Europa Clipper Mission Teleconference

 On Monday, September 9, NASA will hold a media teleconference to provide an update on the Europa Clipper mission, that will study whether Jupiter’s moon Europa could be hospitable to life. The teleconference will occur after a key decision point meeting earlier that day regarding next steps for the mission. The teleconference can be watched here: https://www.nasa.gov/live/

If you would like information on the Europa mission and the spacecraft, I have a book for you! The book is called Journey to Europa: The NASA Europa Clipper Mission, and it is available in Kindle and paperback form. Click on the image below to check it out!

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Potential Sign of Life on Venus

Artist's concept of the thick clouds that obscure Venus’ surface. Image Credit: ESO/M. Kornmesser & NASA/JPL/Caltech

An international team of astronomers have confirmed that the cloud tops of Venus contain traces of phosphine, a gas that is produced by microbial life. The gas is also produced by some Earth-based industrial processes. That said, no known non-biological processes can create phosphine in the conditions found on Venus.

The find raises two intriguing possibilities: One, the possibility that Venus may harbor life in its clouds. And two, the phosphine could be the result of some unknown chemical process, which would be an enticing subject of scientific study.

You may read the full article at Astronomy.com

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Martian Clay Found

The Curiosity rover selfie is composed of 57 individual images taken by the rover's Mars Hand Lens Imager (MAHLI), a camera on the end of the rover's robotic arm. The images are stitched together into a panorama, and the robotic arm is digitally removed. Image credit: NASA/JPL-Caltech/MSSS

NASA's Mars Curiosity rover confirmed that the region it's exploring, called the "clay-bearing unit," prooved to be an accurate name. Two samples the rover recently drilled at rock targets called "Aberlady" and "Kilmarie" have revealed the highest amounts of clay minerals found during the mission. Both drill targets appear in a new selfie taken by the rover on May 12, 2019, the 2,405th Martian day, or sol, of the mission.

The region is located on the side of lower Mount Sharp and stood out to NASA orbiters before Curiosity landed in 2012. Clay often forms in water, which is essential for life; Curiosity is exploring Mount Sharp to see if it had the conditions to support life billions of years ago. The rover's mineralogy instrument, called CheMin (Chemistry and Mineralogy), provided the first analyses of rock samples drilled in the clay-bearing unit. CheMin also found very little hematite, an iron oxide mineral that was abundant just to the north, on Vera Rubin Ridge.

Other than proof that there was a significant amount of water once in Gale Crater, what these new findings mean for the region is still up for debate. It's likely that the rocks in the area formed as layers of mud in ancient lakes - something Curiosity also found lower on Mount Sharp. Water interacted with sediment over time, leaving an abundance of clay in the rocks there.

Amid this new drilling and analyzing, Curiosity took a break to watch some clouds - all in the name of science. The rover used its black-and-white Navigation Cameras (Navcams) to snap images of drifting clouds on May 7 and May 12, 2019, sols 2400 and 2405. They're likely water-ice clouds about 19 miles (31 kilometers) above the surface.

The mission's team has been trying to coordinate cloud observations with NASA's InSight lander, located about 373 miles (600 kilometers) away, which recently took its own cloud images. Capturing the same clouds from two vantage points can help scientists calculate their altitude.

More information about Curiosity is at: https://mars.nasa.gov/msl/

More information about Mars is at: https://mars.nasa.gov/

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Happy Birthday, Pioneer 10!

Pioneer 10 was launched March 2, 1972. Shown, artist rendering of Pioneer 10 flyby of Jupiter. Image credit, NASA.

March 2 marks a birthday, of sorts, for NASA's Pioneer 10 mission. On this day in 1972, the spacecraft was launched on the first mission to the planet Jupiter.

Originally designated Pioneer F, the spacecraft weighed 258 kilograms (569 pounds), completed the first mission to the planet Jupiter and, later, became the first of five artificial objects to achieve the escape velocity that will allow them to leave the Solar System. The project was conducted by the NASA Ames Research Center in California, and the space probe was manufactured by TRW Inc.

