NASA Selects New Projects to Study Mars and Mercury

ExoMars Rover. Credit: ESA Click for larger version

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Making good on its promise to work together with other space agencies, NASA has selected two science instruments that will fly on board European Space Agency (ESA) spacecraft, one heading to Mars on the ExoMars rover, the other to Mercury with the BepiColombo orbiter. “The selections will further advance our knowledge of these exciting terrestrial planets,” said Jim Green, director of NASA’s Planetary Division at NASA Headquarters in Washington. “The international collaboration will create a new chapter in planetary science and provide a strong partnership with the international science community to complement future robotic and human exploration activities.”

The Lander Radio-Science on ExoMars, or LaRa, will use NASA’s Deep Space Network of radio telescopes to track part of ESA’s ExoMars mission. Scheduled to launch in 2016, the mission consists of a fixed lander and a rover that will roam Mars collecting soil samples for detailed analysis.

Data relayed from the lander back to the network will allow scientists to measure and analyze variations in the length of the day and location of the planet’s rotational axis. This data will help researchers further dissect the structure of the Red Planet’s interior, including the size of its core. When combined with the lander’s onboard instruments, the data also may help confirm whether the planet’s interior is still, at least partially, composed of liquid. William Folkner of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., is the principal investigator. The project costs approximately $6.6 million.

BepiColombo - Mission to Mercury.  Credit: ESA  Click for larger version.
BepiColombo - Mission to Mercury. Credit: ESA Click for larger version.

The second science instrument selection, named Strofio, will employ a unique mass spectrometer on board the BepiColombo mission. The instrument will determine the mass of atoms and molecules to reveal the composition of Mercury’s atmosphere. The investigation will study the atmosphere, which is formed from material ejected from its surface, to reveal the composition of Mercury’s surface.

Strofio will be a component of the Italian Space Agency’s suite of science instruments that will fly aboard BepiColombo . Scheduled for launch in 2013, the mission is composed of two spacecraft. Japan will build one spacecraft to study the planet’s magnetic field. ESA will build the other to study Mercury directly. Stefano Livi of the Southwest Research Institute in San Antonio is the principal investigator. The project costs approximately $31.8 million.

The selections were chosen from eight proposals submitted in December 2008 in response to NASA’s new Stand Alone Mission of Opportunity, known as Salmon. NASA solicited proposals for investigations that address planetary science research objectives on non-agency missions. A key criterion is that science goals, including data archiving and analysis, must be accomplished for less than $35 million.

Source: NASA

Hubble Servicing Mission Meets the Big Screen; Watch With Friends

Previous Hubble servicing mission. Credit: NASA

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The crew of the upcoming Hubble servicing mission have not only been busy training for all contingencies of spaceflight on the shuttle and telescope repair (have you been following Astro_Mike on Twitter?) but they’ve also been training for the big screen. The REALLY big screen. NASA announced today that the crew will be using IMAX 3-D cameras to document this most complex of space shuttle operations — the final servicing mission to the Hubble Space Telescope. And in another bit of news, in a show of solidarity and support of the shuttle astronauts, astronomers from the University of Alabama are encouraging everyone to “raise a wing” to the Hubble repair crew.

The IMAX 3-D cameras will launch aboard space shuttle Atlantis, which is scheduled to lift off May 11. Astronauts will use the cameras to film five spacewalks needed to repair and upgrade Hubble. The IMAX footage will be combined with images from Hubble itself to create a new IMAX producton, “Hubble 3D,” set for release in spring 2010.

“We have worked with IMAX on past Hubble missions and are excited about working with them again on the current Hubble mission. The Hubble Space Telescope continues to dazzle us with the splendor of our universe, and after the mission we look forward to many more years of awe-inspiring imagery,” said Bob Jacobs, NASA’s acting assistant administrator for public affairs at NASA Headquarters in Washington. “IMAX has developed innovative 3-D image capture and projection technology that creates a large-scale, immersive educational experience in which those of us on the ground are no longer passive observers of spaceflight, we’re active participants.”

