Planetary and Asteroid Studies

What’s Up – October 2019

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Published by NASA

moonjournal_main
Celebrate International Observe the Moon Night with NASA on October 5! Credit: NASA/JPL

 

Link to article with video: https://www.jpl.nasa.gov/video/details.php?id=1588

Link to page: International Observe the Moon Night, Oct 5, 2019

What can you see in the October sky? Join the global celebration of International Observe the Moon Night on Oct. 5th, then try to catch the ice giant planets Uranus and Neptune, which are well placed for viewing in the late night sky.

Transcript:

What’s Up for October? A night for the whole world to observe the Moon and hunting for ice giants!

International Observe the Moon Night is Oct. 5th. It’s an annual celebration of lunar observation and exploration. Events are scheduled in lots of places around the world, so there may be one near you. But all you really need to participate is to go out and look up.

The event is timed to coincide with the first quarter moon. This allows for some great observing along the lunar terminator – the line that divides the dayside from the nightside. With even a small pair of binoculars, you can see some great details as features like mountains and craters pop up into the light. Learn more and look for events in your area at moon.nasa.gov/observe.

October is a great time to try and capture an ICE GIANT. Now, these aren’t mythical creatures. They’re planets – the most distant of the major planets of our solar system, Uranus and Neptune.

The four giant planets of our solar system are not created equal. The gas giants, Jupiter and Saturn, are much bigger and way more massive, while the ice giants are so named because they contain a much higher amount of materials that typically form ices in the frigid depths of the outer solar system.

In October, both Uranus and Neptune are well placed in the late night sky. In fact, you can see all four giant planets in the same evening if you look for Jupiter and Saturn in the west after sunset, and then come back a couple of hours later to spot Uranus and Neptune. (Think of it as your own personal “Voyager mission.” NASA’s Voyager 2 is the only spacecraft to have visited the ice giants so far, although scientists are eager to go back for a more detailed study.)

Unlike Jupiter and Saturn, the ice giants are quite faint, so the best way to observe them is with a telescope, and from personal experience, it’s much easier to find them if you have a computer-controlled mount that can automatically point the telescope for you. If you don’t have access to one, find a local event with the Night Sky Network at nightsky.jpl.nasa.gov. Otherwise, sky watching apps can help you star-hop your way to these two incredibly distant planets.

Now be advised, because they’re so far away, each planet appears as just a point of light. But with a modest telescope, you’ll see Uranus as a tiny disk. You’d be forgiven for mistaking Neptune as a star – it’s the same size as Uranus, but much farther away, so it’s fainter.

The ice giants are elusive, but well worth the effort to say you’ve seen them with your own eyes.

Here are the phases of the Moon for October. You can catch up on all of NASA’s current and future missions at nasa.gov. I’m Preston Dyches from NASA’s Jet Propulsion Laboratory, and that’s What’s Up for this month.

 

New Organic Compounds Found in Enceladus Ice Grains

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Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
gretchen.p.mccartney@jpl.nasa.gov

Alana Johnson
NASA Headquarters, Washington
alana.r.johnson@nasa.gov

PIA09761_hires
In this image captured by NASA’s Cassini spacecraft in 2007, the plumes of Enceladus are clearly visible. The moon is nearly in front of the Sun from Cassini’s viewpoint.Credit: NASA/JPL/Space Science Institute

New kinds of organic compounds, the ingredients of amino acids, have been detected in the plumes bursting from Saturn’s moon Enceladus. The findings are the result of the ongoing deep dive into data from NASA’s Cassini mission.

Powerful hydrothermal vents eject material from Enceladus’ core, which mixes with water from the moon’s massive subsurface ocean before it is released into space as water vapor and ice grains. The newly discovered molecules, condensed onto the ice grains, were determined to be nitrogen- and oxygen-bearing compounds.