The spacecraft was launched on March 2, 1972 by an Atlas-Centaur expendable vehicle from Launch Complex 36A at Cape Canaveral, Florida. Between July 15, 1972, and February 15, 1973, it became the first spacecraft to traverse the asteroid belt. Photography of Jupiter began November 6, 1973, at a range of 25,000,000 kilometers (16,000,000 mi), and a total of about 500 images were transmitted. The closest approach to the planet was on December 4, 1973, at a range of 132,252 kilometers (82,178 mi). During the mission, the on-board instruments were used to study the asteroid belt, the environment around Jupiter, the solar wind, cosmic rays, and eventually the far reaches of the Solar System and heliosphere.

Pioneer 10 crossed the orbit of Saturn in 1976 and the orbit of Uranus in 1979. On June 13, 1983, the craft crossed the orbit of Neptune, the outermost planet, and so became the first human-made object to leave the proximity of the major planets of the Solar System. The mission came to an official end on March 31, 1997, when it had reached a distance of 67 AU from the Sun, though the spacecraft was still able to transmit coherent data after this date.

After March 31, 1997, Pioneer 10's weak signal continued to be tracked by the Deep Space Network to aid the training of flight controllers in the process of acquiring deep space radio signals. There was an Advanced Concepts study applying chaos theory to extract coherent data from the fading signal.

The last successful reception of telemetry was received from Pioneer 10 on April 27, 2002; subsequent signals were barely strong enough to detect, and provided no usable data. The final, very weak signal from Pioneer 10 was received on January 23, 2003 when it was 12 billion kilometers (80 AU) from Earth. Further attempts to contact the spacecraft were unsuccessful. A final attempt was made on the evening of March 4, 2006, the last time the antenna would be correctly aligned with Earth. No response was received from Pioneer 10. NASA decided that the RTG units (the spacecraft's power generators) had probably fallen below the power threshold needed to operate the transmitter. Hence, no further attempts at contact were made.

To learn more about Pioneer 10 and the NASA Pioneer missions, visit these sites.

NASA Pioneer Missions

Web Archive of the NASA Pioneer Mission Home Page

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Phoenix Mars Lander Is a Bit Dusty

The above animation "blinks" between two images: One taken May 25, 2008, the other taken December 21, 2017. Both show the landing site for NASA's Phoenix Mars Lander. The later image shows the result of dust layering. Image credit: NASA/JPL-Caltech/Univ. of Arizona

A late 2017 image of NASA's Phoenix Mars mission, which landed nearly a decade ago in the norther regions of Mars, shows that dust has covered some marks of the landing.

The Phoenix lander itself, plus its back shell and parachute, are still visible in the image taken December 21, 2017, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. But an animated-blink comparison with an image from about two months after the May 25, 2008, landing shows that patches of ground that had been darkened by removal of dust during landing events have become coated with dust again.

In August 2008, Phoenix completed its three-month mission studying Martian ice, soil and atmosphere. The lander worked for two additional months before reduced sunlight caused energy to become insufficient to keep the lander functioning. The solar-powered robot was not designed to survive through the dark and cold conditions of a Martian arctic winter.

Both images in the animation were taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. The one with three patches of darker ground -- where landing events removed dust -- was taken on July 20, 2008. The one with a more even coating of pale dust throughout the area was taken on December 21, 2017. Both image cover an area roughly 300 meters wide at 68 degrees north latitude, 234 degrees east longitude.

The University of Arizona, Tucson, led the Phoenix mission and also operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, managed the Phoenix Mars Lander Project and manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin Space, Denver, built both the Phoenix and Mars Reconnaissance Orbiter spacecraft.

For more information on the Phoenix Mars Lander, the Mars Reconnaissance Orbiter mission and NASA's Mars exploration program, check out these site.

Phoenix Mars Lander Mission

Mars Reconnaissance Orbiter Mission

NASA's Mars Exploration Program

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The Rings of Saturn Viewed Planet-Side and the Final Days of Cassini

On August 20, NASA's Cassini spacecraft completed another pass between Saturn and its rings. The below animation shows the ring system from above (sunlit side) and then below (shadow side). All of the ring system is seen. But due to the angle, the rings and the ring divisions appear foreshortened (squeezed together). Also, the inner C ring looks larger in the foreground.