The IMAX team has trained Atlantis’ crew at NASA’s Johnson Space Center in Houston to operate the cameras. One will be mounted outside the crew cabin in the shuttle’s cargo bay to capture IMAX 3-D images of the historic final servicing mission. The commander and pilot will double as filmmakers as two teams of spacewalking astronauts — working in tandem with the shuttle’s robotic arm — perform some of the most challenging work ever undertaken in space as they replace and refurbish many of the telescope’s precision instruments.

And now for more on “raising a wing” to the crew, which came to us via Pamela Gay: Dr. William Keel of the University of Alabama Department of Physics and Astronomy is planning to head to the local Buffalo Wild Wings to watch NASA TV during the Hubble repair mission’s EVAs. This is perhaps astronomy’s “championship” event, and instead of the Final Four, it’s the final Hubble servicing mission. Keel will be watching with colleagues and students to take in the EVAs and perhaps even raise a Wild Wing in salute of the astronauts achievements.

On her Starstryder blog, Gay says, “While this idea started in Tuscaloosa, there is no reason for it to end there. Many restaurants and bars have cable television packages that include NASA TV. Next week, grab a friend and grab a beverage and ask the guy behind the bar to tune the TV into the greatest high risk game of all: It’s Man versus the Machine as Mike Massimino and the STS-125 team of astronauts upgrade the Hubble Space Telescope.”

If you’re interested in joining in, check out the NASA TV schedule.

The Spitzer Space Telescope Speaks Its Mind

An interview with the Spitzer Space Telescope. Credit: NASA/JPL

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The Spitzer Space Telescope is close to running out of coolant. Around May 12, the telescope will use up the last drop of the coolant that chills the instruments to just a few degrees above absolute zero. Everyone knew this was coming, but still it is sobering news. However, even though the coolant will be depleted, Spitzer will remain cold enough to still probe the universe with its infrared detectors for at least a couple of years. But we all like to think these missions will go on forever, at least I do anyway. The Jet Propulsion Laboratory shared this news in one of the more creative press releases ever put out by any NASA center: they interviewed the telescope. That’s right, the telescope. Not the principal investigator, not the chief engineer, but the telescope itself.

The spacecraft, which is now in orbit around the sun more than 100-million kilometers (62-million miles) behind Earth, will heat up just a bit — its instruments will warm up from – 456 degrees Fahrenheit (-271 Celsius) to – 404 degrees Fahrenheit (-242 Celsius).

If Spitzer could talk, here’s what the telescope might say:

Interviewer: It’s cold in here.

Spitzer: Sorry. Even though I’m warming up, I still need to be quite chilly for two of my infrared channels to continue working.

Interviewer: Why do infrared telescopes need to be cold?

Spitzer: Good question. Infrared light is produced by heat. So, engineers reduce my own heat to make sure that I’m measuring just the infrared light from the objects I’m studying. This is the same reason why I circle around the sun, far behind Earth, and why I have big sun shields — to keep cool.

Interviewer: Tell me, Spitzer, about what you consider to be your greatest discovery?

Spitzer: Probably my work on exoplanets, which are planets that orbit stars other than our sun. I hate to brag, but I was the first telescope to see actual light from an exoplanet. I was also the first to split that light up into a spectrum. Oh, sorry, there I go again with the techie talk. Light is made up of lots of different wavelengths in the same way that a rainbow is made up of different colors. I was able to split an exoplanet’s light up into its various infrared wavelengths. This spectral information teaches us about planets’ atmospheres.

Interviewer: What did you learn about the planets?

Spitzer: For one thing, I learned that the hot gas exoplanets, called “hot Jupiters,” are not all alike. Some are wild, with temperatures as hot as fire and almost as cold as ice. Others are more even-keeled. I also created the first temperature map of an exoplanet, and watched a storm of colossal proportions brewing across the face of one bizarre exoplanet – it has an orbit that swings in really close to its star and then back out to about where Earth sits in our solar system.

Interviewer: You seem to really like planets.

