Jason Major, Author at Universe Today

March 18, 2015December 23, 2015 by Jason Major

Surprise – Mars Has Auroras Too!

Artist’s conception of MAVEN’s Imaging UltraViolet Spectrograph observing the “Christmas Lights Aurora" on Mars. (University of Colorado)

Just a day after skywatchers at mid- to upper-latitudes around the world were treated to a particularly energetic display of auroras on the night of March 17 as a result of an intense geomagnetic storm, researchers announced findings from NASA’s MAVEN mission of auroral action observed on Mars – although in energetic ultraviolet wavelengths rather than visible light.

Detected by MAVEN’s Imaging Ultraviolet Spectrograph (IUVS) instrument over five days before Dec. 25, 2014, the ultraviolet auroras have been nicknamed Mars’ “Christmas lights.” They were observed across the planet’s mid-northern latitudes and are the result of Mars’ atmosphere interacting directly with the solar wind.

Map of the UV aurora detected on Mars in Dec. 2014 (University of Colorado)

While auroras on Earth typically occur at altitudes of 80 to 300 kilometers (50 to 200 miles) and occasionally even higher, Mars’ atmospheric displays were found to be much lower, indicating higher levels of energy.

“What’s especially surprising about the aurora we saw is how deep in the atmosphere it occurs – much deeper than at Earth or elsewhere on Mars,” said Arnaud Stiepen, IUVS team member at the University of Colorado. “The electrons producing it must be really energetic.”

To a human observer on Mars the light show probably wouldn’t be very dramatic, though. Without abundant amounts of oxygen and nitrogen in its thin atmosphere a Martian aurora would be a dim blue glow at best, if not out of the visible spectrum entirely.

This isn’t the first time auroras have been spotted on Mars; observations with ESA’s Mars Express in 2004 were actually the first detections of the phenomenon on the Red Planet. Made with the spacecraft’s SPICAM ultraviolet spectrometer, the observations showed that Mars’ auroras are unlike those found anywhere else in the Solar System in that they are generated by particle interactions with very localized magnetic field emissions, rather than a globally-generated one (like Earth’s).

(So no, it’s not a total surprise… but it’s still very cool!)

In addition to auroras MAVEN also detected diffuse but widespread dust clouds located surprisingly high in the Martian atmosphere. It’s not yet understood what process is delivering dust so high – 150-300 kilometers up (93-186 miles) – or if it is a permanent or temporary feature.

Source: NASA and Nature

March 13, 2015March 15, 2015 by Jason Major

This Is The Asteroid That Didn’t Hit Us

All right, sure – there are a lot of asteroids that don’t hit us. And of course quite a few that do… Earth is impacted by around 100 tons of space debris every day (although that oft-stated estimate is still being researched.) But on March 10, 2015, a 12–28 meter asteroid dubbed 2015 ET cosmically “just missed us,” zipping past Earth at 0.3 lunar distances – 115,200 kilometers, or 71, 580 miles.*

The video above shows the passage of ~~2015 ET~~ across the sky on the night of March 11–12, tracked on camera from the Crni Vrh Observatory in Slovenia. It’s a time-lapse video (the time is noted along the bottom) so the effect is really neat to watch the asteroid “racing along” in front of the stars… but then, it was traveling a relative 12.4 km/second!

UPDATE 3/14: As it turns out the object in the video above is not 2015 ET; it is a still-undesignated NEO. (My original source had noted this incorrectly as well.) Regardless, it was an almost equally close pass not 24 hours after 2015 ET’s! Double tap. (ht to Gerald in the comments.) UPDATE #2: The designation for the object above is now 2015 EO6.

Continue reading “This Is The Asteroid That Didn’t Hit Us”

March 10, 2015December 23, 2015 by Jason Major

If You Could See in Radio These Are the Crazy Shapes You’d See in the Sky

"Color" radio image of galactic cluster Abell 2256. Credit: Owen et al., NRAO/AUI/NSF.

Even though it’s said that the average human eye can discern from seven to ten million different values and hues of colors, in reality our eyes are sensitive to only a very small section of the entire electromagnetic spectrum, corresponding to wavelengths in the range of 400 to 700 nanometers. Above and below those ranges lie enormously diverse segments of the EM spectrum, from minuscule yet powerful gamma rays to incredibly long, low-frequency radio waves.