Saturn's ring system as seen during the Cassini pass between the rings and Saturn on August 20, 2017. Image Credit: NASA/JPL-Caltech/Space Science Institute

The Grand Finale is Nearly Complete

The spacecraft is quickly approaching its  mission-ending dive into the atmosphere of Saturn on September 15. An April 22 gravitational assist from Saturn's moon Titan put the craft on its final path. But several mission milestones remain before then.

The spacecraft is expected to lose radio contact with Earth within about one to two minutes after beginning its descent into Saturn's upper atmosphere. But on the way down, eight of Cassini's 12 science instruments will be operating. In particular, the spacecraft's ion and neutral mass spectrometer (INMS), which will be directly sampling the atmosphere's composition, potentially returning insights into the giant planet's formation and evolution. On the day before, September 14, other Cassini instruments will make detailed, high-resolution observations of Saturn's auroras, temperature, and the vortices at the planet's poles. Cassini's imaging camera will take it's last views on September 14 and then be shut down. Below are some highlights from the final days of Cassini.

September 9 -- Cassini will make the last of 22 passes between Saturn itself and its rings -- closest approach is 1,044 miles (1,680 kilometers) above the clouds tops.

September 11 -- Cassini will make a distant flyby of Saturn's largest moon, Titan. Even though the spacecraft will be at 73,974 miles (119,049 kilometers) away, the gravitational influence of the moon will slow down the spacecraft slightly as it speeds past. A few days later, instead of passing through the outermost fringes of Saturn's atmosphere, Cassini will dive in too deep to survive the friction and heating.

September 14 -- Cassini's imaging cameras take their last look around the Saturn system, sending back pictures of moons Titan and Enceladus, the hexagon-shaped jet stream around the planet's north pole, and features in the rings.

September 14 (5:45 p.m. EDT / 2:45 p.m. PDT) -- Cassini turns its antenna to point at Earth, begins a communications link that will continue until end of mission, and sends back its final images and other data collected along the way.

September 15 (4:37 a.m. EDT / 1:37 a.m. PDT) -- The "final plunge" begins. The spacecraft starts a 5-minute roll to position INMS for optimal sampling of the atmosphere, transmitting data in near real time from this point to end of mission.

September 15 (7:53 a.m. EDT / 4:53 a.m. PDT) -- Cassini enters Saturn's atmosphere. Its thrusters fire at 10 percent of their capacity to maintain directional stability, enabling the spacecraft's high-gain antenna to remain pointed at Earth and allowing continued transmission of data.

September 15 (7:54 a.m. EDT / 4:54 a.m. PDT) -- Cassini's thrusters are at 100 percent of capacity. Atmospheric forces overwhelm the thrusters' capacity to maintain control of the spacecraft's orientation, and the high-gain antenna loses its lock on Earth. At this moment, expected to occur about 940 miles (1,510 kilometers) above Saturn's cloud tops, communication from the spacecraft will cease, and Cassini's mission of exploration will have concluded. The spacecraft will break up like a meteor moments later.

A Very Long Mission at Saturn

As Cassini completes its 13-year tour of Saturn, its Grand Finale -- which began in April -- and final plunge are just the last beat. Following a four-year primary mission and a two-year extension, NASA approved an ambitious plan to extend Cassini's service by an additional seven years. Called the Cassini Solstice Mission, the extension saw Cassini perform dozens more flybys of Saturn's moons as the spacecraft observed seasonal changes in the atmospheres of Saturn and Titan. From the outset, the planned endgame for the Solstice Mission was to expend all of Cassini's maneuvering propellant exploring, then eventually arriving in the ultra-close Grand Finale orbits, ending with safe disposal of the spacecraft in Saturn's atmosphere.

Mountains of New Data on the Saturn System

Since its launch in 1997, the findings of the Cassini mission have revolutionized our understanding of Saturn, its complex rings, the amazing assortment of moons and the planet's dynamic magnetic environment. The most distant planetary orbiter ever launched, Cassini started making astonishing discoveries immediately upon arrival and continues today. Icy jets shoot from the tiny moon Enceladus, providing samples of an underground ocean with evidence of hydrothermal activity. Titan's hydrocarbon lakes and seas are dominated by liquid ethane and methane, and complex pre-biotic chemicals form in the atmosphere and rain to the surface. Three-dimensional structures tower above Saturn's rings, and a giant Saturn storm circled the entire planet for most of a year. Cassini's findings at Saturn have also buttressed scientists' understanding of processes involved in the formation of planets.