Spitzer: Well, you know, I wasn’t even originally designed to see exoplanets! It was a complete surprise to me that I had this amazing ability. I can tell you that I do, and always will, have a thing for planetary disks. Because I have infrared eyes, I can see the warm and dusty planetary materials that swirl in disks around young stars. I can also see older disks littered with the remnants of planets. In fact, I’ve probably looked at thousands of disks so far. What’s been fun is finding them around all sorts of oddball stars, such as those that are dead, doubled up as twins and even as small as planets. Bottom line is that the process of growing planets seems to happen quite easily all over the galaxy, and perhaps the universe.

Interviewer: Does that mean aliens could be everywhere?

Spitzer: I can’t really give you a good answer for that. Yes, the studies of disks are showing us that rocky planets are common, but we don’t know if the planets could have life. Also, keep in mind that, as of now, nobody has detected any planets that are just like Earth. These would be rocky worlds around stars like our sun that have the right temperature for lakes and oceans. That job will most likely fall to NASA’s Kepler mission, which will begin hunting for them soon.

Interviewer: Did you look at other objects besides disks and planets?

Spitzer: Oh yes, certainly. I have looked at comets in our solar system, the farthest galaxies known, and everything in-between. I was really excited to find hundreds of hidden black holes billions of light-years away. Astronomers had known they were there because they shoot X-rays into space that can be detected as a diffuse glow. But the objects themselves were choked in dust. My infrared eyes, unlike your human eyes, can see through dust, so I was able to round up a lot of these missing black holes.

Interviewer: Is there any other discovery you want to mention?

Spitzer: There are too many to list, but I am particularly proud of this huge mosaic I took of a large swath of our Milky Way galaxy. It looks stunning when you print it out to poster size, and it’s the best view ever of the bustling central portion of our galaxy. You see, the middle of the Milky Way is hopping with stars and dust. It’s chaos, and visible-light cannot escape. These observations not only look cool, they also helped astronomers remap the structure of our galaxy. The new map shows just two spiral arms of stars instead of four as previously believed. How crazy is that!

Interviewer: So what lies ahead?

Spitzer: Well, I’m really looking forward to the warm mission, because now that I have just two infrared channels working, I have more time to look at larger chunks of space for longer periods of time. I can help astronomers answer some really important “big picture” questions, which we didn’t have time for before.

Interviewer: Can you list some specific projects you’ll be working on?

Spitzer: I plan to continue studying exoplanets, including new “hot Jupiters” that Kepler is expected to find. I will also refine estimates of the rate at which our local universe, or space, is expanding. And I will stare at the very distant universe, trying to see some of the farthest objects possible. Oh, and I am also going to survey thousands of asteroids in our neck of the solar system, and get the first real estimate of their size distribution. This will tell us approximately how often big asteroids might come close to Earth.

Interviewer: That sounds scary.

Spitzer: Actually, this information will help us prepare for them. And NASA tracks near-Earth objects diligently. More information can only help.

Interviewer: Will you still take the pretty pictures?

Spitzer: You think my pictures are pretty? Thank you! Yes, I will still snap a lot of pictures. For instance, I will continue to probe cloudy star-forming regions in our galaxy, which often make dramatic pictures.

Interviewer: Anything else you’d like to add?

Spitzer: My cool years have been more than I could ask for, and I look forward to more adventures to come. I’d also like to thank all of the scientists and engineers who have worked so hard to make my mission an ongoing success. And, if any of my fans out there want more info, they can go to www.spitzer.caltech.edu/spitzer.

Irregular Galaxy

Most galaxies can be categorized by their shape. Our own Milky Way is a spiral galaxy, for example, and the largest galaxies in the Universe are elliptical galaxies. But some galaxies defy categorization. These are the irregular galaxies, and each one is unique in shape, age and structure.

Irregular galaxies are often chaotic in shape, with no central bulge or spiral arms. Although they used to have a more familiar shape, a dramatic collision with another galaxy has distorted their shape.

Astronomers maintain two classifications of irregular galaxies. Irr-I galaxies have some structure, but they’re still distorted enough that they can’t be classified as spiral, elliptical or lenticular shaped. Irr-II galaxies don’t have any structure at all.

