Friday, August 30, 2013

NuSTAR Delivers the Good Stuff!

NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, is giving the wider astronomical community a first look at its unique X-ray images of the cosmos. The first batch of data from the black-hole hunting telescope was first made available on August 29th via NASA's High Energy Astrophysics Science Archive Research Center, or HEASARC.

Sculptor Galaxy Shines with X-rays
Above is a composite image of the Sculptor galaxy, combining observations from NuSTAR and the European Southern Observatory in Chile. Image Credit: NASA/JPL-Caltech/JHU
 
The images, taken from July to August 2012, shortly after the spacecraft launched, comprise an assortment of extreme objects, including black holes near and far. The more distant black holes are some of the most luminous objects in the universe, radiating X-rays as they ferociously consume surrounding gas. One type of black hole in the new batch of data is a blazaran active, supermassive black holethat is pointing a jet toward Earth. Also in the mix are X-ray binariespairs of black holes in which one partner feeds off the otheras well as the remnants of supernovas.

The data set only contains complete observations. Data will be released at a later date for those targets still being observed. Astronomers can use the data to better understand the capabilities of NuSTAR and design their future observing proposals. The first opportunity will be this fall, for joint observations with XMM-Newton.

The European Space Agency's XMM-Newton X-ray telescope, like NASA's Chandra X-ray Observatory, complements NuSTAR. While XMM-Newton and Chandra see lower-energy X-ray light, NuSTAR is the first telescope capable of focusing high-energy X-ray light, allowing for more detailed images than were possible before.

Sizzling Remains of a Dead Star
Above is an image of supernova remnant Cassiopeia A, located 11,000 light-years away, was taken by NuSTAR. Blue indicates the highest energy X-ray light. Red and green show the lower end of NuSTAR's energy range, which overlaps the capabilities of NASA's high-resolution Chandra X-ray Observatory. Image Credit: NASA/JPL-Caltech/DSS
 
Astronomers can compare data sets from different missions using HEASARC, which gives them a broader understanding of an object of interest. NuSTAR's high-energy observations help scientists bridge a gap that existed previously in X-ray astronomy, and will lead to new revelations about the bizarre and energetic side of our universe.

Other NASA missions with data available via HEASARC include Chandra, Fermi, Swift, Cosmic Background Explorer (COBE), Wilkinson Microwave Anisotropy Probe (WMAP) and many more.

The HEASARC is a service of the Astrophysics Science Division at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the High Energy Astrophysics Division of the Smithsonian Astrophysics Observatory in Cambridge, Mass. HEASARC holdings include data obtained by NASA's high-energy astronomy missions observing in the extreme-ultraviolet, X-ray, and gamma-ray bands, as well as data from missions, balloons and ground-based facilities that have studied the relic cosmic microwave background. HEASARC is online at http://heasarc.gsfc.nasa.gov .

Above is an artist's concept of the fully-deployed NuSTAR in Earth orbit. The section the foreground and to the top, contains the two round "lenses" for the observatory. The light they receive is focused on the receiving points in the rear section, located 10 meters away. Image Credit: NASA/JPL-Caltech/JHU

Launched June 13, 2012 aboard an Orbital Sciences Pegasus XL rocket, NuSTAR is a Small Explorer mission led by Caltech and managed by NASA's Jet Propulsion Laboratory, Pasadena, California, 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; Columbia University, New York; NASA's Goddard Space Flight Center, Greenbelt, Md.; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, Calif.; ATK Aerospace Systems, Goleta, California, and with support from the Italian Space Agency (ASI) Science Data Center.

NuSTAR's mission operations center is at UC Berkeley, with ASI 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.

Click here to visit NASA's NuSTAR page.

Click here to visit Caltech's NuSTAR mission website.


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Thursday, August 29, 2013

Bruce Churchill Murray, 1931 - 2013

Bruce Churchill Murray, the Caltech professor of planetary science and geology who served as director of the Jet Propulsion Laboratory (JPL) from 1976 to 1982, died at his home in Oceanside, California on August 29 at the age of 81. Murray was JPL's director during the Viking landings on Mars and the early missions of Voyager 1 and 2 as the twin spacecraft flew by Jupiter and Saturn.

Murray and Carl Sagan
The above image shows Bruce C. Murray (left) and Carl Sagan (right) looking at a map of Mars. The photo was taken in 1976 in Murray's office while Sagan was living in Pasadena and working on the Viking mission. Image credit: NASA/JPL-Caltech

As JPL director, Murray faced a rapidly shrinking budget as NASA's priorities solidified around the space shuttle and its focus on taking astronauts and payloads to low Earth orbit. As the agency cut back its planetary program, he gained a substantial expansion of JPL's civil affairs program with a large solar energy research project funded by the Department of Energy.

Murray also waged political battles in Washington to save the planetary program — and JPL. In 1979, Murray joined with the late astronomer Carl Sagan and engineer Louis Friedman to found the Planetary Society, a membership-based nonprofit organization dedicated to exploring the solar system and expanding public advocacy for space exploration.

Murray salvaged for JPL the Galileo mission to Jupiter, but lost the American half of the two-satellite International Solar Polar Mission (eventually launched with JPL instruments as the European Space Agency's Ulysses by space shuttle Discovery) and a proposed U.S. mission to Halley's comet. Murray also brought the American portion of the joint Netherlands/United Kingdom/U.S. Infrared Astronomy Satellite to JPL, and Caltech gained the project's science data center.

In the midst of budget cuts in 1981, Murray struck a defiant note in an interview with Discover magazine. "We're sitting here watching the coffin being nailed shut, and what's inside is imagination and vision," he told the publication. "I wasn't appointed director to preside over the dissolution of the U.S. space exploration program ... I'm not going to be squeezed down to nothing."

During Murray's leadership, JPL launched Seasat, one of the earliest Earth-observing satellites; the Solar Mesosphere Explorer, an Earth-orbiting spacecraft that investigated the ozone in Earth's upper atmosphere; and Shuttle Imaging Radar-A, designed to fly aboard Space Shuttle Columbia as the first instrument that imaged Earth using radar pulses, rather than optical light, as illumination.

A strong advocate of planetary exploration, Murray disagreed with the focus of the Viking missions — the search for life on Mars — because he saw it as premature, thinking that without an adequate understanding of Martian surface chemistry, the biological instruments would not be able to provide unambiguous results.