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Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif.
gretchen.p.mccartney@jpl.nasa.gov

Alana Johnson
NASA Headquarters, Washington
alana.r.johnson@nasa.gov

PIA09761_hires
In this image captured by NASA’s Cassini spacecraft in 2007, the plumes of Enceladus are clearly visible. The moon is nearly in front of the Sun from Cassini’s viewpoint.Credit: NASA/JPL/Space Science Institute

New kinds of organic compounds, the ingredients of amino acids, have been detected in the plumes bursting from Saturn’s moon Enceladus. The findings are the result of the ongoing deep dive into data from NASA’s Cassini mission.

Powerful hydrothermal vents eject material from Enceladus’ core, which mixes with water from the moon’s massive subsurface ocean before it is released into space as water vapor and ice grains. The newly discovered molecules, condensed onto the ice grains, were determined to be nitrogen- and oxygen-bearing compounds.

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Scientists Finally Know What Time It Is on Saturn

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Gretchen McCartney
Jet Propulsion Laboratory, Pasadena, Calif. 

JoAnna Wendel 
NASA Headquarters, Washington DC

 

A view from NASA’s Cassini spacecraft shows Saturn’s northern hemisphere in 2016 as that part of the planet nears its northern hemisphere summer solstice. A year on Saturn is 29 Earth years; days only last 10:33:38, according to a new analysis of Cassini data. Credit: NASA/JPL-Caltech/Space Science Institute

 

Using new data from NASA’s Cassini spacecraft, researchers believe they have solved a longstanding mystery of solar system science: the length of a day on Saturn. It’s 10 hours, 33 minutes and 38 seconds. 

The figure has eluded planetary scientists for decades, because the gas giant has no solid surface with landmarks to track as it rotates, and it has an unusual magnetic field that hides the planet’s rotation rate.

The answer, it turned out, was hidden in the rings. 

 

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What Uranus Cloud Tops Have in Common With Rotten Eggs

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Uranus
Arriving at Uranus in 1986, Voyager 2 observed a bluish orb with extremely subtle features. A haze layer hid most of the planet’s cloud features from view. Credit: NASA/JPL-Caltech

  

Even after decades of observations and a visit by NASA’s Voyager 2 spacecraft, Uranus held on to one critical secret — the composition of its clouds. Now, one of the key components of the planet’s clouds has finally been verified. 

A global research team that includes Glenn Orton of NASA’s Jet Propulsion Laboratory in Pasadena, California, has spectroscopically dissected the infrared light from Uranus captured by the 26.25-foot (8-meter) Gemini North telescope on Hawaii’s Mauna Kea. They found hydrogen sulfide, the odiferous gas that most people avoid, in Uranus’ cloud tops. The long-sought evidence was published in the April 23rd issue of the journal Nature Astronomy.

The detection of hydrogen sulfide high in Uranus’ cloud deck (and presumably Neptune’s) is a striking difference from the gas giant planets located closer to the Sun — Jupiter and Saturn — where ammonia is observed above the clouds, but no hydrogen sulfide. These differences in atmospheric composition shed light on questions about the planets’ formation and history. 

 
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NASA’s Juno Spacecraft Set for Fifth Jupiter Flyby

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DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington

 

This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian “galaxy” of swirling storms. Credits: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

 

NASA’s Juno spacecraft will make its fifth flyby over Jupiter’s mysterious cloud tops on Monday, March 27, at 1:52 a.m. PDT (4:52 a.m. EDT, 8:52 UTC).

At the time of closest approach (called perijove), Juno will be about 2,700 miles (4,400 kilometers) above the planet’s cloud tops, traveling at a speed of about 129,000 miles per hour (57.8 kilometers per second) relative to the gas-giant planet. All of Juno’s eight science instruments will be on and collecting data during the flyby.


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NASA Scientists Find ‘Impossible’ Cloud on Titan — Again

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The hazy globe of Titan hangs in front of Saturn and its rings in this natural color view from NASA’s Cassini spacecraft. Image credit: NASA/JPL-Caltech/Space Science Institute

 

The puzzling appearance of an ice cloud seemingly out of thin air has prompted NASA scientists to suggest that a different process than previously thought — possibly similar to one seen over Earth’s poles — could be forming clouds on Saturn’s moon Titan.