The nearby Magellanic Clouds were once thought to be irregular galaxies. Although astronomers have detected a faint barred spiral shape.

There’s only one irregular galaxy in the Messier catalog of objects, and that’s M82; also known as the Cigar Galaxy. It’s located in the constellation Ursa Major about 12 million light-years away, and is famous for its heavy amounts of star formation. In fact, in infrared light, M82 is the brightest galaxy in the sky. Even in visible light, it’s 5 times brighter than the Milky Way.

We have written many articles about galaxies for Universe Today. Here’s an article about Hubble’s recent image of irregular galaxy M82.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

Elliptical Galaxy

Hubble image of a gas jet blasing from the core of M87. Credit: NASA, ESA, and J. Madrid (McMaster University)

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Our own Milky Way is classified as a spiral galaxy. But that’s just one of many classification of galaxies. One of the most common types are elliptical galaxies, named because they have an ellipsoidal (or egg) shape, and a smooth, almost featureless appearance.

Elliptical galaxies are usually large, containing hundreds of millions to trillions of stars. The biggest galaxies in the Universe are elliptical galaxies. They’re the result of many collisions between smaller galaxies, and all these collisions have destroyed the delicate spiral structure that we see in our own galaxy.

And they’re usually old. Elliptical galaxies look redder than spiral galaxies like the Milky Way. That’s because they contain old, red stars and have very low rates of star formation. All of the available gas and dust was already used up in the past, and now all that remains are these old red stars. They also have large populations of globular star clusters.

Elliptical galaxies are usually found in the most violent places in the Universe, like at the heart of galaxy clusters and in compact groups of galaxies. In these places, elliptical galaxies have had an accelerated life, with many galaxy mergers and several periods of star formation. These constant mergers and collisions increased their size and used up all the gas available for star formation.

The smallest dwarf elliptical galaxies are no larger than a globular cluster and can contain a mere 10 million stars. The largest elliptical galaxies can have well over 10 trillion stars. The largest known galaxy in the Universe, M87, is an elliptical galaxy.

We have written many articles about galaxies for Universe Today. Here’s an article about an ancient elliptical galaxy, and another elliptical galaxy where a black hole halted its formation.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

Sombrero Galaxy

Sombrero Galaxy

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One of the most beautiful images ever taken by the Hubble Space Telescope is the Sombrero Galaxy; also known as M104 or NGC 4594. This is an unbarred spiral galaxy located in the constellation of Virgo about 29 million light-years away.

Some of the defining features of the Sombrero Galaxy are its bright nucleus, large central bulge, and a prominent dust lane in its disk. The galaxy is seen nearly edge on, and so it has the appearance of a Sombrero hat. Since the galaxy has an apparent magnitude of +9.0, it’s easily visible in amateur telescopes; but too dim to see with the unaided eye.

The dark dust lane that you can see in the Hubble image is a symmetric ring that encloses the bulge of the galaxy. Astronomers have detected that it mostly contains hydrogen gas and dust. The bulk of star formation that occurs in the Sombrero Galaxy is happening within this ring.

As with our own Milky Way, astronomers have detected a supermassive black hole at the heart of the Sombrero Galaxy. Based on the speed of the stars orbiting around it, astronomers have calculated that it must have a mass of at least 1 billion suns. This is one of the most massive black holes detected in nearby galaxies.

If you want to look for the Sombrero Galaxy yourself, you’ll need good pair of 7×35 binoculars or a 4-inch telescope. The galaxy is located 11.5 degrees West of the star Spica, and 5.5 degrees northeast of Eta Corvi. With a medium sized telescope you can distinguish the bulge from the disk, and with a large telescope you should be able to see the dark dust lane.

We have written many articles about galaxies for Universe Today. Here’s an article about how the Sombrero Galaxy was imaged in three different wavelengths, and by three different observatories.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

Galaxy Wallpaper

Sombrero Galaxy

Nothing makes a better computer desktop wallpaper than a space picture. And some of the most beautiful pictures are galaxies. Here are a few galaxy wallpapers you can use to make your computer desktop look even better. You can see the small pictures here, and then click on an image to see a high-resolution version.