Astronomers observe the Universe in all wavelengths because many objects and phenomena can only be detected in EM ranges other than visible light (which itself can easily be blocked by clouds of dense gas and dust.) But if we could see in radio waves the same way we do in visible light waves – that is with longer wavelengths being perceived as “red” and shorter wavelengths seen as “violet,” with all the blues, greens, and yellows in between – our world would look quite different… especially the night sky, which would be filled with fantastic shapes like those seen above!

View of the VLA in New Mexico. Image courtesy of NRAO/AUI.

Created from observations made at the Very Large Array in New Mexico, the image above shows a cluster of over 500 colliding galaxies located 800 million light-years away called Abell 2256. An intriguing target of study across the entire electromagnetic spectrum, here Abell 2256 (A2256 for short) has had its radio emissions mapped to the corresponding colors our eyes can see.

Within an area about the same width as the full Moon a space battle between magical cosmic creatures seems to be taking place! (In reality A2256 spans about 4 million light-years.)

See a visible-light image of A2256 by amateur astronomer Rick Johnson here.

The VLA radio observations will help researchers determine what’s happening within A2256, where multiple groups of galaxy clusters are interacting.

“The image reveals details of the interactions between the two merging clusters and suggests that previously unexpected physical processes are at work in such encounters,” said Frazer Owen of the National Radio Astronomy Observatory (NRAO).

Radio image of the night sky. (Credit: Max Planck Institute for Radio Astronomy, generated by Glyn Haslam.)

Learn more about NRAO and radio astronomy here, and you can get an idea of what our view of the Milky Way would look like in radio wavelengths on the Square Kilometer Array’s website.

Source: NRAO

March 4, 2015December 30, 2015 by Jason Major

Watch the Aurora Shimmer and Dance in Real Time

I for one have never witnessed the northern lights in person, and like many people I experience them vicariously through the photography and videos of more well-traveled (or more polar-bound) individuals. Typically these are either single-shot photos or time-lapses made up of many somewhat long-exposure images. As beautiful as these are, they don’t accurately capture the true motion of this upper atmospheric phenomenon. But here we get a look at the aurora as it looks in real time, captured on camera by Jon Kerr from northern Finland. Check it out above or watch in full screen HD on YouTube.

The video was shot with a full-frame mirrorless Sony a7S. See more of Jon’s aurora videos on YouTube here.

Video credit: Jon Kerr. HT SunViewer on Twitter.

February 18, 2015December 23, 2015 by Jason Major

New Horizons Now Close Enough to See Pluto’s Smaller Moons

Animation of images acquired by New Horizons on Jan. 27–Feb. 8, 2015. Hydra is in the yellow square, Nix is in the orange. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute.)

Now on the final leg of its journey to distant Pluto the New Horizons spacecraft has been able to spot not only the dwarf planet and its largest moon Charon, but also two of its much smaller moons, Hydra and Nix – the latter for the very first time!

The animation above comprises seven frames made of images acquired by New Horizons from Jan. 27 to Feb. 8, 2015 while the spacecraft was closing in on 115 million miles (186 million km) from Pluto. Hydra is noted by a yellow box and Nix is in the orange. (See a version of the animation with some of the background stars and noise cleared out here.)

What’s more, these images have been released on the 85th anniversary of the first spotting of Pluto by Clyde Tombaugh at the Lowell Observatory in Flagstaff, AZ.

“Professor Tombaugh’s discovery of Pluto was far ahead its time, heralding the discovery of the Kuiper Belt and a new class of planet. The New Horizons team salutes his historic accomplishment.”
– Alan Stern, New Horizons PI, Southwest Research Institute

Launched Jan. 19, 2006, New Horizons will make its closest pass of Pluto and Charon on July 14 of this year. It is currently 32.39 AU from Earth – over 4.84 billion kilometers away.

“It’s thrilling to watch the details of the Pluto system emerge as we close the distance to the spacecraft’s July 14 encounter,” said New Horizons science team member John Spencer from the Southwest Research Institute (SwRI). “This first good view of Nix and Hydra marks another major milestone, and a perfect way to celebrate the anniversary of Pluto’s discovery.”

Along with the distance between Earth and Pluto, New Horizons is also bridging the gap of history: a portion of Mr. Tombaugh’s ashes are being carried aboard the spacecraft, as well as several historic mementos.

