union's Sputnik I satellite, which launched October 4, 1957.

Twelve Baker-Nunns were commissioned and used by the Smithsonian Astrophysical Observatory for their global satellite-tracking program, also known as the STP network. The network used the Baker-Nunn cameras from about August 1958 to the mid 1970s. Each unit designed for the network had a focal ratio of f/0.75 with a 20-inch aperture – each instrument weighed 3.5 tons and included a multiple axis mount, allowing it to follow satellites in the sky. At least one of the cameras was later refurbished for use in the Asteroid tracking program.

From One Era of Optical Tracking to the Next...

While I would not say there was a direct line of descent from the Baker-Nunn cameras and those cameras used by NASA's All Sky Fireball Network, I would at least say the two are kindred and that the former provided inspiration for the latter. Particularly since at least one Baker-Nunn was later repurposed for asteroid tracking.

The NASA All-sky Fireball Network is a network of cameras set up by the NASA Meteoroid Environment Office (MEO) with the goal of observing meteors brighter than the planet Venus, which are called fireballs.  The collected data will be used by the MEO in constructing models of the meteoroid environment, which are important to spacecraft designers.

The network currently consists of 8 cameras, 6 of which are placed in locations in north Alabama, north Georgia, southern Tennessee, and southern North Carolina.  The remaining 2 are located in southern New Mexico. The network is growing all the time, with plans to place a total of 15 cameras in schools, science centers, and planetaria in the United States, predominantly east of the Mississippi River, where there are few such systems. 

Cameras in the network are specialized black and white video cameras with lenses that allow for a view of the whole night sky overhead.

The cameras have overlapping fields of view, which means that the same fireball can be detected by more than one camera.  This allows managers to calculate the height of the fireball and how fast it is going.  They can even work out the orbit of the meteoroid responsible for creating the fireball, which gives astronomers clues about whether it came from a comet or an asteroid.  If the fireball is traveling slow enough, and makes it low enough, it is possible that it can survive to the ground as a meteorite.

To learn more about the program, visit NASA's All Fireball Network (fireballs.ndc.nasa.gov), part of NASA's Meteoroid Environment Office, www.nasa.gov/offices/meo .

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Incoming CME from July 28th Flare

The above X-ray image of the sun is a fairly recent one, taken on July 25th at 13:40 UTC (9:40 AM EDT July 24th) by the GOES-15 satellite. The bright region in the lower left is Active Region 1532 (AR 1532). The bright spot just to the right is AR 1530. Image Credit: NOAA

The folks at NASA's Goddard Space Weather Lab report that the M6-class solar flare from July 28th did, in fact, produce a coronal mass ejection (CME) after all. The flare had erupted from Active Region 1532 (AR 1532) around 21:02 UTC (5:02 PM EDT).

Forecasters say that because AR 1532 was not turned toward Earth (and still is not as of yet), the CME blow that Earth's magnetic field receives will be a glancing one. They currently estimate it should pass Earth on July 31st around 15:00 UTC (11:00 AM EDT), give or take 7 hours either way of that estimate.

This incoming CME will also pass Mercury and have a greater affect there than at Earth. This is for two reasons. First, Mercury is closer to the sun and the CME cloud will not have dispersed as widely as it will when it passes Earth. Second, Mercury's magnetic field is only about 10 percent that of Earth's, and so Mercury is not as well protected.

The estimate of the CME arrival will likely change as the time draws closer. Stay tuned...

To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: www.swpc.noaa.gov .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

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July 29th, AR 1532 M1-Class Flare


The above image was taken July 29th at 06:22 UTC by the Atmospheric Imaging Assembly (AIA), at 94 Angstroms, aboard the Solar Dynamics Observatory (SDO). The M1-class solar flare may be seen at the lower left. Image Credit: SDO/AIA

The sun's Active Region 1532 (AR 1532) continues to rumble a bit. On July 29th at about 06:22 UTC (2:22 AM EDT), AR 1532 produced a M1-class solar flare. We see an extreme-ultraviolet view through the courtesy of NASA's Solar Dynamics Observatory (SDO). The M1-class flare may seem a little anticlimactic after the M6-class flare the previous day, be we won't complain. Since that time, the sun has produced a few C-class flares, but nothing more. We will continue to watch this feisty Active Region as it continues to turn toward Earth.

Back at home, the high-speed solar winds coming through that coronal hole are continuing to buffet Earth. NOAA forecasters estimate a 45 percent chance of polar geomagnetic storms over July 29th and 30th, so observers in the high latitudes should be on the lookout for possible aurora activity. The storm chances should then subside, as the coronal hole is expected to turn away from Earth by July 31st.

AR 1532 may be taking a breather, but we will keep an eye on the region with great interest. Stay tuned...

To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: www.swpc.noaa.gov .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

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NuSTAR Passes Post-Launch Assessment


The above image is an artist's concept of NASA's NuSTAR spacecraft in Earth orbit, with the 10-meter (30-foot) mast deployed. The optics modules are on the far right and the detectors are positioned at the focal plane on the far left. Image Credit: NASA/JPL-Caltech

On July 27th we finally received a much anticipated update on NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission. It seems this week, the spacecraft passed its Post-Launch Assessment Review at the Jet Propulsion Laboratory (JPL) in Pasadena, California. This achievement clears the way for the mission to enter into its science operations phase in August. NuSTAR is currently in the final stages of "Phase C/D," or the design and development phase, which included building and testing the flight hardware, launch and early operations (e.g., spacecraft checkout, mast deployment, instrument commissioning and calibrations). In August, NuSTAR will enter "Phase E," or the operations phase, meaning that it will primarily gather science data.