After earning a Ph.D. in geology at MIT in 1955, Murray worked as a geologist for Standard Oil until 1958, then served two years in the U.S. Air Force. He came to Caltech in 1960, initially working in planetary astronomy, and soon became part of the imaging science team for JPL's first two missions to Mars, Mariners 3 and 4. He served a similar role on Mariners 6, 7 and 9, using their imagery to begin constructing a geologic history for Mars.

Murray published more than 130 scientific papers and authored or co-authored seven books. After he retired as director in late 1982 Murray returned to Caltech's Geological and Planetary Sciences Division, and was later named an emeritus professor at the campus.

Murray is survived by his wife, Suzanne Moss, five children and grandchildren.

Asteroid 4957 Brucemurray is named after him.



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Ceres Could Hold More Than We Thought

There is a new article on the Astrobiology Magazine that describes the dwarf planet Ceres as a "game changer" in that scientist may find more on that small body than they originally expected.

 
Above is the dwarf planet Ceres as seen by the Hubble Space Telescope. Image Credit: NASA, ESA, J. Parker (Southwest Research Institute), P. Thomas (Cornell University), L. McFadden (University of Maryland, College Park), and M. Mutchler and Z. Levay (STScI)

NASA's Dawn mission will arrive at Ceres in March of 2015. Discovered in 1801, Ceres was then thought to be a planet, but has since been reclassified (in 2006) as a dwarf planet. Ceres is the closest of its class to the orbit of Earth, orbiting in the asteroid belt between Mars and Jupiter. Ceres bears many similarities to Jupiter's moon Europa and Saturn's moon Enceladus, both considered to be potential sources for harboring life.

Ceres is the most massive body in the asteroid belt, and larger than some of the icy moons scientists consider ideal for hosting life. It is twice the size of Enceladus, which may hold liquid water beneath its surface.

Unlike other asteroids, the Texas-sized Ceres is round, suggesting that it almost certainly formed in the early solar system. If it formed later, there would have been less ice available, and so Ceres would not be as rounded in shape.

Ceres' shape, size and total mass reveal it to be a body of very low density. Scientists suggest it might even have had a liquid ocean at one point in its history. Once difference between Ceres and other icy solar system bodies is that it's closer to the Sun. Ceres is close enough to feel the Sun's warmth, allowing its ice to melt and reform.

Exploring the interior of this dwarf planet could provide insight into the early solar system, especially locations where water and other volatiles might have existed. For this reason, Ceres is thought to be the key to understanding the history of water in the middle solar system.

Click here to read the full article online at Astrobiology Magazine.

Click here to learn more about NASA's Dawn mission to Vesta and Ceres.


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Wednesday, August 28, 2013

Curiosity's Progress As Of August 27th

NASA's Mars rover Curiosity left the 'Glenelg' area on July 4, 2013, on a 'rapid transit route' to the entry point for the mission's next major destination, the lower layers of Mount Sharp.
Image Credit: NASA/JPL-Caltech

As we noted earlier today, NASA's Mars rover Curiosity left the "Glenelg" area on July 4, 2013, on a "rapid transit route" to the entry point for the mission's next major destination, the lower layers of Mount Sharp. As of August 27, 2013, Curiosity has driven about 0.86 mile (1.39 kilometers) since leaving Glenelg, with about 4.46 miles (7.18 kilometers) remaining to get to the entry point. The rover's drive on August 27, the 376th sol (Martian day) of the mission, was the first Curiosity drive using the rover's autonomous navigation capability to safely drive beyond the area that rover drivers on Earth could evaluate from images before the drive. The rover can analyze stereo images that it takes during the drive and choose the best path to continue driving.

The rapid transit route was plotted on the basis of images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Actual drives are based on images from Curiosity's own cameras, and the total driving distance to the entry point could differ from the length of the rapid transit route.

Curiosity's science team has identified some geological waypoints along the rapid transit route where driving may be suspended for a few sols to allow time for studying local features. The rover has about 0.31 mile (500 meters) left to go before reaching the first of these waypoints. For a broader-context image of the area, click here.

The above map shows Curiosity's location at the end of the Sol 376 drive, in the context of the mission's initial drive from the landing site at Bradbury Landing to Glenelg and the route of the current drive from Glenelg to the Mount Sharp entry point. Geological waypoints along the route are also indicated. The base map is from the orbiting HiRISE camera. North is toward the top. The dark ground south of the rapid transit route has dunes of dark, wind-blown material. The 4-kilometer scale bar on the map is about 2.5 miles long.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.

More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.

Click here to visit the NASA/JPL website for the Mars Curiosity mission.

Click here to visit the main NASA website for the Mars Curiosity mission.

Click here to visit the NASA Mars Exploration website for the Mars Curiosity mission.

Click here to follow the mission on Facebook.

Click here to follow the mission on Twitter.


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Curiosity Has Soloed!

NASA's Mars Curiosity has soloedthat is, the rover has used autonomous navigation for the first time. This capability lets the rover decide for itself how to drive safely on Mars.

View Ahead After Curiosity's Sol 376 Drive Using Autonomous Navigation
Above is a mosaic of images from the Navigation Camera (Navcam) on NASA's Mars rover Curiosity, showing the scene from the rover's position on the 376th Martian day, or sol, of the mission (Aug. 27, 2013). The images were taken right after Curiosity completed the first drive during which it used autonomous navigation on unknown ground. Credit: NASA/JPL-Caltech

This autonomous functionality will help the rover cover the remaining ground en route to Mount Sharp, where geological layers hold information about environmental changes on ancient Mars. The capability uses software that engineers adapted to this larger and more complex vehicle from a similar capability used by NASA's Mars Exploration Rover Opportunity, which is also currently active on Mars.

Using autonomous navigation, or autonav, Curiosity can analyze images it takes during a drive to calculate a safe driving path. This enables it to proceed safely even beyond the area that the human rover drivers on Earth can evaluate ahead of time.

On Tuesday, August 27, Curiosity successfully used autonomous navigation to drive onto ground that could not be confirmed safe before the start of the drive. This was a first for Curiosity. In a preparatory test last week, Curiosity plotted part of a drive for itself, but kept within an area that operators had identified in advance as safe.

"Curiosity takes several sets of stereo pairs of images, and the rover's computer processes that information to map any geometric hazard or rough terrain," said Mark Maimone, rover mobility engineer and rover driver at NASA's Jet Propulsion Laboratory, Pasadena, California. "The rover considers all the paths it could take to get to the designated endpoint for the drive and chooses the best one."