Annotated and unannotated versions of the LORRI images (top and bottom); the right side has had Pluto's glare and additional background stars removed. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute) — Annotated and unannotated versions of the LORRI images from Feb. 8 (top and bottom); the right side has had Pluto’s glare and additional background stars removed. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

Each frame in the animation is a combination of five 10-second images taken with New Horizons’ Long-Range Reconnaissance Imager (LORRI) using a special mode that increases sensitivity at the expense of resolution. Celestial north is inclined 28 degrees clockwise from the “up” direction in these images.

The dark streaks are a result of overexposure on the digital camera’s sensitive detector.

Pluto and its moons, most of which were discovered while New Horizons was in development and en route. Charon was found in 1978, Nix and Hydra in 2005, Kerberos in 2011 and Styz in 2012. The New Horizons mission launched in 2007. Picture taken by the Hubble Space Telescope. Credit: NASA — Pluto and its moons, most of which were discovered while New Horizons was in development and en route. Charon was found in 1978, Nix and Hydra in 2005, Kerberos in 2011, and Styz in 2012. Credit: NASA/HST

Pluto has a total of five known moons: Charon, Hydra, Nix, Styx, and Kerberos. Pluto and Charon are within the glare of the image exposures and can’t be resolved separately, and Styx and Kerberos are too dim to be detected yet. But Hydra and Nix, each around 25–95 miles (40–150 km) in diameter, could be captured on camera.

More precise measurements of these moons’ sizes – and whether or not there may be even more satellites in the Pluto system – will be determined as New Horizons approaches its July flyby date.

Learn more about the New Horizons mission here.

Source: NASA

February 16, 2015December 23, 2015 by Jason Major

The First Images Are In from Rosetta’s Valentine’s Day Comet Flyby

The surface of 67P/C-G imaged by Rosetta on Feb. 14, 2015 from about 8.9 km (ESA/Rosetta/NavCam – CC BY-SA IGO 3.0)

On Saturday, Feb. 14, the Rosetta spacecraft swooped low over the surface of comet 67P/C-G in the first dedicated close pass of its mission, coming within a scant 6 km (3.7 miles) at 12:41 UTC. The image above is a mosaic of four individual NavCam images acquired just shortly afterwards, when Rosetta was about 8.9 km from the comet.

The 45m "Cheops" boulder on comet 67P/C-G (ESA/Rosetta/Navcam) — The 45m “Cheops” boulder on comet 67P/C-G (ESA/Rosetta/Navcam)

The view above looks across much of the Imhotep region along the flat bottom of comet 67P’s larger lobe. (See a map of 67P’s named regions here.) At the top is the flat “plain” where the Cheops boulder cluster can be seen – the largest of which is 45 meters (148 feet) across.

The zero phase angle of sunlight during the pass made for fairly even illumination across the comet’s surface.

The image scale on the full mosaic is 0.76 m/pixel and the entire view encompasses a 1.35 × 1.37 km-wide area.

Other NavCam images acquired before and after the pass have been assembled into mosaics – check those out below:

Four-image mosaic made from NavCam images acquired on Feb. 14, 2015 at a distance of 35 km. Credits: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0.

Four-image mosaic made from NavCam images acquired on Feb. 14, 2015 at a distance of 12.6 km. Credits: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0.

Four-image mosaic made from NavCam images acquired on Feb. 14, 2015 at 19:42 UTC at a distance of 31.6 km. Credits: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0.

In addition to NavCam images of 67P, Rosetta also acquired high-resolution OSIRIS images of the comet and gathered scientific data about its coma environment during the flyby. These data will be downlinked and processed over the next week or so.

Flybys will be regular parts of Rosetta’s operations over the course of 2015, but due to the comet’s increasing activity none will bring the spacecraft as close as this particular pass.

Rosetta is now moving out to a distance of about 250 km (155 miles) from 67P. Watch a video below of how the Feb. 14 flyby was planned and executed:

Source: ESA’s Rosetta blog

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(Also, on Feb. 9, Rosetta captured a full-frame NavCam image of 67P from 105 km. I’ve edited that image for additional contrast and added a blue tint. Enjoy!)

Comet 67P on Feb. 9, 2015 from 105 km (65 miles)

February 9, 2015December 23, 2015 by Jason Major

Rosetta’s Comet Really “Blows Up” in Latest Images

Jet activity on Comet 67P/C-G imaged on Jan. 31 and Feb. 3, 2015. Credits: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0. Edit by Jason Major.