Since obtaining its first-light images of the galactic black hole Cygnus X-1 on June 28th, NuSTAR has been observing bright X-ray sources across the sky as part of the instrument commissioning. Last week, the mission participated in a major international cross-calibration campaign where NuSTAR and NASA's Chandra and Swift telescopes, together with INTEGRAL, Suzaku, and XMM-Newton, observed the quasar 3C 273 in concert. Quasar 3C 273, an extremely bright high-energy source at a distance of 2.4 billion light years, is the first quasar ever to be identified and is the optically brightest quasar in the sky. The coordinated observations of this bright, variable source will allow X-ray satellites to accurately measure their relative sensitivities and to conduct science investigations with joint data sets.

One example of a joint science observation took place between July 21st and 24th. NuSTAR observed the supermassive black hole that resides at the center of our own Milky Way galaxy as part of a large, multi-wavelength campaign. This supermassive black hole, our closest example, is known as Sagittarius A* (pronounced "Sagittarius A-star"). The descriptor of supermassive is accurate, since Sagittarius A* is approximately 4 million times the mass of our sun. NuSTAR obtained high-energy X-ray data on Sagittarius A*, complementing coordinated infrared images obtained with the Keck telescopes, low-energy X-ray data obtained with Chandra, and very high-energy gamma-ray data obtained with the High-Energy Stereoscopic System (HESS). These data will monitor the flickering of Sagittarius A* as it grows by accreting matter, thereby teaching astronomers about the extreme environments around black holes and the physics of black hole growth.Very soon, the hunt will be on for hidden black holes, in our galaxy and beyond.


And now, the mission particulars...

NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA's Jet Propulsion Laboratory, also in Pasadena, for NASA's Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corporation, Dulles, Virginia. Its instrument was built by a consortium including Caltech; JPL; the University of California, Berkeley (UC Berkley); Columbia University, New York; NASA's Goddard Space Flight Center, Greenbelt, Maryland; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, California; and ATK Aerospace Systems, Goleta, California. NuSTAR will be operated by UC Berkeley, with the Italian Space Agency providing its equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University, Rohnert Park, California. NASA's Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA. For more information on the NuSTAR mission, visit www.nasa.gov/nustar and www.nustar.caltech.edu/ .

To learn more about the High Energy Focusing Telescope (HEFT), visit www.srl.Caltech.edu/HEFT .

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Sunday, July 29, 2012

Southern Delta Aquarid Fireballs of July 28th

The above image is an overlapping of multiple frames of a July 28th fireball. Its passing was captured by camera "Huntsville (01A)" of NASA's All Fireball Network, taken July 28th at 05:54 UTC. Image Credit: NASA

Well, if anyone had doubts about the parentage of the Southern Delta Aquarid meteor shower, they may have just been swept away. It looks like 96P/Machholz has paternity (or is it maternity?).

Over the evening of July 27th-28th, NASA's All Fireball Network (fireballs.ndc.nasa.gov) detected 17 fireballs over North America with the brightness of Venus (currently magnitude -4.6). And what's more, at least half of these meteors had projected orbits corresponding with that of Comet 96P/Machholz, discovered by amateur astronomer Donald Machholz in 1986.

The comet is currently in the neighborhood. It reached perihelion on July 14 and it will have its closest approach to Earth on August 1st (0.894 AU). At that time the comet should be at celestial coordinates (J2000) R.A. 11h 21m 08.8s Dec. +26d 10m 25s with a brightness of magnitude 10.31.

Comet 96P/Machholz is currently in the constellation Leo, the Lion. For this weekend, the coordinates are: July 28th, R.A. 10h 33m 05.5s Dec. +29d 14m 15s (mag 9.33); July 29th, R.A. 10h 45m 33.2s Dec. +28d 35m 37s (mag 9.59). The best chance of observing the comet is through a medium-sized telescope, where under high magnification it looks like a tiny, fuzzy ball.

To learn more about meteors, comets, and asteroids, check out these URLs.

NASA's All Fireball Network (fireballs.ndc.nasa.gov), part of NASA's Meteoroid Environment Office, www.nasa.gov/offices/meo .

Asteroids, Comets, Meteorites (a NASA Asteroid Watch article): www.jpl.nasa.gov/asteroidwatch/asteroids-comets.cfm

NASA's Near-Earth Object (NEO) Program coordinates NASA-sponsored efforts to detect, track and characterize potentially hazardous asteroids and comets that could approach the Earth. To learn more, visit the home page of NASA's Near-Earth Object Program: neo.jpl.nasa.gov .

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July 28th, AR 1532 M6-Class Flare


The above image was taken July 28th at 21:02 UTC by the Atmospheric Imaging Assembly (AIA), at 94 Angstroms, aboard the Solar Dynamics Observatory (SDO). The M6-class solar flare may be seen at the lower left. Image Credit: SDO/AIA

Well lookie there! The sun's Active Region 1532 (AR 1532) is at it, again. And just a day after its M2.7-class flare. On July 28th at about 21:02 UTC (5:02 PM EDT), AR 1532 erupted with a M6-class solar flare. We see above the view in extreme ultraviolet, from NASA's Solar Dynamics Observatory (SDO).

According to the peak flux scale, this flare was considered moderately strong. And as of yet, forecasters cannot confirm whether the flare produced a coronal mass ejection (CME). But even so, Earth would receive a glancing blow, but no more. That might change as that region continues to turn toward Earth.