The drive on Tuesday, the mission's 376th Martian day, or "sol," took Curiosity across a depression where ground-surface details had not been visible from the location where the previous drive ended. The drive included about 33 feet (10 meters) of autonomous navigation across hidden ground as part of a day's total drive of about 141 feet (43 meters).

"We could see the area before the dip, and we told the rover where to drive on that part. We could see the ground on the other side, where we designated a point for the rover to end the drive, but Curiosity figured out for herself how to drive the uncharted part in between," said JPL's John Wright, a rover driver.

Curiosity is nearly two months into a multi-month trek from the "Glenelg" area, where it worked for the first half of 2013, to an entry point for the mission's major destination: the lower layers of a 3-mile-tall (5-kilometer-tall) mound called Mount Sharp.

The latest drive brought the distance traveled since leaving Glenelg to 0.86 mile (1.39 kilometers). The remaining distance to the Mount Sharp entry point is about 4.46 miles (7.18 kilometers) along a "rapid transit route." That route was plotted on the basis of images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. The actual driving route, which will be based on images from Curiosity's own cameras, could be longer or shorter.

Curiosity's science team has picked a few waypoints along the rapid transit route to Mount Sharp where driving may be suspended for a few days for science. The rover has about 0.31 mile (500 meters) left to go before reaching the first of these waypoints, which appears from orbiter images to offer exposed bedrock for inspection.

"Each waypoint represents an opportunity for Curiosity to pause during its long journey to Mount Sharp and study features of local interest," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology, Pasadena. "These features are geologically interesting, based on HiRISE images, and they lie very close to the path that provides the most expeditious route to the base of Mount Sharp. We'll study each for several sols, perhaps selecting one for drilling if it looks sufficiently interesting."

After landing inside Gale Crater in August 2012, Curiosity drove eastward to the Glenelg area, where it accomplished the mission's major science objective of finding evidence for an ancient wet environment that had conditions favorable for microbial life. The rover's route is now southwestward. At Mount Sharp, in the middle of Gale Crater, scientists anticipate finding evidence about how the ancient Martian environment changed and evolved.

JPL, a division of Caltech, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.

Click here to visit the NASA/JPL website for the Mars Curiosity mission.

Click here to visit the main NASA website for the Mars Curiosity mission.

Click here to visit the NASA Mars Exploration website for the Mars Curiosity mission.

Click here to follow the mission on Facebook.

Click here to follow the mission on Twitter.


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Tuesday, August 27, 2013

The Sun is About to Flip, Magnetically Speaking

According to the measurements from NASA-supported observatories, something big is about to happen—the sun's vast magnetic field is about to flip. Observations indicate the sun is no more than 3 to 4 months away from a complete magnetic field reversal. And this change is expected to have ripple effects throughout the solar system.

Handle on the Sun (click to enlarge)
The above image was taken September 14, 1999, by the Extreme Ultraviolet Imaging Telescope (EIT). Note the huge, handle-shaped prominence. Taken in the 304 angstrom wavelength, prominences are huge clouds of relatively cool dense plasma suspended in the Sun's hot, thin corona. At times, they can erupt, escaping the Sun's atmosphere. Emission in this spectral line shows the upper chromosphere at a temperature of about 60,000 degrees K. Every feature in the image traces magnetic field structure. The hottest areas appear almost white, while the darker red areas indicate cooler temperatures. Image Credit: NASA/European Space Agency
 
The sun's magnetic field changes polarity approximately every 11 years. It happens at the peak of each solar cycle as the sun's inner magnetic dynamo re-organizes itself. The coming reversal will mark the midpoint of Solar Cycle 24. Half of 'Solar Max' will be behind us, with half yet to come.

The poles are a herald of change. The polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity. This process is a regular part of the solar cycle.

A reversal of the sun's magnetic field is, literally, a big event. The domain of the sun's magnetic influence (also known as the "heliosphere") extends billions of kilometers beyond Pluto. Changes to the field's polarity ripple all the way out to the Voyager probes, on the doorstep of interstellar space.

When solar physicists talk about solar field reversals, their conversation often centers on the "current sheet."  The current sheet is a sprawling surface jutting outward from the sun's equator where the sun's slowly-rotating magnetic field induces an electrical current.  The current itself is small, only one ten-billionth of an amp per square meter (0.0000000001 amps/m2), but there’s a lot of it: the amperage flows through a region 10,000 km thick and billions of kilometers wide.  Electrically speaking, the entire heliosphere is organized around this enormous sheet.

During field reversals, the current sheet becomes very wavy. These undulations have been likened to the seams on a baseball. As Earth orbits the sun, it dips in and out of the current sheet. Transitions from one side to another can stir up stormy space weather around our planet.

Cosmic rays are also affected. These are high-energy particles accelerated to nearly light speed by supernova explosions and other violent events in the galaxy.  Cosmic rays are a danger to astronauts and space probes, and some researchers say they might affect the cloudiness and climate of Earth. The current sheet acts as a barrier to cosmic rays, deflecting them as they attempt to penetrate the inner solar system. A wavy, crinkly sheet acts as a better shield against these energetic particles from deep space.

Observations show that the north pole has already changed sign, while the south pole will soon catch up. Once both poles are reversed, the second half of Solar Max will begin.



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Roaming: Ancient Beijing Observatory

In central Beijing, tucked behind the southwest exit of the Jianguomen subway station, stands a stone platform which rises 14 meters (46 feet) above street level. Surrounded by modern towers and hotels, this ancient structure was the research center for some of the most important scholars of the Ming and Qing dynasties. This is the site of the Ancient Beijing Observatory.
 
The Beijing Ancient Observatory.

Above is a present-day view of the Ancient Beijing Observatory. Image Credit: China Museums (http://chinamuseums.com)

Built in A.D. 1442 during the Ming Dynasty, the observatory offers unique insight into ancient scientific techniques. Though research at the observatory ceased in 1929, it achieved a world record for 487 years of continuous astronomical observation.

But astronomical research in China dates back much farther than this structure. In 1279, the Chinese astronomers WangXun and Guo Shoujing built a small observatory just north of this location. And before that, during the Song Dynasty (960-1279), astronomers created a catalogue of 1848 stars and 283 constellations. And some research dates even farther back, with some astronomical records dating to the Han Dynasty (206 B.C. to A.D. 220).