To update your computer desktop with one of these galaxy wallpapers, click to open up a high resolution version of the image. Then right-click on the image and choose “Set as Background”. In Mac OS X, you choose “Set as Desktop Background”.

This galaxy wallpaper is the Sombrero Galaxy, also known as M104. This photograph was captured by the Hubble Space Telescope, and shows the galaxy seen nearly edge on. It’s about 50,000 light-years across and is more than 28 million light-years from Earth.


Galaxy Triplet Arp 274.
Galaxy Triplet Arp 274.

This galaxy wallpaper shows the galaxy triplet Arp 274. This was also captured by the Hubble Space Telescope and although they look like they’re merging, they’re probably far apart. They just look like a collection from our point of view.


M74 Whirlpool Galaxy
M74 Whirlpool Galaxy

This is M74, also known as the Whirlpool Galaxy. This galaxy is a little smaller than the Milky Way, but we’re lucky enough to be seeing it almost face on, so we can see detailed structures in the core. You can also see the bright knots that contain regions of newly forming stars.

If you like more galaxy wallpapers, I highly recommend the wallpaper section of the Hubble Space Telescope website. You can get other galaxies, nebulae and star clusters.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

Our Neighbor, the Andromeda Galaxy

Andromeda Galaxy

To see most galaxies, you need at least a small telescope. But you can see the enormous Andromeda Galaxy, or Messier 31, with your own eyes; if you know where to look. The Andromeda Galaxy is located in the Andromeda constellation, and named after a princess in Greek mythology.

Andromeda is the largest galaxy in the Local Group, which includes the Milky Way, the Triangulum Galaxy, and dozens of smaller dwarf and irregular galaxies. A recent estimate gave Andromeda 700 billion solar masses. Our Milky Way is only 80% the mass of Andromeda.

The Andromeda galaxy was first observed by Persian astronomers, thousands of years ago, and was later cataloged by Charles Messier in 1764. He classified it as M31. In 1912, astronomers calculated its speed to be 300 kilometers per second, moving towards the Sun. Edwin Hubble first calculated the distance to Andromeda, by detecting cepheid variables in the galaxy. He measured that it was 450 kpc, or 2.5 million light-years away; well outside the Milky Way galaxy.

Recent estimates have calculated that Andromeda Galaxy is about 220,000 light-years in diameter, almost twice the estimate diameter of the Milky Way.

While other galaxies are moving away from us, Andromeda is on a collision course with the Milky Way. Our two galaxies will collide with one another in about 2.5 billion years, and begin forming a giant elliptical galaxy. It’s known to have 14 dwarf galaxies orbiting it in various stages of merger.

We have written many articles about Andromeda Galaxy for Universe Today. Here’s an article about the constellation Andromeda, which contains the Andromeda Galaxy, and here’s a beautiful picture of Andromeda captured by Spitzer.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

What is the Local Group?

Local Group of galaxies, including the massive members M31 (Andromeda Galaxy) and Milky Way, as well as other nearby galaxies. Credit: Wikipedia Commons/Antonio Ciccolella
Local Group of galaxies, including the massive members M31 (Andromeda Galaxy) and Milky Way, as well as other nearby galaxies. Credit: Wikipedia Commons/Antonio Ciccolella

The Milky Way is just one galaxy located in a vast cluster of galaxies known as the Local Group. This group contains more than 50 galaxies (mostly dwarf galaxies). The total size of the Local Group is 10 million light-years across, and it’s estimated to have a mass of 1.29 billion solar masses. The Local Group is just one collection of galaxies in the even bigger Virgo Supercluster.

The largest, most massive galaxies in the Local Group are the Milky Way, Andromeda and the Triangulum Galaxy.