Why End the Mission?

The spacecraft is running low on the rocket fuel used for adjusting its course. If left unchecked, this situation would eventually prevent mission operators from controlling the course of the spacecraft.

Two moons of Saturn, Enceladus and Titan, have captured news headlines over the past decade as Cassini data revealed their potential to contain habitable – or at least "prebiotic” – environments.

In order to avoid the unlikely possibility of Cassini someday colliding with one of these moons, NASA chose to safely dispose of the spacecraft in the atmosphere of Saturn. This will ensure that Cassini cannot contaminate any future studies of habitability and potential life on Enceladus and Titan.

For more information about the Saturn system and the Cassini mission, click on the links below.

NASA Cassini Mission

NASA Saturn/Cassini Mission Coverage

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Asteroid 3122 Florence Close Approach September 1

On September 1, asteroid 3122 Florence will become the largest asteroid to fly by Earth since near-Earth asteroids were discovered a century ago.

Asteroid 3122 Florence will pass by Earth on September 1, 2017, at a distance of about 4.4 million miles. Image Credit: NASA/JPL-Caltech

Measurements made by the Spitzer Space Telescope and NEOWISE asteroid-hunting instrument suggest that Florence is around 2.7 miles (5 km) in diameter. The asteroid will pass 4.4 million miles from Earth, about 18 times the distance from the Earth to the moon.

Many known asteroids have passed closer to Earth than Florence will, but those were estimated to be smaller. NASA has tracked near-Earth objects since 1998.

Background on Florence

The body called Florence was first detected March 2, 1981 by American astronomer Schelte “Bobby” Bus from Australia’s Siding Spring Observatory. The discovery was provisionally labeled 1981 ET₃. In 1993, it was acknowledged as asteroid discovery number 3122 and was named 3122 Florence in honor of Florence Nightingale (1820-1910), the founder of modern nursing.

3122 Florence is a stony asteroid of the Amor group, classified as near-Earth object and potentially hazardous asteroid (PAH). It orbits the sun at a distance of 1.0–2.5 AU once every 2 years and 4 months (859 days). Its orbit has an eccentricity of 0.42 and an inclination of 22° with respect to the ecliptic. The PHA classification is due to both the body’s absolute magnitude (H ≤ 22) and its minimum orbit intersection distance (MOID ≤ 0.05 AU).

Observing Opportunity

For visual astronomers, 3122 Florence will be clearly visible in the night sky beginning August 27. On September 1, 3122 Florence will pass 0.04723 AU (7,066,000 km; 4,390,000 mi) from Earth, brightening to apparent magnitude 8.5, when it will be visible in small telescopes for several nights as it moves through the constellations Piscis Austrinus, Capricornus, Aquarius and Delphinus.

NEO Close Approaches in 2017

Florence is just one of a few bodies passing Earth this year. In January, asteroid 2017 AG₁₃ snuck up on astronomers. The body was between 36 and 111 feet wide and passed Earth at half the distance to the moon. Another asteroid in the same size range, 2012 TC₄, is scheduled to pass roughly one-fourth the distance to the moon—between 4,200 miles and 170,000 miles—on October 12, 2017.

Earth-Based Radar Observing

The size and proximity of Florence make it a perfect target for ground-based radio telescope observations. Radar imaging is planned at NASA's Goldstone Solar System Radar in California and at the National Science Foundation's Arecibo Observatory in Puerto Rico. The resulting radar images will show the real size of Florence and could reveal surface details as small as about 30 feet (10 meters).

NEO Tracking Continues

Currently, NASA is tracking 1,826 near-Earth objects classified as Potentially Hazardous Asteroids, which have some risk of striking Earth in the future. Among those are several larger than Florence, including 1999 JM₈ at 4.3 miles across, 4183 Cuno at 3.5 miles across and 3200 Phaeton at 3.2 miles across. None have come as close as Florence. Florence won’t make a closer pass until around the year 2500.

More information about asteroids and near-Earth objects can be found at:

NASA Center for Near Earth Object Studies

NASA Asteroid Watch

For more information about NASA's Planetary Defense Coordination Office, visit:

NASA Planeterary Defense Coordination Office

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