Astronomy and astrology have historically played a role in the decision-making and planning of China’s emperors. This is because the ancient Chinese believed there was a relationship between the sky and earth, and that observations in the sky could predict wars and accidents. As a result, astronomical research was relegated to upper-class scholars and selected foreign missionaries, and the observatory was not open to the public.

New emperors often ordered a new calendar to be made. Releasing a more accurate calendar was a sign that the new emperor was truly sanctioned by the heavens. Beginning in the Qing Dynasty, more than 100 calendars were produced. The earliest calendars were based on the lunar orbit, but this was not suitable for farming, so in time the solar orbit was added. This lunisolar calendar helped farmers plan their crops. The year was divided into 24 solar terms which predicted the changing of the seasons. In 1281, astronomer Guo Shoujing calculated that one year was 365.2425 days, 300 years before western astronomers made the same discovery and created the Gregorian calendar. The lunisolar calendar system was used until 1911 when the western solar calendar was adopted.

In addition to tracking movements in the sky, astronomers also tracked the wind, rain and snow, making their practice a combination of astronomy, astrology, and meteorology.

From 1669 to 1674, Emperor Kangxi commissioned the Flemish Jesuit missionary Ferdinand Verbiest (1623 – 1688) to design six bronze astronomical instruments, a celestial globe, the equatorial armillary sphere, the ecliptic armillary, the quadrant, the altazimuth and the sextant (it is not known why Verbiest based these instruments on the outmoded designs of Tycho Brahe, as the research of the day was well into the era of telescopic astronomy). In 1715, Killian Stumpf designed two other instruments—the azimuth theodolite, which is a combination of an altazimuth and quadrant and is used to measure the vertical and horizontal angles and altitudes of celestial bodies. In 1744, Emperor Qianlong ordered the construction of the last astronomical instrument—the new armillary sphere—to be added to the ancient observatory. These instruments occupied the roof of the observatory, while the older instruments were moved to the yard below.

All of the observatory's instruments except the altazimuth theodolite are adorned with bronze dragons at the base, signifying that astronomy was a special discipline for the emperor. A telescope was never added to the collection, although the emperor acquired one and kept it at the palace for personal use. The observatory was raided in 1900 during the Eight-Nation Alliance's siege of Beijing, and the instruments were taken by foreign troops. The French returned five of the instruments the next year, while the Germans took five of them to Europe to display at Potsdam Hall. They were finally returned in 1921. Several of the instruments were sent to Nanjing for safekeeping after the Japanese invaded China.

The site was opened to the public as a museum in 1983. It is operated in conjunction with the Beijing Planetarium and currently receives about 500 visitors per week. There are detailed English descriptions available. In the courtyards surrounding the Ancient Observatory, there are three exhibitions about the history of astronomy in China, the uses of the various instruments and examples of ancient instruments such as water clocks and sundials. Visitors can also climb to the top of the observatory, which has 99 steps to signify a relationship to the emperor. There they can look at additional instruments displayed on the roof.

To learn more about Ancient Beijing Observatory, click here to visit the website of the Beijing Planetarium.

To learn more about Ancient Beijing Observatory, click here to visit China’s travel website.


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Monday, August 26, 2013

Robert Samuel Kraemer, 1928 - 2013

Robert S. Kraemer with a model of NASA/JPL's Viking orbiter-lander. Image Credit: Rogers Photo Archive

Robert Samuel Kraemer, NASA’s former director of planetary exploration who was also an expert in rocket engines, died August 20 at an assisted living center in Catonsville, Maryland. He was 84. The cause was complications from a fall at his home two months ago.

Kraemer joined NASA in 1967 and, in one of his early assignments, managed the development of a Mars surface laboratory mission at NASA’s headquarters in Washington.  After the project was canceled because of congressional concerns, he was appointed manager of advanced planetary programs and technology and in 1970 was named director of planetary programs. Kraemer oversaw the successful completion of 12 missions to launch spacecraft into the solar system to study its planets, moons and more. He faced political, financial and technical challenges in managing an unprecedented surge of planetary exploration that produced groundbreaking results. Kraemer was associated with the missions Mariner 9 and 10, Pioneer 10 and 11, Helios 1 and 2, Viking 1 and 2, Voyager 1 and 2 and Pioneer Venus 1 and 2. Kraemer was described as a very technically competent and a very good engineer, and he was very good at picking the right people for the right job.

The son of a citrus rancher and a homemaker, Kraemer was born on October 21, 1928, in Fullerton, California, and raised in Placentia, Calif. He received a bachelor’s degree in aeronautical engineering from the University of Notre Dame in 1950.

After receiving a master’s degree in aeronautics and rocket propulsion from the California Institute of Technology in 1951, he worked for North American Aviation’s Rocketdyne Division in Canoga Park, California, on rocket propulsion for a secret intercontinental cruise missile called Navaho.

After Rocketdyne, Kraemer then worked as chief engineer for space systems at Ford Aeronutronic in Newport Beach, California, where he worked until he joined NASA. He retired in 1990.

Kraemer wrote several books, including Rocketdyne: Powering Humans into Space and Beyond the Moon: A Golden Age of Planetary Exploration 1971-1981. He received the Distinguished Service Medal, NASA’s highest honor.

Kraemer lived in Rockville from 1967 to 1981, when he moved to Annapolis. Since 2007, he had lived in Catonsville.

Kraemer is survived by his wife of 59 years, Anne Park Kraemer of Catonsville; six children, David Kraemer and Anita Kraemer, both of Catonsville, Timothy Kraemer of Germantown, Md., Stephen Kraemer of Athens, Ga., Kathryn McCoy of Kensington and Joan Compere of Ellicott City; two brothers; a sister; and 11 grandchildren.


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Kepler Looking for Work

NASA has ended Kepler's primary and extended missions. But much mission data is still to be analyzed and NASA is seeking a new purpose for the space telescope.


Kepler
Above is a reaction wheel (in its housing), identical to those used aboard NASA's Kepler Space Telescope. Kepler launched with four working wheels. Image Credit: Ball Aerospace & Technologies Corporation

Following months of analysis and testing, NASA's Kepler Space Telescope team ended its attempts to restore the spacecraft to full working order, and now is considering what new science research it can carry out in its current condition.