Since we are talking about flares and CMEs and their potential implications, let's take this opportunity to review our primers on solar flares and CMEs.

Solar Flare Primer

A solar flare is an explosion on the sun that occurs when the energy stored in twisted magnetic fields (usually above sunspots) is suddenly released. Flares produce a burst of radiation across the electromagnetic spectrum, from radio waves to X-rays and gamma-rays.

Solar flares are classified, from lowest to highest, as A, B, C, M and X according to the peak flux (in watts per square meter, W/m^2) of 100 to 800 picometer X-rays near Earth, as measured on the GOES spacecraft. The five categories break down as follows.

A-class: Peak flux of less than 10^-7 Watts/square meter. A-class flares produce no noticeable consequences on Earth.

B-class: Peak flux ranges from 10^-7 to 10^-6 Watts/square meter. B-class flares produce no noticeable consequences on Earth.

C-class: Peak flux ranges from 10^-6 to 10^-5 Watts/square meter. C-class flares produce few noticeable consequences
on Earth.

M-class: Peak flux ranges from 10^-5 to 10^-4 Watts/square meter. M-class flares  can cause brief radio blackouts that affect Earth's polar regions. Minor radiation storms sometimes follow an M-class flare.

X-class: Peak flux is greater than 10^-4 Watts/square meter. X-class flare are major events that can trigger planet-wide radio blackouts and long-lasting radiation storms.

Within each category are nine subdivisions of strength. For example, C1 to C9, M1 to M9, and so on. On July 14, 2000, the sun produced a X6 flare which triggered a major radiation storm around Earth and was nicknamed the Bastille Day event.

Coronal Mass Ejection Primer

A coronal mass ejection (CME) is a massive burst of solar wind, plasma, and magnetic fields rising above the solar corona or being released into space.

CMEs are often associated with other forms of solar activity, most notably solar flares, but a causal relationship between the two has not been established. Most CMEs originate from active regions on Sun's surface, such as groupings of sunspots associated with frequent flares. Near a solar maximum — the period of greatest activity in a solar cycle — the sun produces about three CMEs every day, whereas near a solar minimum — the period of least activity in a solar cycle — there is about one CME every five days.

Wrapping Up

With what have seen so far from AR 1532, things are sure to get interesting in the coming days. Stay tuned...

To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: www.swpc.noaa.gov .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

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Saturday, July 28, 2012

AR 1532's M2.7 Flare of July 27th


The above image was taken July 27th at 17:26 UTC by the Atmospheric Imaging Assembly (AIA), at 94 Angstroms, aboard the Solar Dynamics Observatory (SDO). The M2.7-class solar flare may be seen at the lower left. Image Credit: SDO/AIA

Alrighty then. It seems that the sun's recently-arrived Active Region 1532 (AR 1532) may have been inspired by the antics of the now-departed AR 1520. On July 27th at about 17:26 UTC (9:26 PM EDT), AR 1532 let out a M2.7-class solar flare. NASA's Solar Dynamics Observatory (SDO) captured the flare most dramatically in its extreme ultraviolet images.

While the solar flare was respectable, it did not build and subside gradually, and so did not have an opportunity to produce a substantial coronal mass ejection (CME). But even if it had, Earth is not currently in the line of fire from AR 1532. But give it time. As that region of the sun rotates to face Earth in the coming days, anything is possible.


Meanwhile, back at Earth, the geomagnetic field is expected to be relatively quiet on July 28th as the onset of the sun's coronal hole turns more directly toward Earth. High-speed stream effects are forecasted. The affects are expected to increase on July 29th and then wane as the coronal hole turns past Earth on July 30th. Stay tuned...


To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: www.swpc.noaa.gov .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

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Friday, July 27, 2012

2012 Southern Delta Aquarids

The above image is a chart of the constellation Aquarius, presented by the International Astronomical Union (IAU). The location of the radiant point of the Southern Delta Aquarid meteor shower is indicated by the radiating red lines. Image Credit: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)

This Saturday and Sunday, July 28th and 29th, mark the peak of the Southern Delta Aquarid meteor shower. The peak of this shower can produce about 20 meteors per hour, but a smaller rate can also be seen from July 18th through August 18th. The radiant point for this shower is in the constellation Aquarius, the Water Bearer.

This shower is not as famous as other annual meteor showers, but the Southern Delta Aquarids are reliable. This year, Observers will have to set their alarm clock to get the most out of this celestial event.

The moon will set after midnight local time and the darkest skies are the best time to catch the shooting stars. So, from about 1:00 AM local time until dawn will be the best time to watch. And a dark viewing location, away from the light pollution of cities, is also a must.

Because of the location in the sky of the constellation Aquarius, the Southern Delta Aquarids favor observers in southern latitudes in the northern hemisphere and all of the southern hemisphere.

Meteors occur when Earth passes through the dust trail left by comet. And the identity of the parent comet for this shower has been a mystery. But some experts suggest one possibility is Comet 96P/Machholz, discovered by amateur astronomer Donald Machholz in 1986. This "dirty snowball" is currently in the neighborhood. It reached perihelion on July 14 and it will have its closest approach to Earth on August 1st (0.894 AU). At that time the comet should be at celestial coordinates (J2000) R.A. 11h 21m 08.8s Dec. +26d 10m 25s with a brightness of magnitude 10.31.

Comet 96P/Machholz is currently in the constellation Leo, the Lion. For this weekend, the coordinates are: July 28th, R.A. 10h 33m 05.5s Dec. +29d 14m 15s (mag 9.33); July 29th, R.A. 10h 45m 33.2s Dec. +28d 35m 37s (mag 9.59). The best chance of observing the comet is through a medium-sized telescope, where under high magnification it looks like a tiny, fuzzy ball.