First off: no, comet 67P/Churyumov-Gerasimenko is not about to explode or disintegrate. But as it steadily gets nearer to the Sun the comet’s jets are getting more and more active and they’re putting on quite a show for the orbiting Rosetta spacecraft! Click the image for a jeterrific hi-res version.

The images above were captured by Rosetta’s NavCam on Jan. 31 and Feb. 3 from a distance of about 28 km (17 miles). Each is a mosaic of four separate NavCam acquisitions and they have been adjusted and tinted in Photoshop by yours truly to further enhance the jets’ visibility. (You can view the original image mosaics and source frames here and here.)

These dramatic views are just a hint at what’s in store; 67P’s activity will only be increasing in the coming weeks and months and, this weekend, Rosetta will be swooping down for an extreme close pass over its surface!

Detail of 67P from the Feb. 3 NavCam image

This Saturday, Feb. 14, Rosetta will be performing a very close pass of the comet’s nucleus, soaring over the Imhotep region at an altitude of only 6 km (3.7 miles) at 12:41 UTC. This will allow the spacecraft to closely image the comet’s surface, as well as investigate the behavior of its jets and how they interact with its developing coma.

“The upcoming close flyby will allow unique scientific observations, providing us with high-resolution measurements of the surface over a range of wavelengths and giving us the opportunity to sample – taste or sniff – the very innermost parts of the comet’s atmosphere,” said Rosetta project scientist Matt Taylor.

Read more about Rosetta’s Valentine’s Day close pass here and watch an animation of how it will be executed below.

Source: ESA

UPDATE: Here’s an image of 67P captured by Rosetta on Feb. 6 from a distance of 124 km (77 miles) as it moved into a higher orbit in preparation of its upcoming close pass. It’s the first single-frame image of the comet since leaving bound orbits.

The image has been processed to add a contrasting tint and enhance jet activity. See the original image here.

Single-frame NavCam image of comet 67P/C-G imaged on Feb. 6, 2015. Credits: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0. Edited by Jason Major.

February 3, 2015December 23, 2015 by Jason Major

Rare Images of Red Sprites Captured at ESO

Distant sprites (right) captured from ESO's VLT by Photo Ambassador Petr Horálek. (P. Horálek/ESO)

At the ESO’s observatories located high in the Atacama Desert of Chile, amazing images of distant objects in the Universe are captured on a regular basis. But in January 2015, ESO photo ambassador Petr Horálek captured some amazing photos of much closer phenomena: red sprites flashing in the atmosphere high above distant thunderstorms.

The photo above was captured from ESO’s Paranal Observatory. A few days earlier during the early morning hours of Jan. 20 Petr captured another series of sprites from the La Silla site, generated by a storm over Argentina over 310 miles (500 km) away.

Sprites spotted from ESO's La Silla observatory by Petr Horálek — Sprites spotted from ESO’s La Silla observatory by Petr Horálek (left horizon)

So-named because of their elusive nature, sprites appear as clusters of red tendrils above a lighting flash, often extending as high as 55 miles (90 km) into the atmosphere. The brightest region of a sprite is typically seen at altitudes of over 40-45 miles (65-75 km).

Because they occur high above large storms, only last for fractions of a second and emit light in the portion of the spectrum to which our eyes are the least sensitive, observing sprites is notoriously difficult.

These furtive atmospheric features weren’t captured on camera until 1989. Continuing research has since resulted in more images, including some from the International Space Station. When they are spotted, sprites – and their lower-altitude relatives blue jets – can appear as bright as moderate aurorae and have also been found to emit radio noise. It has even been suggested that looking for sprite activity on other planets could help identify alien environments that are conducive to life.

Find out more about sprite research from the University of Alaska Fairbanks, and check out the PBS NOVA program “At the Edge of Space” below about a sprite hunt in the skies over Denver, CO conducted by a team of American scientists and Japanese filmmakers.

Source: ESO

January 31, 2015December 23, 2015 by Jason Major

Moroccan Meteorite May Be a 4.4-Billion-Year-Old Chunk of Dark Martian Crust

Mars! Martian meteorites make their way to Earth after being ejected from Mars by a meteor impact on the Red Planet. Image: NASA/National Space Science Data Center.

Mars is often referred to as the Red Planet. But its signature color is only skin-deep – or, I should say, dust-deep. Beneath its rusty regolith Mars has many other hues and shades as well, from pale greys like those found inside holes drilled by Curiosity to large dark regions that are the result of ancient lava flows. Now, researchers think we may have an actual piece of one of Mars’ dark plains here on Earth in the form of a meteorite that was found in the Moroccan desert in 2011.