Two of Kepler's four gyroscope-like reaction wheels, which are used to precisely point the spacecraft, have failed. The first was lost in July 2012, and the second in May. Engineers' efforts to restore at least one of the wheels have been unsuccessful.

Kepler completed its prime mission in November 2012 and then began its four-year extended mission. However, the spacecraft needs three functioning wheels to continue its search for Earth-sized exoplanets, which are planets outside our solar system, orbiting stars like our sun in what's known as the habitable zone -- the range of distances from a star where the surface temperature of a planet might be suitable for liquid water. As scientists analyze previously collected data, the Kepler team also is looking into whether the space telescope can conduct a different type of science program, potentially including an exoplanet search, using the remaining two good reaction wheels and thrusters.

"Kepler has made extraordinary discoveries in finding exoplanets including several super-Earths in the habitable zone," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. "Knowing that Kepler has successfully collected all the data from its prime mission, I am confident that more amazing discoveries are on the horizon."

On August 8th, engineers conducted a system-level performance test to evaluate Kepler's current capabilities. They determined wheel 2, which failed last year, can no longer provide the precision pointing necessary for science data collection. The spacecraft was returned to its point rest state, which is a stable configuration where Kepler uses thrusters to control its pointing with minimal fuel use.

"At the beginning of our mission, no one knew if Earth-size planets were abundant in the galaxy. If they were rare, we might be alone," said William Borucki, Kepler science principal investigator at NASA's Ames Research Center in Moffett Field, California. "Now at the completion of Kepler observations, the data holds the answer to the question that inspired the mission: Are Earths in the habitable zone of stars like our sun common or rare?"

An engineering study will be conducted on the modifications required to manage science operations with the spacecraft using a combination of its remaining two good reaction wheels and thrusters for spacecraft attitude control.

Informed by contributions from the broader science community in response to the call for scientific white papers announced August 2nd, the Kepler project team will perform a study to identify possible science opportunities for a two-wheel Kepler mission.

Depending on the outcome of these studies, which are expected to be completed later this year, NASA will assess the scientific priority of a two-wheel Kepler mission. Such an assessment may include prioritization relative to other NASA astrophysics missions competing for operational funding at the NASA Senior Review board early next year.

From the data collected in the first half of its mission, Kepler has confirmed 135 exoplanets and identified over 3,500 candidates. The team continues to analyze all four years of collected data, expecting hundreds, if not thousands, of new discoveries including the long-awaited Earth-size planets in the habitable zone of sun-like stars. Though the spacecraft will no longer operate with its unparalleled precision pointing, scientists expect Kepler’s most interesting discoveries are still to come.

Meanwhile, preparations are underway for hosting the second Kepler Science Conference November 4-8, at NASA's Ames Research Center. This will be an opportunity to share not only the investigations of the Kepler project team, but also those of the wider science community using publicly accessible data from Kepler.

Ames is responsible for the Kepler mission concept, ground system development, mission operations, and science data analysis. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development.

Ball Aerospace & Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA's 10th Discovery Mission and was funded by the agency's Science Mission Directorate.

Click here to learn more about Kepler's upcoming science conference.

Click here to learn more about NASA's call for two-wheel science proposals.

Click here to learn more about NASA's Kepler spacecraft.



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Sunday, August 25, 2013

Asteroid 1998 KN3 Caught by NEOWISE

During the first NEOWISE mission, the WISE spacecraft caught an image of near-Earth asteroid 1998 KN3 as it passed in front of the Orion nebula.

Image Credit: NASA/JPL-Caltech

The above image shows the potentially hazardous near-Earth object 1998 KN3 as it zips past a cloud of dense gas and dust near the Orion nebula. NEOWISE, the asteroid-hunting portion of the Wide-field Infrared Survey Explorer, or WISE, mission, snapped infrared pictures of the asteroid, seen as the yellow-green dot at upper left. Because asteroids are warmed by the sun to roughly room temperature, they glow brightly at the infrared wavelengths used by WISE.

Astronomers use infrared light from asteroids to measure their sizes, and when combined with visible-light observations, they can also measure the reflectivity of their surfaces. The WISE infrared data reveal that this asteroid is about .7 mile (1.1 kilometers) in diameter and reflects only about 7 percent of the visible light that falls on its surface, which means it is relatively dark.

In this image, blue denotes shorter infrared wavelengths, and red, longer. Hotter objects emit shorter-wavelength light, so they appear blue. The blue stars, for example, have temperatures of thousands of degrees. The coolest gas and dust appears red. The asteroid appears yellow in the image because it is about room temperature: cooler than the distant stars, but warmer than the dust.

The currently-hibernating WISE spacecraft is scheduled to be revived in September to resume the NEOWISE mission. Its goal will be to discover and characterize more near-Earth objects (NEOs), space rocks that can be found orbiting within 28 million miles (45 million kilometers) from Earth's path around the sun. NASA anticipates WISE will use its 16-inch (40-centimeter) telescope and infrared cameras to discover about 150 previously unknown NEOs and characterize the size, albedo and thermal properties of about 2,000 others -- including some which could be candidates for the agency's recently announced asteroid initiative.

JPL manages the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate, Washington. The principal investigator, Edward Wright, is at UCLA. The mission was competitively selected under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

Click here to learn more about the NEOWISE mission.

Click here to learn more about the asteroid initiative.


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Happy 10th Birthday, Spitzer!

Launched August 25th, 2003, The Spitzer Space Telescope is celebrating ten years of discoveries. And it's still going strong.

A montage of images taken by NASA's Spitzer Space Telescope over the years.
Above is a montage of images taken by NASA's Spitzer Space Telescope over the years. Image Credit: NASA/JPL-Caltech
Ten years after a Delta II rocket launched NASA's Spitzer Space Telescope, lighting up the night sky over Cape Canaveral, Fla., the fourth of the agency's four Great Observatories continues to illuminate the dark side of the cosmos with its infrared eyes.

The telescope studied comets and asteroids, counted stars, scrutinized planets and galaxies, and discovered soccer-ball-shaped carbon spheres in space called buckyballs. Moving into its second decade of scientific scouting from an Earth-trailing orbit, Spitzer continues to explore the cosmos near and far. One additional task is helping NASA observe potential candidates for a developing mission to capture, redirect and explore a near-Earth asteroid.

"President Obama's goal of visiting an asteroid by 2025 combines NASA's diverse talents in a unified endeavor," said John Grunsfeld, NASA's associate administrator for science in Washington. "Using Spitzer to help us characterize asteroids and potential targets for an asteroid mission advances both science and exploration."

