Swift Satellite Takes a Look at Comet ISON

The Ultraviolet/Optical Telescope aboard NASA's Swift imaged comet ISON (center) on Jan. 30, when it was located about 3.3 degrees from the bright star Castor in the constellation Gemini. At the time of this 5.5-minute optical exposure, ISON was about 5,000 times fainter than the limit of human vision. Credit: NASA/Swift/D. Bodewits, UMCP

Will the comet that’s been billed as the “the comet of the century” live up to expectations? Astronomers are getting a better idea of the makeup of Comet C/2012 S1 (ISON), and have now taken a look at it with the Swift satellite. They’ve been able to make initial estimates of the size of the comet’s nucleus.

“Comet ISON has the potential to be among the brightest comets of the last 50 years, which gives us a rare opportunity to observe its changes in great detail and over an extended period,” said Lead Investigator Dennis Bodewits, an astronomer at the University of Maryland College Park (UMCP.)

Bodewits and his team used Swift’s Ultraviolet/Optical Telescope (UVOT) to make initial estimates of the comet’s water and dust production, and then infer the size of its icy nucleus. They observed the comet on January 30 and then again late in February.

The January observations revealed that ISON was shedding about 112,000 pounds (51,000 kg) of dust, or about two-thirds the mass of an unfueled space shuttle, every minute. By contrast, the comet was producing only about 130 pounds (60 kg) of water every minute, or about four times the amount flowing out of a residential sprinkler system.

Similar levels of activity were observed in February, and the team plans additional UVOT observations.

Using the water and dust production, the astronomers estimated the size of ISON’s icy nucleus as roughly 3 miles (5 km) across, a typical size for a comet. This assumes that only the fraction of the surface most directly exposed to the Sun, about 10 percent of the total, is actively producing jets. The astronomers noted that these rates of water and dust production are relatively uncertain because of the comet’s faintness.

“The mismatch we detect between the amount of dust and water produced tells us that ISON’s water sublimation is not yet powering its jets because the comet is still too far from the Sun,” Bodewits said. “Other more volatile materials, such as carbon dioxide or carbon monoxide ice, evaporate at greater distances and are now fueling ISON’s activity.”

At the time, the comet was 375 million miles (604 million km) from Earth and 460 million miles (740 million km) from the Sun. ISON was at magnitude 15.7 on the astronomical brightness scale, or about 5,000 times fainter than the threshold of human vision.

Like all comets, ISON is a clump of frozen gases mixed with dust. Often described as “dirty snowballs,” comets emit gas and dust whenever they venture near enough to the Sun that the icy material transforms from a solid to gas, a process called sublimation. Jets powered by sublimating ice also release dust, which reflects sunlight and brightens the comet.

Typically, a comet’s water content remains frozen until it comes within about three times Earth’s distance to the Sun. While Swift’s UVOT cannot detect water directly, the molecule quickly breaks into hydrogen atoms and hydroxyl (OH) molecules when exposed to ultraviolet sunlight. The UVOT detects light emitted by hydroxyl and other important molecular fragments as well as sunlight reflected from dust.

The Deep Impact spacecraft also imaged Comet ISON in mid-January, and NASA and ESA are planning an observing campaign with the rovers and orbiters at Mars around October 1 when the inbound comet passes about 6.7 million miles (10.8 million km) from Mars.

“During this close encounter, comet ISON may be observable to NASA and ESA spacecraft now working at Mars,” said Michael Kelley, an astronomer at UMCP and also a Swift and CIOC team member. “Personally, I’m hoping we’ll see a dramatic postcard image taken by NASA’s latest Mars explorer, the Curiosity rover.”

Fifty-eight days later, on Nov. 28, ISON will make a sweltering passage around the Sun. The comet will approach within about 730,000 miles (1.2 million km) of its visible surface, which classifies ISON as a sungrazing comet. In late November, its icy material will furiously sublimate and release torrents of dust as the surface erodes under the sun’s fierce heat, all as sun-monitoring satellites look on. Around this time, the comet may become bright enough to glimpse just by holding up a hand to block the sun’s glare.

An important question is whether ISON will continue to brighten at the same pace once water evaporation becomes the dominant source for its jets. Will the comet sizzle or fizzle?

“It looks promising, but that’s all we can say for sure now,” said Matthew Knight, an astronomer at Lowell Observatory in Flagstaff, Arizona, and a member of the Swift and CIOC teams. “Past comets have failed to live up to expectations once they reached the inner solar system, and only observations over the next few months will improve our knowledge of how ISON will perform.”

Based on ISON’s orbit, astronomers think the comet is making its first-ever trip through the inner solar system. Before beginning its long fall toward the Sun, the comet resided in the Oort comet cloud, a vast shell of perhaps a trillion icy bodies that extends from the outer reaches of the planetary system to about a third of the distance to the star nearest the Sun.