Some have suggested that, if 96P/Machholz is indeed the parent, wouldn't it be a one-in-a-lifetime experience to see both a meteor shower and its parent simultaneously! But depending where you are, don't let your inability to see one prevent you from at least trying to see the other. After all, in backyard astronomy, you make the most of what you have.

To learn more about meteors, comets, and asteroids, check out these URLs.

Asteroids, Comets, Meteorites (a NASA Asteroid Watch article): www.jpl.nasa.gov/asteroidwatch/asteroids-comets.cfm

NASA's Near-Earth Object (NEO) Program coordinates NASA-sponsored efforts to detect, track and characterize potentially hazardous asteroids and comets that could approach the Earth. To learn more, visit the home page of NASA's Near-Earth Object Program: neo.jpl.nasa.gov .

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It Belongs in a Museum!

The above image is an example of a large fireball breaking up in Earth's atmosphere. This type of exploding meteor is called a bolide. Image Credit: NASA/JPL-Caltech

"It belongs in a Museum!" That particular phrase was a favorite of a certain fictional, fedora-wearing, whip-wielding, pistol-packing archaeologist of which I'm rather fond.

But in this case, the phrase was uttered, until quite recently, by Knut Jørgen Røed Ødegaard, Norwegian astronomer, manager of the Harestua Solar Observatory and a popular interviewee for astronomical stories. The details are in an article published July 26th in The Foreigner, an Norwegian news service (theforeigner.no).CLICK HERE to read the July 26th article.

It all started back on the evening of Thursday, March 1st, when a large exploding fireball, also called a bolide, was seen and heard over southern Norway and parts of Sweden (CLICK HERE to read the March 2nd article in The Foreigner). The fall left chunks of meteorite scattered over the same region. About 800 had been reported as of this writing. One made a hole in the roof of a property in Oslo. And another fragmented in several pieces after hitting the frozen ground.

One individual discovered a large meteorite fragment, weighing 4.6 kilograms (just over 10 pounds), in the capital’s Grefsen district in the spring. The find is believed to be the largest in Norway in at least 100 years. But other than the general information, nothing more was heard about the large meteorite or the individual who reported it.

Always a champion for astronomy, Mr. Ødegaard appeared on the local NRK evening news, reminding the public of the fall, explaining the scientific importance of the rock, and asking for any information as to its whereabouts. Even representatives of the Oslo Natural History Museum got into the spirit of things, promising a finder's fee to anyone who could help locate the large meteorite. But nothing more was learned...until this week.

On Thursday, July 26th, museum personnel admitted they received an email from Mr. Ødegaard, dated July 4th, informing them the meteorite was in his possession after he bought it from the discoverer in Grefsen. The museum representatives were relieved of the news, but also puzzled and disappointed that Mr. Ødegaard had not, as of yet, followed his own advice and offered to present the big rock over to the museum himself.

Perhaps Mr. Ødegaard has plans that involve the Harestua Solar Observatory where he works, or perhaps he is quietly assembling a scientific team to study the meteorite, or perhaps he just plans to put up a sign and sell ticks. Nothing more is known at this item.

Of course, if I was to reflect on the adventures of the aforementioned fictional archaeologist, this would not be the first time that a prize of great importance was found and then quietly hidden away. It seems we will just have to wait and see what happens next...

If you wish to learn more about meteorites, meteors and Near-Earth Objects in general, I can think of no better way to start than by visiting the online home of NASA's Near-Earth Object (NEO) Observation Program. Back in 1998, NASA established the program to coordinate the agency's efforts to detect, track and characterize Earth-approaching NEOs and comets larger than 1 kilometer in size. The program now also searches for NEOs as small as object 2011 AG5. NASA supports NEO observation, tracking and analysis activities worldwide. Activities are coordinated through the NEO Program Office at the Jet Propulsion Office (JPL) in Pasadena, California. To learn more, visit: neo.jpl.nasa.gov .

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Earliest Spiral Galaxy Found So Far...

Above is a composite of two images. The left image is an HST/Keck false color composite of galaxy BX442. The right image is an artist's rendering of BX442 and its companion dwarf galaxy. Image Credit: (left) David Law/Dunlap Institute for Astronomy & Astrophysics; (right) Dunlap Institute for Astronomy & Astrophysics/Joe Bergeron


Astronomers have seen their first spiral galaxy in the early universe, billions of years before other spiral galaxies formed. Researchers said they discovered it while using the Hubble Space Telescope to take pictures of about 300 very distant galaxies in the early universe and to study their properties. This distant spiral galaxy is being observed as it existed roughly three billion years after the Big Bang, and light from this part of the universe has been traveling to Earth for about 10.7 billion years. The findings were reported July 19th in the journal Nature. CLICK HERE to view the Nature article online.


The lead author of the study is David Law, Dunlap Institute postdoctoral fellow at the University of Toronto's Dunlap Institute for Astronomy & Astrophysics, and former Hubble postdoctoral fellow at UCLA. One co-author of the study is Alice Shapley, a UCLA associate professor of physics and astronomy.


Galaxies in today’s universe divide into various types, including spiral galaxies like our own Milky Way, which are rotating disks of stars and gas in which new stars form, and elliptical galaxies, which include older, redder stars moving in random directions. The mix of galaxy structures in the early universe is quite different, with a much greater diversity and larger fraction of irregular galaxies. In fact, the researchers were astounded the galaxy existed at all. The current thinking would not expect large, well-formed spiral galaxies to be present in such an early time in the universe.