Spitzer's infrared vision lets it see the far, cold and dusty side of the universe. Close to home, the telescope has studied the comet dubbed Tempel 1, which was hit by NASA's Deep Impact mission in 2005. Spitzer showed the composition of Tempel 1 resembled that of solar systems beyond our own. Spitzer also surprised the world by discovering the largest of Saturn's many rings. The enormous ring, a wispy band of ice and dust particles, is very faint in visible light, but Spitzer's infrared detectors were able to pick up the glow from its heat.

Perhaps Spitzer's most astonishing finds came from beyond our solar system. The telescope was the first to detect light coming from a planet outside our solar system, a feat not in the mission's original design. With Spitzer's ongoing studies of these exotic worlds, astronomers have been able to probe their composition, dynamics and more, revolutionizing the study of exoplanet atmospheres.
 Other discoveries and accomplishments of the mission include getting a complete census of forming stars in nearby clouds; making a new and improved map of the Milky Way's spiral-arm structure; and, with NASA's Hubble Space Telescope, discovering that the most distant galaxies known are more massive and mature than expected.

"I always knew Spitzer would work, but I had no idea that it would be as productive, exciting and long-lived as it has been," said Spitzer project scientist Michael Werner of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who helped conceive the mission. "The spectacular images that it continues to return, and its cutting-edge science, go far beyond anything we could have imagined when we started on this journey more than 30 years ago."

In October, Spitzer will attempt infrared observations of a small near-Earth asteroid named 2009 DB to better determine its size, a study that will assist NASA in understanding potential candidates for the agency's asteroid capture and redirection mission. This asteroid is one of many candidates the agency is evaluating.

Spitzer, originally called the Space Infrared Telescope Facility, was renamed after its launch in honor of the late astronomer Lyman Spitzer. Considered the father of space telescopes, Lyman Spitzer began campaigning to put telescopes in space, away from the blurring effects of Earth's atmosphere, as early as the 1940s. His efforts also led to the development and deployment of NASA's Hubble Space Telescope, carried to orbit by the space shuttle in 1990.

In anticipation of the Hubble launch, NASA set up the Great Observatories program to fly a total of four space telescopes designed to cover a range of wavelengths: Hubble, Spitzer, the Chandra X-ray Observatory and the now-defunct Compton Gamma Ray Observatory.

"The majority of our Great Observatory fleet is still up in space, each with its unique perspective on the cosmos," said Paul Hertz, Astrophysics Division director at NASA headquarters in Washington. "The wisdom of having space telescopes that cover all wavelengths of light has been borne out by the spectacular discoveries made by astronomers around the world using Spitzer and the other Great Observatories."

Spitzer ran out of the coolant needed to chill its longer-wavelength instruments in 2009, and entered the so-called warm mission phase. Now, after its tenth year of peeling back the hidden layers of the cosmos, its journey continues.

"I get very excited about the serendipitous discoveries in areas we never anticipated," said Dave Gallagher, Spitzer's project manager at JPL from 1999 to 2004, reminding him of a favorite quote from Marcel Proust: "The real voyage of discovery consists not in seeking new landscapes, but in having new eyes."

JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech. Caltech manages JPL for NASA.

Click here to visit the Caltech site for the Spitzer mission.

Click here to visit the NASA site for the Spitzer mission.


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Saturday, August 24, 2013

Radar Photoshoot of Asteroid 2005 WK4

Radar images of asteroid 2005 WK4 were obtained on Aug. 8, 2013.
Radar images of asteroid 2005 WK4 were obtained on August 8, 2013. The asteroid is between 660 - 980 feet (200 - 300 meters) in diameter. Image credit: NASA/JPL-Caltech/GSSR

On August 8th, a collage of radar images of near-Earth asteroid 2005 WK4 was generated by NASA scientists using the 230-foot (70-meter) Deep Space Network antenna at Goldstone, California.

The asteroid is between 660 and 980 feet (200 and 300 meters) in diameter; it has a rounded and slightly asymmetric shape. As it rotates, a number of features are evident that suggest the presence of some flat regions and a bulge near the equator.

The data were obtained between 12:40 and 7:10 a.m. PDT (3:40 and 10:10 a.m. EDT). At the time of the observations, the asteroid's distance was about 1.93 million miles (3.1 million kilometers) from Earth, which is 8.2 lunar distances away. The data were obtained over an interval of 6.5 hours as the asteroid completed about 2.4 rotations. The resolution is 12 feet (3.75 meters) per pixel.

Radar is a powerful technique for studying an asteroid's size, shape, rotation state, surface features and surface roughness, and for improving the calculation of asteroid orbits. Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than if radar observations weren't available.

NASA places a high priority on tracking asteroids and protecting our home planet from them. In fact, the United States has the most robust and productive survey and detection program for discovering near-Earth objects. To date, U.S. assets have discovered more than 98 percent of the known near-Earth Objects.

In addition to the resources NASA puts into understanding asteroids, it also partners with other U.S. government agencies, university-based astronomers, and space science institutes across the country that are working to track and understand these objects better, often with grants, interagency transfers and other contracts from NASA.

In 2016, NASA will launch a robotic probe to one of the most potentially hazardous of the known near-Earth objects. The OSIRIS-REx mission to asteroid (101955) Bennu will be a pathfinder for future spacecraft designed to perform reconnaissance on any newly discovered threatening objects. Aside from monitoring potential threats, the study of asteroids and comets enables a valuable opportunity to learn more about the origins of our solar system, the source of water on Earth, and even the origin of organic molecules that led to the development of life.

NASA recently announced development of a first-ever mission to identify, capture and relocate an asteroid for human exploration. Using game-changing technologies, this mission would mark an unprecedented technological achievement that raises the bar of what humans can do in space.

NASA's Near-Earth Object Program at NASA Headquarters, Washington, manages and funds the search, study and monitoring of asteroids and comets whose orbits periodically bring them close to Earth. JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.

Click here to learn more about the Near-Earth Object Program.

Click here to learn more about Asteroid Watch.

Click here to visit the Asteroid Watch Twitter page.

Click here to learn more about asteroid radar research.

Click here to learn more about NASA's Deep Space Network.



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Friday, August 23, 2013

NEOWISE is Coming Back!