Located in Titan’s stratosphere, the cloud is made of a compound of carbon and nitrogen known as dicyanoacetylene (C4N2), an ingredient in the chemical cocktail that colors the giant moon’s hazy, brownish-orange atmosphere. 

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A Mixed-reality Trip to Mars

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A ceremonial ribbon is cut for the opening of new “Destination: Mars” experience at the Kennedy Space Center visitor complex in Florida. From the left are Therrin Protze, chief operating officer of the visitor complex; center director Bob Cabana; Apollo 11 astronaut Buzz Aldrin; Kudo Tsunoda of Microsoft; and Jeff Norris of NASA’s Jet Propulsion Laboratory in Pasadena, California. Photo credit: NASA/Charles Babir

 

It’ll be years before the first astronauts leave the launch pad on Earth to journey to Mars. But starting Sept. 19, visitors to the Kennedy Space Center visitor complex in Florida will get a taste of what those astronauts will see when they touch down on the Red Planet.

“Destination: Mars,” a mixed-reality experience designed by NASA’s Jet Propulsion Laboratory, Pasadena, California, and Microsoft HoloLens, held a kick-off event for media at the Visitor Complex on Sept. 18. The experience uses real imagery taken by NASA’s Mars Curiosity rover to let users explore the Martian surface.

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NASA Prepares to Launch First U.S. Asteroid Sample Return Mission

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OSIRIS-REx will travel to near-Earth asteroid Benn on a sample return mission Credits: NASA

  

NASA is preparing to launch its first mission to return a sample of an asteroid to Earth. The mission will help scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth.

The Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft will travel to the near-Earth asteroid Bennu and bring a sample back to Earth for intensive study. Launch is scheduled for 7:05 p.m. EDT Thursday, Sept. 8 from Cape Canaveral Air Force Station in Florida. 

“This mission exemplifies our nation’s quest to boldly go and study our solar system and beyond to better understand the universe and our place in it,” said Geoff Yoder, acting associate administrator for the agency’s Science Mission Directorate in Washington. “NASA science is the greatest engine of scientific discovery on the planet and OSIRIS-REx embodies our directorate’s goal to innovate, explore, discover, and inspire.” 

The 4,650-pound (2,110-kilogram) fully-fueled spacecraft will launch aboard an Atlas V 411 rocket during a 34-day launch period that begins Sept. 8, and reach its asteroid target in 2018. After a careful survey of Bennu to characterize the asteroid and locate the most promising sample sites, OSIRIS-REx will collect between 2 and 70 ounces (about 60 to 2,000 grams) of surface material with its robotic arm and return the sample to Earth via a detachable capsule in 2023.

“The launch of OSIRIS-REx is the beginning a seven-year journey to return pristine samples from asteroid Bennu,” said OSIRIS-REx Principal Investigator Dante Lauretta of the University of Arizona, Tucson. “The team has built an amazing spacecraft, and we are well-equipped to investigate Bennu and return with our scientific treasure.” 

OSIRIS-REx has five instruments to explore Bennu:

  • OSIRIS-REx Camera Suite (OCAMS) – A system consisting of three cameras provided by the University of Arizona, Tucson, will observe Bennu and provide global imaging, sample site imaging, and will witness the sampling event.
  • OSIRIS-REx Laser Altimeter (OLA) – A scanning LIDAR (Light Detection and Ranging) contributed by the Canadian Space Agency will be used to measure the distance between the spacecraft and Bennu’s surface, and will map the shape of the asteroid.
  • OSIRIS-REx Thermal Emission Spectrometer (OTES) – An instrument provided by Arizona State University in Tempe that will investigate mineral abundances and provide temperature information with observations in the thermal infrared spectrum.
  • OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) – An instrument provided by NASA’s Goddard Space Flight Center in Greenbelt, Maryland and designed to measure visible and infrared light from Bennu to identify mineral and organic material.
  • Regolith X-ray Imaging Spectrometer (REXIS) – A student experiment provided by the Massachusetts Institute of Technology (MIT) and Harvard University in Cambridge, which will observe the X-ray spectrum to identify chemical elements on Bennu’s surface and their abundances.