Classified as NWA 7034 (for Northwest Africa) the meteorite is a 320-gram (11 oz.) piece of Martian basaltic breccia made up of small fragments cemented together in a dark matrix. Nicknamed “Black Beauty,” NWA 7034 is one of the oldest meteorites ever discovered and is like nothing else ever found on Earth.

According to a new study on a fragment of the meteorite by researchers from Brown University in Providence, Rhode Island and the University of New Mexico, Black Beauty is a 4.4-billion-year-old chunk of Mars’ dark crust – the only known piece of such to have landed on Earth.

While other meteorites originating from Mars have been identified, they are of entirely different types than Black Beauty.

The researchers used a hyperspectral imaging technique to obtain data from across the whole fragment. In doing this, the measurements matched what’s been detected from Mars orbit by NASA’s Mars Reconnaissance Orbiter.

“Other techniques give us measurements of a dime-sized spot,” said Kevin Cannon, a Brown University graduate student and lead author of a new paper published in the journal Icarus. “What we wanted to do was get an average for the entire sample. That overall measurement was what ended up matching the orbital data.”

In addition to indicating a truly ancient piece of another planet, these findings hint at what the surface of many parts of Mars might be like just below the rusty soil… a surface that’s been shattered and reassembled many times by meteorite impacts.

“This is showing that if you went to Mars and picked up a chunk of crust, you’d expect it to be heavily beat up, battered, broken apart and put back together,” Cannon said.

HiRISE image of dark terrain near Ganges Chasma (NASA/JPL/University of Arizona)

Source/read more at Brown University news.

January 27, 2015December 23, 2015 by Jason Major

Dawn Captures Best Images Ever of “Hipster Planet” Ceres

Animation of Ceres made from images acquired by Dawn on Jan. 25, 2015. (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

This is the second animation from Dawn this year showing Ceres rotating, and at 43 pixels across the images are officially the best ever obtained!

NASA’s Dawn spacecraft is now on final approach to the 950 km (590 mile) dwarf planet Ceres, the largest world in the main asteroid belt and the biggest object in the inner Solar System that has yet to be explored closely. And, based on what one Dawn mission scientist has said, Ceres could very well be called the Solar System’s “hipster planet.”

“Ceres is a ‘planet’ that you’ve probably never heard of,” said Robert Mase, Dawn project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “We’re excited to learn all about it with Dawn and share our discoveries with the world.”

Originally classified as a planet, Ceres was later categorized as an asteroid and then reclassified as a dwarf planet in 2006 (controversially along with far-flung Pluto.) Ceres was first observed in 1801 by astronomer Giuseppe Piazzi who named the object after the Roman goddess of agriculture, grain crops, fertility and motherly relationships. (Its orbit would later be calculated by German mathematician Carl Gauss.)

“You may not realize that the word ‘cereal’ comes from the name Ceres,” said Marc Rayman, mission director and chief engineer of the Dawn mission at JPL. “Perhaps you already connected with the dwarf planet at breakfast today.”

Ceres: part of this nutritionally-balanced Solar System!

Comparison of HST and Dawn FC images of Ceres taken nearly 11 years apart. Credit: NASA.

The animation above was made from images taken by Dawn framing camera on January 25, 2015 from a distance of about 237,000 km (147,000 miles). These are now the highest-resolution views to date of the dwarf planet, 30% more detailed than those obtained by Hubble in January 2004.

And there’s that northern white spot again too… seen in observations from earlier this month and in the 2003-04 HST images, scientists still aren’t quite sure what it is. A crater wall? An exposed ice deposit? Something else entirely? We will soon find out.

“We are already seeing areas and details on Ceres popping out that had not been seen before. For instance, there are several dark features in the southern hemisphere that might be craters within a region that is darker overall,” said Carol Raymond, Dawn deputy principal investigator at JPL.

Full-frame image from Dawn of Ceres on approach, acquired Jan. 25, 2015. (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

From now on, every observation of Ceres by Dawn will be the best we’ve ever seen! This new chapter of the spacecraft’s adventure has only just begun.

Dawn is scheduled to arrive at Ceres on March 6. Follow the progress of the Dawn mission here.

Source: NASA/JPL

*(Does this mean that Ceres has now gone “mainstream?” Hmm… oh well, it’s still cool.)