The found galaxy was given the designation BX442 and is quite large compared with other galaxies from this early time. If the galaxies the researchers had analyzed, only about 30 are as massive as BX442.


To gain deeper insight into their unique image of BX442, Law and Shapley went to the W.M. Keck Observatory atop Hawaii’s dormant Mauna Kea volcano and used a unique state-of-the-science instrument called the OSIRIS spectrograph, which was built by James Larkin, a UCLA professor of physics and astronomy. They studied spectra from some 3,600 locations in and around BX442, which provided valuable information that enabled them to determine that it actually is a rotating spiral galaxy — and not, for example, two galaxies that happened to line up in the image. And what's more, there is evidence of an enormous black hole at the center of the galaxy and that the black hole might play a role in the galaxy's development.


Why such a resemblance to the common spiral galaxies today?


The researchers think the answer may have to do with a companion dwarf galaxy, which the OSIRIS spectrograph reveals as a blob in the upper left portion of the image, and the gravitational interaction between them. Support for this idea is provided by a numerical simulation conducted by Charlotte Christensen, a postdoctoral scholar at the University of Arizona and another co-author of study. And the thinking is that the small neighboring galaxy will likely merge into BX442.


The researchers expect that in the early universe, galaxies were colliding and merging much more frequently than they do in the current epoch. Much gas from the intergalactic medium was feeding the stars that were forming much more rapidly that they are today. And black holes grew at a faster rate as well.


The researchers will continue to study BX442 and they expect to learn the types of stars and the mixtures of gas that are present in the various parts of the galaxy.


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Be "There" for NASA's MSL/Curiosity Landing!

The above image is the banner graphic for NASA's Mars Science Laboratory mission participation page. Image Credit: NASA/JPL-Caltech

The entry and landing of the NASA's Mars Science Laboratory (MSL) / Curiosity mission is scheduled for August 5th at 10:31 PM PDT (1:31 AM EDT and 05:31 UTC August 6th). Can't make it to one of the planned events that coincide? No problem! Be "there" online.

On August 5th, beginning 11:30 PM EDT / 8:30 PM PDT, NASA will broadcast the landing coverage online. To join in, go to this URL, mars.jpl.nasa.gov/msl/participate .
If you're not sure whether an event is happening nearby, click the "Find Live Events in Your Town" link to, well, find live events in your town. And if you can't find an event, create your own! After all, this is a special occasion. I mean, it's not every day that a huge Mars rover streaks through the Martian atmosphere, slows itself by supersonic parachute and jetpack, and then lowers itself to the surface by a sky crane. I'm just sayin'...

Remember that URL, mars.jpl.nasa.gov/msl/participate , and you to will be able to tell everyone that you were "there!"

The Mars Science Laboratory / Curiosity rover mission is managed for NASA’s Science Mission Directorate, Washington, D.C., by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena (Caltech)More information about Curiosity is online at www.nasa.gov/msl and mars.jpl.nasa.gov/msl . You can follow the mission on Facebook at: www.facebook.com/marscuriosity and on Twitter at: www.twitter.com/marscuriosity .

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Thursday, July 26, 2012

Counting Sunspots for July 26th

Above is an SDO/HMI Continuum image of the sun, taken July 26, 2012 at 12:00 UTC by the Solar Dynamics Observatory. Image Credit: NASA/SDO/HMI

Since our sun is relatively quiet for the moment, let's take the opportunity to review the most noticeable active regions (sunspots) that are currently facing Earth. Beginning from the top and going roughly counter clockwise, we can make out AR 15027, AR 1528, AR 1529, AR 1530 (on the eastern limb), and AR 1525 (near the western limb). None of these regions currently poses a threat for strong solar flares.

As of July 25th, our sunspot count for the current 11-year solar cycle is 66. The current solar cycle, Cycle 24, began January 2008.

Even though we cannot see it in the visible spectrum, there is a coronal hole over the eastern-central portion of the sun's disc that is facing Earth. A solar wind stream from this area should soon rotate to face Earth and cause some geophysical activity over July 28th to 30th. No details yet on what we may expect. Stay tuned...

To monitor solar flare activity minute by minute, visit the "Today's Space Weather" page of NOAA's Space Weather Prediction Center, URL: www.swpc.noaa.gov .

To learn more about the sun and to stay current on solar activity, visit the mission home pages of the Solar Dynamics Observatory (SDO), sdo.gsfc.nasa.gov and the Solar and Heliospheric Observatory (SOHO), sohowww.nascom.nasa.gov .

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NuSTAR: Origins

 
The above composite shows images of the Crab Nebula in various energy bands, including a hard X-ray image from the HEFT data taken during its 2005 observation run. The field of view for each image is the same size, 6 arcseconds. Image Credit: CM Hubert Chen, Fiona A. Harrison, Principal Investigator, Caltech Charles J. Hailey, Columbia Principal, Columbia, Finn E. Christensen, DSRI Principal, DSRI, William W. Craig, Optics Scientist, LLNL, Stephen M. Schindler, Project Manager, Caltech

We now continue our review of NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission, which launched June 13th. In this outing we will review NuSTAR's road from proposal to reality. And the road was indeed long and winding...

The Proposal

In February 2003, NASA formally requested new mission proposals for their Explorer mission program, described as an Explorer Program Announcement of Opportunity. The chosen proposals would fly as the tenth and eleventh missions of the Small Explorer (SMEX) program.  In response, NASA received 36 proposals. One of these was for an Earth-orbiting X-ray telescope to carry out a census of black holes with 1,000 times more sensitivity than previous experiments which have flown. The mission would be led by Fiona Anne Harrison of the California Institute of Technology, Pasadena, at a total mission cost to NASA of $132 million. The mission would be called the Nuclear Spectroscopic Telescope Array — NuSTAR.