Additionally, the spacecraft has two systems that will enable the sample collection and return:

  • Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – An articulated robotic arm with a sampler head, provided by Lockheed Martin Space Systems in Denver, to collect a sample of Bennu’s surface.
  • OSIRIS-REx Sample Return Capsule (SRC) – A capsule with a heat shield and parachutes in which the spacecraft will return the asteroid sample to Earth, provided by Lockheed Martin. 

“Our upcoming launch is the culmination of a tremendous amount of effort from an extremely dedicated team of scientists, engineers, technicians, finance and support personnel,” said OSIRIS-REx Project Manager Mike Donnelly at Goddard. “I’m incredibly proud of this team and look forward to launching the mission’s journey to Bennu and back.”

Goddard provides overall mission management, systems engineering, and safety and mission assurance for OSIRIS-REx. Lockheed Martin Space Systems built the spacecraft. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator. OSIRIS-REx is the third mission in NASA’s New Frontiers Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages New Frontiers for the agency’s Science Mission Directorate in Washington.

For images, video, and more information, visit: http://www.nasa.gov/osiris-rex and http://www.asteroidmission.org

NASA’s Juno Spacecraft in Orbit Around Mighty Jupiter

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The Juno team celebrates at NASA’s Jet Propulsion Laboratory in Pasadena, California, after receiving data indicating that NASA’s Juno mission entered orbit around Jupiter. Rick Nybakken, Juno project manager at JPL, is seen at the center hugging JPL’s acting director for solar system exploration, Richard Cook. Image Credit: NASA/JPL-Caltech

 

Note from George McGinn: Yesterday I watched NASA’s briefing, and the Juno Spacecraft did something nearly impossible. The largest danger to the mission is the immense radiation. Jupiter’s version of Earth’s Van Allen belt have been catching huge amounts of solar radiation for 4.5 billion years. The gravity of Jupiter is so strong that it pulls more charged particles than would directly hit it. The Juno team estimated that the spacecraft will be exposed to radiation at LD25 (LD is Leathal Dose and 25 means 25 times, so 25 times the lethal dose to a human), or having 1 million dental X-rays all at once (in a space of 2 seconds). This is equal to 260 rads.

I applaud the Juno’s team, who worked almost 12 years to get this spacecraft safely in orbit. I am excited to see finally how deep the atmosphere goes, what gases make up Jupiter, and if there is a solid or semi-solid center, or just compressed gases. And can all that gas create the large magnetic field, or what is in the center, the speed of spin, and the chemical makeup. 

 

After an almost five-year journey to the solar system’s largest planet, NASA’s Juno spacecraft successfully entered Jupiter’s orbit during a 35-minute engine burn. Confirmation that the burn had completed was received on Earth at 8:53 pm. PDT (11:53 p.m. EDT) Monday, July 4.

“Independence Day always is something to celebrate, but today we can add to America’s birthday another reason to cheer — Juno is at Jupiter,” said NASA Administrator Charlie Bolden. “And what is more American than a NASA mission going boldly where no spacecraft has gone before? With Juno, we will investigate the unknowns of Jupiter’s massive radiation belts to delve deep into not only the planet’s interior, but into how Jupiter was born and how our entire solar system evolved.” 

Confirmation of a successful orbit insertion was received from Juno tracking data monitored at the navigation facility at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, as well as at the Lockheed Martin Juno operations center in Denver. The telemetry and tracking data were received by NASA’s Deep Space Network antennas in Goldstone, California, and Canberra, Australia.

“This is the one time I don’t mind being stuck in a windowless room on the night of the Fourth of July,” said Scott Bolton, principal investigator of Juno from Southwest Research Institute in San Antonio. “The mission team did great. The spacecraft did great. We are looking great. It’s a great day.”