Back to Hunt More Asteroids
Above is an artist's concept of the Wide-field Infrared Survey Explorer, or WISE spacecraft, in orbit around Earth. In September of 2013, engineers will attempt to bring the mission out of hibernation to hunt for more asteroids and comets in a project called NEOWISE. Image credit: NASA/JPL-Caltech

One NASA spacecraft performed an infrared survey of the sky, discovered and characterized tens of thousands of asteroids, and then went into hibernation. This same craft is coming back for more. It will return to service for three more years starting in September, assisting the agency in its effort to identify the population of potentially hazardous near-Earth objects, as well as those suitable for asteroid exploration missions. 

The Wide-field Infrared Survey Explorer (WISE) will be revived with the goal of discovering and characterizing near-Earth objects (NEOs), space rocks that can be found orbiting within 28 million miles (45 million kilometers) from Earth's path around the sun. NASA anticipates WISE will use its 16-inch (40-centimeter) telescope and infrared cameras to discover about 150 previously unknown NEOs and characterize the size, albedo and thermal properties of about 2,000 others -- including some which could be candidates for the agency's recently announced asteroid initiative. 

"The WISE mission achieved its mission's goals and as NEOWISE extended the science even further in its survey of asteroids. NASA is now extending that record of success, which will enhance our ability to find potentially hazardous asteroids, and support the new asteroid initiative," said John Grunsfeld, NASA's associate administrator for science in Washington. "Reactivating WISE is an excellent example of how we are leveraging existing capabilities across the agency to achieve our goal." 

NASA's asteroid initiative will be the first mission to identify, capture and relocate an asteroid. It represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet. The asteroid initiative brings together the best of NASA's science, technology and human exploration efforts to achieve President Obama's goal of sending humans to an asteroid by 2025. 

Launched in December 2009 to look for the glow of celestial heat sources from asteroids, stars and galaxies, WISE made about 7,500 images every day during its primary mission, from January 2010 to February 2011. As part of a project called NEOWISE, the spacecraft made the most accurate survey to date of NEOs. NASA turned most of WISE's electronics off when it completed its primary mission. 

"The data collected by NEOWISE two years ago have proven to be a gold mine for the discovery and characterization of the NEO population," said Lindley Johnson, NASA's NEOWISE program executive in Washington. "It is important that we accumulate as much of this type of data as possible while the WISE spacecraft remains a viable asset." 

Because asteroids reflect but do not emit visible light, infrared sensors are a powerful tool for discovering, cataloging and understanding the asteroid population. Depending on an object's reflectivity, or albedo, a small, light-colored space rock can look the same as a big, dark one. As a result, data collected with optical telescopes using visible light can be deceiving. 

During 2010, NEOWISE observed about 158,000 rocky bodies out of approximately 600,000 known objects. Discoveries included 21 comets, more than 34,000 asteroids in the main belt between Mars and Jupiter, and 135 near-Earth objects. 

The WISE prime mission was to scan the entire celestial sky in infrared light. It captured more than 2.7 million images in multiple infrared wavelengths and cataloged more than 560 million objects in space, ranging from galaxies faraway to asteroids and comets much closer to Earth. 

"The team is ready and after a quick checkout, we're going to hit the ground running," said Amy Mainzer, NEOWISE principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "NEOWISE not only gives us a better understanding of the asteroids and comets we study directly, but it will help us refine our concepts and mission operation plans for future, space-based near-Earth object cataloging missions." 

JPL manages WISE for NASA's Science Mission Directorate at the agency's headquarters in Washington. The mission is part of NASA's Explorers Program, which NASA's Goddard Space Flight Center in Greenbelt, Md., manages. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. 

Click here to learn more about the NEOWISE mission.

Click here to learn more about the asteroid initiative.


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Thursday, August 22, 2013

Waved at Saturn? Maybe You're in the Collage!

Earth Waves at Cassini
Above is a collage of only some of the images shared via Twitter, Facebook, Flickr, Instagram, Google+, and email. NASA's Cassini mission team assembled the collage, using an image of Earth as the base image. Image Credit: NASA/JPL-Caltech

People around the world shared more than 1,400 images of themselves as part of the Wave at Saturn event organized by NASA's Cassini mission on July 19the day the Cassini spacecraft turned back toward Earth to take our picture. The images were posted online from 40 countries and 30 U.S. states via Twitter, Facebook, Flickr, Instagram, Google+, and email.

"Thanks to all of you, near and far, old and young, who joined the Cassini mission in marking the first time inhabitants of Earth had advance notice that our picture was being taken from interplanetary distances," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "While Earth is too small in the images Cassini obtained to distinguish any individual human beings, the mission has put together this collage so that we can celebrate all your waving hands, uplifted paws, smiling faces and artwork."

From its perch in the Saturn system, Cassini took a picture of Earth as part of a larger set of images it was collecting of the Saturn system. Scientists are busy putting together the color mosaic of the Saturn system, which they expect will take at least several more weeks to complete. The scientists who study Saturn's rings are poring over visible-light and infrared data obtained during that campaign.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

Click here to learn more about the Wave at Saturn campaign.

Click here to learn more about NASA's Cassini mission.


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Wednesday, August 21, 2013

Studying Starbirth in Herbig-Haro 46/47 with ESO's ALMA

Herbig-Haro 46/47, as seen by the Atacama Large Millimeter/submillimeter Array (ALMA). Image Credit: ALMA/ESO

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have obtained a vivid close-up view of material streaming away from a newborn star. By looking at the glow coming from carbon monoxide molecules in an object called Herbig-Haro 46/47 they have discovered that its jets are even more energetic than previously thought. The very detailed new images have also revealed a previously unknown jet pointing in a totally different direction.

Young stars are violent objects that eject material at speeds as high as one million kilometres per hour. When this material crashes into the surrounding gas it glows, creating a Herbig-Haro object, named for astronomers George Herbig and Guillermo Haro, who did the first detailed studies of these objects. A spectacular example is named Herbig-Haro 46/47 and is situated about 1400 light-years from Earth in the southern constellation of Vela (The Sails). This object was the target of a study using ALMA during the Early Science phase, whiles the telescope was still under construction and well before the array was completed.

The new images reveal fine detail in two jets, one coming toward Earth and one moving away. The receding jet was almost invisible in earlier pictures made in visible light, due to obscuration by the dust clouds surrounding the new-born star. ALMA has not only provided much sharper images than earlier facilities but also allowed astronomers to measure how fast the glowing material is moving through space.