The Studies

In November 2003, NuSTAR was one of five proposals selected by NASA for a five-month implementation feasibility study. Following the studies, NASA would select two of the five for future missions.

In January 2005, NASA announced its selection of the Interstellar Boundary Explorer (IBEX) to be the next SMEX mission. In addition, NASA announced that NuSTAR was also selected for mission development, pending a one-year feasibility study.

As part of the feasibility study, the NuSTAR proposal team had to prove that their instrumentation was ready for space. To do that, they planned a high-altitude balloon flight over the deserts of New Mexico. The balloon phase of the project was given the name High-Energy Focusing Telescope (HEFT).

The new technology would be superior to that employed by existing X-ray satellites for certain observations because high-energy, or hard, X rays, tend to penetrate the gas and dust of galaxies much better than the soft X-rays observed by NuSTAR's forerunners. Thus, NuSTAR would get the first focused hard X-ray images for three basic science goals:

1. The taking of a census of black holes at all scales. NuSTAR would not only count them, but would also measure the "accretion rate" at which material has fallen into them over time, and the rate supermassive black holes have grown.

2. The detecting and measuring of radioactive stuff in recently exploded stars. These remnants of supernovae would provide a better idea of how elements are formed in supernova explosions and then mixed in the interstellar medium, which is the space between stars. NuSTAR would be especially good at observing the decay of titanium to calcium, which tends to be produced in the region of a supernova where material either is ejected forever from the explosion or falls back inward to form a compact remnant of some sort. NuSTAR would thus be an especially good probe of this region, and the data returned will contribute directly to NASA's "Cycles of Matter and Energy" program.

3. The observing and imaging of the highly energetic jets that stream out of certain black holes at nearly the speed of light. Coupled with observations from the Gamma-Ray Large-Area Space Telescope (GLAST), NuSTAR would provide data to help scientists explain this still-enigmatic but powerful phenomenon.

The technical difficulties of obtaining hard X-ray images was overcome with groundbreaking work in various Caltech labs, including that of famed inventor Carver Mead, who is the Moore Professor of Engineering and Applied Science, Emeritus, at Caltech. Both HEFT and NuSTAR would rely on an array of co-aligned conical mirrors that would focus X-rays from about 20 to 100 kilo-electron-volts on a pixel detector made of cadmium zinc telluride. The sensor is segmented into squares of about half a millimeter each and these would take thousands of individual readings of X-ray photons and turn them into electronic signals.

In addition to Caltech, the other participating organizations and universities were the Jet Propulsion Laboratory (managed by Caltech for NASA), Columbia University, the Stanford Linear Accelerator (SLAC), the Lawrence Livermore National Laboratory, Sonoma State University, the University of California at Santa Cruz, and the Danish Space Research Institute. NuSTAR's mast would be built by ABLE Engineering and the spacecraft would be built by General Dynamics Spectrum Astro.

JPL would handle project management, the metrology system, and the extensible mast, and would be involved in the mission's science. The mast would be based on a previous JPL mission called the Shuttle Radar Topography Mission.

Up, Up and Away!

In May 2005, the balloon-borne HEFT was first launched from Fort Sumner. The instrument carried one of the first focusing telescopes for the hard X-ray band (20–70 keV). It made use of tungsten-silicon multilayer coatings to extend the reflectivity of nested grazing-incidence mirrors beyond 10 keV. HEFT had an angular resolution of 1.5 arcminutes in half-power diameter, and an energy resolution of 1.0 keV full width at half maximum at 60 keV. The maiden flight of HEFT lasted 25 hours. The instrument performed within specification, and observed Cyg X-1, the Crab Nebula.

The flights of HEFT and the data it collected proved to NASA that NuSTAR would perform as advertised. Following the completion of the study, NASA green-lighted the NuSTAR program with an estimated mission launch in 2008.

To be continued.


And now, the mission particulars...


NuSTAR is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA's Jet Propulsion Laboratory, also in Pasadena, for NASA's Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corporation, Dulles, Virginia. Its instrument was built by a consortium including Caltech; JPL; the University of California, Berkeley (UC Berkley); Columbia University, New York; NASA's Goddard Space Flight Center, Greenbelt, Maryland; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, California; and ATK Aerospace Systems, Goleta, California. NuSTAR will be operated by UC Berkeley, with the Italian Space Agency providing its equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University, Rohnert Park, California. NASA's Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA. For more information on the NuSTAR mission, visit 
www.nasa.gov/nustar and http://www.nustar.caltech.edu/ .


To learn more about the High Energy Focusing Telescope (HEFT), visit www.srl.Caltech.edu/HEFT .

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MSL/Curiosity: A Primer

The above image is an artist's concept of NASA's Mars Science Laboratory Curiosity rover, rolling across the Martian landscape. Image Credit: NASA/JPL-Caltech

NASA's Mars Science Laboratory / Curiosity rover is scheduled to land on Mars the evening of August 5th, PDT (early August 6th, EDT and Universal Time). If you are not up to speed on the workings and the goals of the mission, there is no better time to start! Here is a rundown...


Mars Science Laboratory

NASA’s Mars Science Laboratory mission is preparing to set down a large, mobile laboratory — the rover Curiosity — using precision landing technology that makes many of Mars’ most intriguing regions viable destinations for the first time. During the 23 months after landing, Curiosity will analyze dozens of samples drilled from rocks or scooped from the ground as it explores with greater range than any previous Mars rover.