Each of these galaxies has a collection of satellite galaxies surrounding them. For example, the Milky Way has Sagittarius Dwarf Galaxy, Large Magellanic Cloud, Small Magellanic Cloud, Canis Major Dwarf, Ursa Minor Dwarf, Draco Dwarf, Carina Dwarf, Sextans Dwarf, Sculptor Dwarf, Fornax Dwarf, Leo I, Leo II, and Ursa Major Dwarf.

Andromeda has satellite galaxies M32, M110, NGC 147, NGC 185, And I, And II, And III, And IV, And V, Pegasus dSph, Cassiopeia Dwarf, And VIII, And IX, and And X.

The Traingulum galaxy might be a satellite to Andromeda, and it might also have the Pisces Dwarf as a satellite.

The other members of the Local Group, not associated with another galaxy, include: IC10, IC1613, Phoenix Dwarf, Leo A, Tucana Dwarf, Cetus Dwarf, Pegasus Dwarf Irregular, Wolf-Lundmark-Melotte, Aquarius Dwarf, and Sagittarius Dwarf Irregular.

The first astronomer to identify the Local Group was Edwin Hubble, who called the collection the Local Group in his book, The Realm of Nebulae. Of course, at this time Hubble didn’t know that they were distant galaxies, separate from our own Milky Way, so he called them nebulae.

We have written many articles about galaxies for Universe Today. Here’s an article about a dwarf galaxy falling into the local group, and here’s an article about how the Universe doesn’t seem to be expanding evenly.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.

Is a Nearby Object in Space Beaming Cosmic Rays at Earth?

Fermi Telescope. Credit: NASA

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Data from several different space and ground based observatories imply the presence of a nearby object that is beaming cosmic rays our way. Scientists with the Fermi Space Telescope say an unknown pulsar may be close by, sending electrons and positrons towards Earth. Or another more exotic explanation is that the particles could come from the annihilation of dark matter. But whatever it is, the source is relatively close, surely in our galaxy. “If these particles were emitted far away, they’d have lost a lot of their energy by the time they reached us,” said Luca Baldini, a Fermi collaborator.

Comparing data from the Fermi space telescope with results from the PAMELA spacecraft and the High Energy Stereoscopic System (H.E.S.S.) ground-based telescope, the three observatories have found surprisingly more particles with energies greater than 100 billion electron volts (100 GeV) than expected based on previous experiments and traditional models.

Fermi is primarily a gamma ray detector, but its Large Area Telescope (LAT) is also tool for investigating the high-energy electrons in cosmic rays.

Video of the LAT detecting high energy particles.

Cosmic rays are hyperfast electrons, positrons, and atomic nuclei moving at nearly the speed of light. Unlike gamma rays, which travel from their sources in straight lines, cosmic rays wend their way around the galaxy. They can ricochet off of galactic gas atoms or become whipped up and redirected by magnetic fields. These events randomize the particle paths and make it difficult to tell where they originated. But determining cosmic-ray sources is one of Fermi’s key goals.

Using the LAT, which is sensitive to electrons and their antimatter counterparts, positrons, the telescope looked at the energies of 4.5 million cosmic rays that struck the detector between Aug. 4, 2008, and Jan. 31, 2009 and found more of the high-energy variety than expected, those with more than 1 billion electron volts (eV).

A spokesman from the Goddard Space Flight Center said the exact number of how many more is not currently available, due to peculiarities of the data.

But results from Fermi also refute other recent findings from a balloon-borne experiment. The Advanced Thin Ionization Calorimeter (ATIC) captured evidence for a dramatic spike in the number of cosmic rays at energies around 500 GeV from its high atmospheric location over Antarctica. But Fermi did not detect these energies.

“Fermi would have seen this sharp feature if it was really there, but it didn’t.” said Luca Latronico, a team member at the National Institute of Nuclear Physics (INFN) in Pisa, Italy. “With the LAT’s superior resolution and more than 100 times the number of electrons collected by balloon-borne experiments, we are seeing these cosmic rays with unprecedented accuracy.”

“Fermi’s next step is to look for changes in the cosmic-ray electron flux in different parts of the sky,” Latronico said. “If there is a nearby source, that search will help us unravel where to begin looking for it.”

Source: NASA