Preplanned events leading up to the orbital insertion engine burn included changing the spacecraft’s attitude to point the main engine in the desired direction and then increasing the spacecraft’s rotation rate from 2 to 5 revolutions per minute (RPM) to help stabilize it..

The burn of Juno’s 645-Newton Leros-1b main engine began on time at 8:18 p.m. PDT (11:18 p.m. EDT), decreasing the spacecraft’s velocity by 1,212 mph (542 meters per second) and allowing Juno to be captured in orbit around Jupiter. Soon after the burn was completed, Juno turned so that the sun’s rays could once again reach the 18,698 individual solar cells that give Juno its energy.

“The spacecraft worked perfectly, which is always nice when you’re driving a vehicle with 1.7 billion miles on the odometer,” said Rick Nybakken, Juno project manager from JPL. “Jupiter orbit insertion was a big step and the most challenging remaining in our mission plan, but there are others that have to occur before we can give the science team members the mission they are looking for.”

 

This is the final view taken by the JunoCam instrument on NASA’s Juno spacecraft before Juno’s instruments were powered down in preparation for orbit insertion. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter. Image Credit: NASA/JPL-Caltech (Click image for full-size)


Over the next few months, Juno’s mission and science teams will perform final testing on the spacecraft’s subsystems, final calibration of science instruments and some science collection.

“Our official science collection phase begins in October, but we’ve figured out a way to collect data a lot earlier than that,” said Bolton. “Which when you’re talking about the single biggest planetary body in the solar system is a really good thing. There is a lot to see and do here.” 

Juno’s principal goal is to understand the origin and evolution of Jupiter. With its suite of nine science instruments, Juno will investigate the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras. The mission also will let us take a giant step forward in our understanding of how giant planets form and the role these titans played in putting together the rest of the solar system. As our primary example of a giant planet, Jupiter also can provide critical knowledge for understanding the planetary systems being discovered around other stars. 

The Juno spacecraft launched on Aug. 5, 2011, from Cape Canaveral Air Force Station in Florida. JPL manages the Juno mission for NASA. Juno is part of NASA’s New Frontiers Program, managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate. Lockheed Martin Space Systems in Denver built the spacecraft. The California Institute of Technology in Pasadena manages JPL for NASA.

More information on the Juno mission is available at: http://www.nasa.gov/juno

Follow the mission on Facebook and Twitter at: http://www.facebook.com/NASAJuno or http://www.twitter.com/NASAJuno

Gluttonous Star May Hold Clues to Planet Formation

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The brightness of outbursting star FU Orionis has been slowly fading since its initial flare-up in 1936. Researchers found that it has dimmed by about 13 percent in short infrared wavelengths from 2004 (left) to 2016 (right). Credit: NASA/JPL-Caltech

 

In 1936, the young star FU Orionis began gobbling material from its surrounding disk of gas and dust with a sudden voraciousness. During a three-month binge, as matter turned into energy, the star became 100 times brighter, heating the disk around it to temperatures of up to 12,000 degrees Fahrenheit (7,000 Kelvin). FU Orionis is still devouring gas to this day, although not as quickly. 

This brightening is the most extreme event of its kind that has been confirmed around a star the size of the sun, and may have implications for how stars and planets form. The intense baking of the star’s surrounding disk likely changed its chemistry, permanently altering material that could one day turn into planets.  

“By studying FU Orionis, we’re seeing the absolute baby years of a solar system,” said Joel Green, a project scientist at the Space Telescope Science Institute, Baltimore, Maryland. “Our own sun may have gone through a similar brightening, which would have been a crucial step in the formation of Earth and other planets in our solar system.”

Visible light observations of FU Orionis, which is about 1,500 light-years away from Earth in the constellation Orion, have shown astronomers that the star’s extreme brightness began slowly fading after its initial 1936 burst. But Green and colleagues wanted to know more about the relationship between the star and surrounding disk. Is the star still gorging on it? Is its composition changing? When will the star’s brightness return to pre-outburst levels?  