Curiosity will carry the most advanced payload of scientific gear ever used on Mars’ surface, a payload more than 10 times as massive as those of earlier Mars rovers. Its assignment: Investigate whether conditions have been favorable for microbial life and for preserving clues in the rocks about possible past life.

Mission Overview

The spacecraft has been designed to steer itself during descent through Mars’ atmosphere with a series of S-curve maneuvers similar to those used by astronauts piloting NASA space shuttles. During the three minutes before touchdown, the spacecraft slows its descent with a parachute, then uses retro rockets mounted around the rim of an upper stage. In the final seconds, the upper stage acts as a sky crane, lowering the upright rover on a tether to the surface.

Curiosity is about twice as long (about 3 meters or 10 feet) and five times as heavy as NASA’s twin Mars Exploration Rovers, Spirit and Opportunity, launched in 2003. It inherited many design elements from them, including six-wheel drive, a rocker-bogie suspension system and cameras mounted on a mast to help the mission’s team on Earth select exploration targets and driving routes. Unlike earlier rovers, Curiosity carries equipment to gather samples of rocks and soil, process them and distribute them to onboard test chambers inside analytical instruments.

NASA’s Jet Propulsion Laboratory, Pasadena, California, builder of the Mars Science Laboratory, has engineered Curiosity to roll over obstacles up to 65 centimeters (25 inches) high and to travel up to about 200 meters (660 feet) per day on Martian terrain.

The rover’s electrical power will be supplied by a U.S. Department of Energy radioisotope power generator. The multimission radioisotope thermoelectric generator produces electricity from the heat of plutonium-238’s radioactive decay. This long-lived power supply gives the mission an operating lifespan on Mars’ surface of a full Mars year (687 Earth days) or more. At launch, the generator will provide about 110 watts of electrical power to operate the rover’s instruments, robotic arm, wheels, computers and radio. Warm fluids heated by the generator’s excess heat are plumbed throughout the rover to keep electronics and other systems at acceptable operating temperatures.

The mission has been designed to use radio relays via Mars orbiters as the principal means of communication between Curiosity and the Deep Space Network of antennas on Earth.

The overarching science goal of the mission is to assess whether the landing area has ever had or still has environmental conditions favorable to microbial life, both its habitability and its preservation.

More than 100 scientists participating in a series of open workshops since 2006 compared merits of more than 30 Martian locations as potential landing sites for the rover. Evaluations of scientific appeal and safety factors led NASA to select four finalist candidate sites in 2008, with the final selection made in 2011. All four had exposures of minerals formed under wet conditions.

Selection of a landing site of prime scientific interest has benefited from examining candidate sites with NASA’s Mars Reconnaissance Orbiter since 2006, from earlier orbiters’ observations, and from a capability of landing within a target area only about 20 kilometers (12 miles) long. That precision, about a five-fold improvement on earlier Mars landings, makes feasible sites that would otherwise be excluded for encompassing nearby unsuitable terrain. For example, the mission could go to the floor of a crater whose steep walls would make a less precise landing too risky.

The site chosen was Gale Crater, located near the northwestern part of the Aeolis quadrangle at 5.4°S 137.8°E. The crater is 154 km (96 mi) in diameter and thought to be about 3.5 to 3.8 billion years old. The crater was named after Walter Frederick Gale, an amateur astronomer from Sydney, New South Wales, Australia, who observed Mars in the late 19th century and erroneously described the presence of canals. Aeolis Mons is a mountain in the center of Gale Crater and rises 5.5 km (18,000 ft) high. Aeolis Palus is the plain between the northern wall of Gale Crater and the northern foothills of Aeolis Mons.

Aeolis Mons or Mount Sharp?

In March 2012 NASA published "Mount Sharp" as a term for the previously unnamed central peak of Gale Crater. In May 2012 the International Astronomical Union (IAU) officially named the peak "Aeolis Mons," and named a large crater, 152.08 km (94.50 mi) in diameter, located about 260 km (160 mi) west of Gale Crater, "Robert Sharp Crater."

Advancing the technologies for precision landing of a heavy payload will yield research benefits beyond the returns from Mars Science Laboratory itself. Those same capabilities would be important for later missions both to pick up rocks on Mars and bring them back to Earth, and conduct extensive surface exploration for Martian life.

Science Payload

In April 2004, NASA solicited proposals for specific instruments and investigations to be carried by Mars Science Laboratory. The agency selected eight of the proposals later that year and also reached agreements with Russia and Spain for carrying instruments those nations will provide.

A suite of instruments named Sample Analysis at Mars will analyze samples of material collected and delivered by the rover’s arm. It includes a gas chromatograph, a mass spectrometer, and a tunable laser spectrometer with combined capabilities to identify a wide range of organic (carbon-containing) compounds and determine the ratios of different isotopes of key elements. Isotope ratios are clues to understanding the history of Mars’ atmosphere and water. The principal investigator is Paul Mahaffy of NASA’s Goddard Space Flight Center, Greenbelt, Maryland.

An X-ray diffraction and fluorescence instrument called CheMin will also examine samples gathered by the robotic arm. It is designed to identify and quantify the minerals in rocks and soils, and to measure bulk composition. The principal investigator is David Blake of NASA’s Ames Research Center, Moffett Field, California.