These new observations of Herbig-Haro 46/47 revealed that some of the ejected material had velocities much higher than had been measured before. This means the outflowing gas carries much more energy and momentum than previously thought.

The team leader and first author of the new study, H├ęctor Arce (Yale University, USA) explains that "ALMA's exquisite sensitivity allows the detection of previously unseen features in this source, like this very fast outflow. It also seems to be a textbook example of a simple model where the molecular outflow is generated by a wide-angle wind from the young star."

The observations were obtained in just five hours of ALMA observation time – even though ALMA was still under construction at the time – similar quality observations with other telescopes would have taken ten times longer.

"The detail in the Herbig-Haro 46/47 images is stunning. Perhaps more stunning is the fact that, for these types of observations, we really are still in the early days. In the future ALMA will provide even better images than this in a fraction of the time," adds Stuartt Corder (Joint ALMA Observatory, Chile), a co-author on the new paper.

Diego Mardones (Universidad de Chile), another co-author, emphasises that "this system is similar to most isolated low mass stars during their formation and birth. But it is also unusual because the outflow impacts the cloud directly on one side of the young star and escapes out of the cloud on the other. This makes it an excellent system for studying the impact of the stellar winds on the parent cloud from which the young star is formed."

The sharpness and sensitivity achieved by these ALMA observations also allowed the team to discover an unsuspected outflow component that seems to be coming from a lower mass companion to the young star. This secondary outflow is seen almost at right angles to the principal object and is apparently carving its own hole out of the surrounding cloud.

Arce concludes that "ALMA has made it possible to detect features in the observed outflow much more clearly than previous studies. This shows that there will certainly be many surprises and fascinating discoveries to be made with the full array. ALMA will certainly revolutionize the field of star formation!"

To learn more, click here to visit website of the European Southern Observatory.


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Tuesday, August 20, 2013

Happy 36th Birthday, Voyager 2!

Voyager 2 was launched on August 20th, 1977, from the NASA Kennedy Space Center at Cape Canaveral in Florida, propelled into space on a Titan/Centaur rocket. Image Credit: NASA/JPL-Caltech

Voyager 2 was launched on August 20th, 1977, from the NASA Kennedy Space Center at Cape Canaveral in Florida, propelled into space on a Titan/Centaur rocket. (Image Credit: NASA/JPL)

The Voyager 2 spacecraft was launched on August 20, 1977. It was built (along with its identical twin Voyager 1) to explore the outer planets of our solar system – namely Jupiter, Saturn, Uranus and Neptune. It did all that, and to this day is the only spacecraft to visit Uranus and Neptune. On top of that, Voyager 2 is the longest operating spacecraft in human history. It surpassed Pioneer 6, which launched on December 16, 1965, and sent its last signal back to NASA’s Deep Space Network on December 8, 2000.

Today, Voyager 2 is over 15.2 billion kilometers from Earth. At the speed of light, it would take about 14 hours to get from Earth to Voyager 2.

Voyager 1's 36th birthday will be September 5, 2012 – and in spite of launching a couple weeks after Voyager 2, Voyager 1 is even further away: Voyager 1 is over 18.6 billion kilometers away from Earth, or over 17 hours of light-travel time.

The Voyager mission was planned because of an uncommon alignment of the four outer planets – Jupiter, Saturn, Uranus, and Neptune – which allowed all the planets to be visited in a single mission. Voyager 1 visited Jupiter and Saturn and then used a gravity assist/slingshot from Saturn and headed north – directly towards the edge of the solar system. Voyager 2 took a less direct route to the edge (which explains why it isn’t as far away) visiting Jupiter, Saturn, Uranus, and finally Neptune before using a gravity assist/slingshot to head towards the edge of the solar system in a southerly direction.

Both Voyagers are currently in a region of space called the Heliopause, which is the outermost layer of the Heliosphere where the solar wind is slowed by the pressure of interstellar gas. They are on the very edge of our solar system, and based on the data that the spacecraft are sending back to Earth, it is suspected that they will “break through” into interstellar space in the very near future (“near future” meaning it could be months or a few years). Some think Voyager 1 has transitioned into interstellar space, though more data and time is needed to determine that. Both spacecraft are travelling about 60,000km/h, though Voyager 1 is travelling slightly faster than Voyager 2. Their radioisotope thermoelectric generators will be able to sustain sufficient electrical output to operate until 2020, or possibly until 2025.

Some key dates for Voyager 1:

Launch: September 5, 1977
Closest approach to Jupiter (349,000km): March 5, 1979
Closest approach to Saturn (124,000km): November 12, 1979
Took the famous “family portrait” and “pale blue dot” images (6 billion + km): February-June 1990

Some key dates for Voyager 2:

Launch: August 20, 1977
Closest approach to Jupiter (570,000km): July 9, 1979
Closest approach to Saturn (100,800km): August 26, 1981
Closest approach to Uranus (81,500km): January 24, 1986
Closest approach to Neptune (4,800km): August 25, 1989 – yes you read that correctly…Voyager 2 passed a mere 4,800km above Neptune’s north pole!

Click here to visit the NASA/JPL Project Voyager Mission site.


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Seasonal Blue Moon August 20, 2013

The Galileo spacecraft sent back this image of the Moon as it headed into the outer solar system. The distinct bright ray crater at the bottom of the image is the Tycho impact basin. Image Credit: NASA/JPL-Caltech

Tuesday evening, August 20th, we will see the rise of a full moon. It will reach a peak at 9:45 PM ET. But the title of "blue moon" has more to do with frequency than with color. A traditional blue moon is the appearing of a second full moon phase in a given calendar month. There is usually at least one blue moon in each calendar year, and there are two blue moons every 19 years.

But wait! The moon goes through its cycle of phases very 29.5 days and this full moon is on the 20th of the month. So this is cannot be the second full moon for August, and so is not a traditional blue moon. What gives?

This particular full moon is a "seasonal blue moon"—the third of four full moons in a season. This will be the first seasonal blue moon in nearly three years. After this one, the next seasonal blue moon will not occur until 2015.

Usually, when the moon is full, it passes either above or below Earth’s shadow, but sometimes, when it is perfectly aligned, it travels right through the shadow. This event is called a lunar eclipse. And depending on how well the earth, moon and sun are aligned, it could be a total or partial eclipse.


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