To answer these questions, scientists needed to observe the star’s brightness at infrared wavelengths, which are longer than the human eye can see and provide temperature measurements.  

Green and his team compared infrared data obtained in 2016 using the Stratospheric Observatory for Infrared Astronomy, SOFIA, to observations made with NASA’s Spitzer Space Telescope in 2004. SOFIA, the world’s largest airborne observatory, is jointly operated by NASA and the German Aerospace Center and provides observations at wavelengths no longer attainable by Spitzer. The SOFIA data were taken using the FORCAST instrument (Faint Object infrared Camera for the SOFIA Telescope). 

“By combining data from the two telescopes collected over a 12-year interval, we were able to gain a unique perspective on the star’s behavior over time,” Green said. He presented the results at the American Astronomical Society meeting in San Diego, this week. 

Using these infrared observations and other historical data, researchers found that FU Orionis had continued its ravenous snacking after the initial brightening event: The star has eaten the equivalent of 18 Jupiters in the last 80 years.

The recent measurements provided by SOFIA inform researchers that the total amount of visible and infrared light energy coming out of the FU Orionis system decreased by about 13 percent over the 12 years since the Spitzer observations. Researchers determined that this decrease is caused by dimming of the star at short infrared wavelengths, but not at longer wavelengths. That means up to 13 percent of the hottest material of the disk has disappeared, while colder material has stayed intact.    

“A decrease in the hottest gas means that the star is eating the innermost part of the disk, but the rest of the disk has essentially not changed in the last 12 years,” Green said. “This result is consistent with computer models, but for the first time we are able to confirm the theory with observations.” 

Astronomers predict, partly based on the new results, that FU Orionis will run out of hot material to nosh on within the next few hundred years. At that point, the star will return to the state it was in before the dramatic 1936 brightening event. Scientists are unsure what the star was like before or what set off the feeding frenzy.

“The material falling into the star is like water from a hose that’s slowly being pinched off,” Green said. “Eventually the water will stop.” 

If our sun had a brightening event like FU Orionis did in 1936, this could explain why certain elements are more abundant on Mars than on Earth. A sudden 100-fold brightening would have altered the chemical composition of material close to the star, but not as much farther from it. Because Mars formed farther from the sun, its component material would not have been heated up as much as Earth’s was. 

At a few hundred thousand years old, FU Orionis is a toddler in the typical lifespan of a star. The 80 years of brightening and fading since 1936 represent only a tiny fraction of the star’s life so far, but these changes happened to occur at a time when astronomers could observe. 

“It’s amazing that an entire protoplanetary disk can change on such a short timescale, within a human lifetime,” said Luisa Rebull, study co-author and research scientist at the Infrared Processing and Analysis Center (IPAC), based at Caltech, Pasadena, California.   

Green plans to gain more insight into the FU Orionis feeding phenomenon with NASA’s James Webb Space Telescope, which will launch in 2018. SOFIA has mid-infrared high-resolution spectrometers and far-infrared science instrumentation that complement Webb’s planned near- and mid-infrared capabilities. Spitzer is expected to continue exploring the universe in infrared light, and enabling groundbreaking scientific investigations, into early 2019. 

NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Spitzer Space Telescope mission for NASA. Science operations are conducted at the Spitzer Science Center at Caltech. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA. 

SOFIA is a joint project of NASA and the German Aerospace Center (DLR). The aircraft is based at NASA Armstrong Flight Research Center’s facility in Palmdale, California. NASA’s Ames Research Center in Moffett Field, California, manages the SOFIA science and mission operations in cooperation with the Universities Space Research Association (USRA) headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. 

For more information about Spitzer, visit: http://www.nasa.gov/ or http://spitzer.caltech.edu

For more information about SOFIA, visit: http://www.nasa.gov/sofia or http://www.dlr.de/en/sofia