Mounted on the arm, the Mars Hand Lens Imager will take extreme close-up pictures of rocks, soil and, if present, ice, revealing details smaller than the width of a human hair. It will also be able to focus on hard-to-reach objects more than an arm’s length away. The principal investigator is Kenneth Edgett of Malin Space Science Systems, San Diego.

Also on the arm, the Alpha Particle X-ray Spectrometer for Mars Science Laboratory will determine the relative abundances of different elements in rocks and soils. Dr. Ralf Gellert of the University of Guelph, Ontario, Canada, is principal investigator for this instrument, which will be provided by the Canadian Space Agency.

The Mars Science Laboratory Mast Camera, mounted at about human-eye height, will image the rover’s surroundings in high-resolution stereo and color, with the capability to take and store high-definition video sequences. It will also be used for viewing materials collected or treated by the arm. The principal investigator is Michael Malin of Malin Space Science Systems.

An instrument named ChemCam will use laser pulses to vaporize thin layers of material from Martian rocks or soil targets up to 9 meters (30 feet) away. It will include both a spectrometer to identify the types of atoms excited by the beam, and a telescope to capture detailed images of the area illuminated by the beam. The laser and telescope sit on the rover’s mast and share with the Mast Camera the role of informing researchers’ choices about which objects in the area make the best targets for approaching to examine with other instruments. Roger Wiens of Los Alamos National Laboratory, Los Alamos, N.M., is the principal investigator.

The rover’s Radiation Assessment Detector will characterize the radiation environment at the surface of Mars. This information is necessary for planning human exploration of Mars and is relevant to assessing the planet’s ability to harbor life. The principal investigator is Donald Hassler of Southwest Research Institute, Boulder, Colorado.

In the two minutes before landing, the Mars Descent Imager will capture color, high-definition video of the landing region to provide geological context for the investigations on the ground and to aid precise determination of the landing site. Michael Malin is principal investigator.

Spain’s Ministry of Education and Science is providing the Rover Environmental Monitoring Station to measure atmospheric pressure, temperature, humidity, winds, plus ultraviolet radiation levels. The principal investigator is Javier Gómez-Elvira of the Center for Astrobiology, Madrid, an international partner of the NASA Astrobiology Institute. The team for this investigation includes the Finnish Meteorological Institute as a partner.

Russia’s Federal Space Agency is providing the Dynamic Albedo of Neutrons instrument to measure subsurface hydrogen up to one meter (three feet) below the surface. Detections of hydrogen may indicate the presence of water in the form of ice or bound in minerals. Igor Mitrofanov of the Space Research Institute, Moscow, is the principal investigator.

In addition to the science payload, equipment of the rover’s engineering infrastructure will contribute to scientific observations. Like the Mars Exploration Rovers, Curiosity will have a stereo navigation camera on its mast and lowslung, stereo hazard-avoidance cameras. Equipment called the Sample Acquisition/Sample Preparation and Handling System includes tools to remove dust from rock surfaces, scoop up soil, drill into rocks and collect powdered samples from rocks’ interiors, sort samples by particle size with sieves, and deliver samples to laboratory instruments.

The Mars Science Laboratory Entry, Descent and Landing Instrument Suite is a set of engineering sensors designed to measure atmospheric conditions and performance of the spacecraft during the arrival-day plunge through the atmosphere, to aid in design of future missions.

And now, the mission particulars...

The Mars Science Laboratory / Curiosity rover mission is managed for NASA’s Science Mission Directorate, Washington, D.C., by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena (Caltech)More information about Curiosity is online at www.nasa.gov/msl and mars.jpl.nasa.gov/msl . You can follow the mission on Facebook at: www.facebook.com/marscuriosity and on Twitter at: www.twitter.com/marscuriosity .

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Wednesday, July 25, 2012

Coming September 8th, Hasta La Vesta!

The above image marks the location of NASA's Dawn spacecraft as of July 26, 2010 at 04:00 UTC. Also marked is the orbital path Dawn will take as it departs Vesta and travels to dwarf planet Ceres. Image Credit: NASA/JPL-Caltech

NASA's Dawn mission team has had an amazing year exploring Vesta. But the mission extension concludes in late August, and includes capturing images of Vesta's elusive north polar region.

Once the Vesta phase of the mission ends, the Dawn team will say "hasta la vista, Vesta!" and start Dawn on its journey to dwarf planet Ceres. But before they cast their full focus on Ceres, they will take a moment to revel in the discoveries of Vesta. And the team is inviting us to join the party!

We are invited to celebrate with NASA and the Dawn mission team. We can connect with Dawn team members and fellow Dawn mission fans in real time. Dawn scientists and engineers will share mission stories and answer questions via Facebook and Twitter in a live, interactive video event.

How are we celebrating? With a real-time MissionCast called "Hasta La Vista, Vesta!" Mark your calendars for September 8th at 12:00 PM PDT (3:00 PM EDT). Dawn scientists and engineers will share mission stories and answer questions submitted via Facebook and Twitter in a live, interactive video event.

If you have any questions, connect with the Dawn team via email (dawnepo@gmail.com) or via Facebook (www.facebook.com/dawn.mission) or Twitter (twitter.com/NASA_Dawn).

And now, the mission particulars...

The Dawn mission to Vesta and Ceres is managed by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington D.C. UCLA is responsible for overall Dawn mission science. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. Orbital Sciences Corporation (OSC) in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. The Dawn framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The Framing Camera project is funded by the Max Planck Society, DLR, and NASA/JPL. The California Institute of Technology in Pasadena manages JPL for NASA.

To view the new Vesta images and for more information about Dawn, visit: www.nasa.gov/dawn and dawn.jpl.nasa.gov .

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