Formally designated C/2012 S1 (ISON), the comet was discovered on Sept. 21, 2012, by Russian astronomers Vitali Nevski and Artyom Novichonok using a telescope of the International Scientific Optical Network located near Kislovodsk.

From now through October, Comet ISON tracks through the constellations Gemini, Cancer and Leo as it falls toward the sun. Credit: NASA's Goddard Space Flight Center/Axel Mellinger, Central Michigan Univ.
From now through October, Comet ISON tracks through the constellations Gemini, Cancer and Leo as it falls toward the sun. Credit: NASA’s Goddard Space Flight Center/Axel Mellinger, Central Michigan Univ.

Sungrazing comets often shed large fragments or even completely disrupt following close encounters with the Sun, but for ISON neither fate is a forgone conclusion.

“We estimate that as much as 10 percent of the comet’s diameter may erode away, but this probably won’t devastate it,” explained Knight. Nearly all of the energy reaching the comet acts to sublimate its ice, an evaporative process that cools the comet’s surface and keeps it from reaching extreme temperatures despite its proximity to the sun.

Following ISON’s solar encounter, the comet will depart the sun and move toward Earth, appearing in evening twilight through December. It will swing past Earth on Dec. 26, approaching within 39.9 million miles (64.2 million km) or about 167 times farther than the Moon.

Source: NASA

Watch Live Webcast: Witnessing Starbursts in the Early Universe

This schematic image represents how light from a distant galaxy is distorted by the gravitational effects of a nearer foreground galaxy, which acts like a lens and makes the distant source appear distorted, but brighter, forming characteristic rings of light, known as Einstein rings. An analysis of the distortion has revealed that some of the distant star-forming galaxies are as bright as 40 trillion Suns, and have been magnified by the gravitational lens by up to 22 times. Credit: ALMA (ESO/NRAO/NAOJ), L. Calçada (ESO), Y. Hezaveh et al.

Recently, a multinational team of astronomers found that massive, “dusty” galaxies were churning out stars much earlier than previously believed – as early as one billion years after the Big Bang (read our article about the discovery here).

Today, March 29, 2013 at 19:00 UTC (12:00 p.m. PDT, 3:00 pm EDT) the Kavli Foundation is hosting a live Google+ Hangout: “Witnessing Starbursts in the Early Universe.” You’ll have the chance to ask your questions about starburst galaxies, the early Universe and the incredible research being conducted by the South Pole Telescope and the Atacama Large Millimeter/submillimeter Array(ALMA) in Chile. Watch live in the window below, or see the replay later if you miss it live.

Science writer Bruce Lieberman will moderate, and three members of the research team will participate:

John E. Carlstrom – Leader of the 10-meter South Pole Telescope project and Deputy Director of the University of Chicago’s Kavli Institute for Cosmological Physics.
Dan P. Marrone – Assistant Professor in the Department of Astronomy at the University of Arizona.
Joaquin D. Vieira – Leader of the multinational team studying the galaxies discovered by the South Pole Telescope, Postdoctoral Scholar at the California Institute of Technology and member of Caltech’s Observational Cosmology Group.

Submit your questions before or during the webcast via Twitter (hashtag #KavliAstro) or by email to [email protected]

The webcast will also be available at: http://www.kavlifoundation.org/science-spotlights/spotlight-live-starbursts-and-early-universe

5 Weird Things About Vesta

An impact structure on asteroid Vesta resembling a snowman. Credit: NASA

When Heinrich Wilhelm Olbers first glimpsed Vesta on March 29, 1807 — this date in history — the asteroid was but a small point of light. Asteroid science was very, very new at the time as the first asteroid (Ceres) had been discovered only six years before.

Fast-forward 200-plus years and we can treat Vesta as a little world in its own right. NASA sent the Dawn spacecraft in orbit for about a year, which has produced a wealth of weird results. (Stay tuned for what happens at Dawn’s next port of call: Ceres.)

Below are five strange things we’ve discovered about Vesta:

1) Vesta has a fresh face.

This image from NASA’s Dawn spacecraft shows a close up of part of the rim around the crater Canuleia on the giant asteroid Vesta. Canuleia, about 6 miles (10 kilometers) in diameter, is the large crater at the bottom-left of this image. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI/Brown
This image from NASA’s Dawn spacecraft shows a close up of part of the rim around the crater Canuleia on the giant asteroid Vesta. Canuleia, about 6 miles (10 kilometers) in diameter, is the large crater at the bottom-left of this image. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI/Brown

Space “weathering” from tiny particles hitting the Moon has shaped the surface over time. Not so much on Vesta. It turns out the topography on the asteroid (and other factors) allow constant mixing of the surface, making it appear almost new even though the asteroid is several billion years old. “Vesta ‘dirt’ is very clean, well mixed and highly mobile,” said Carle Pieters, one of the lead authors and a Dawn team member based at Brown University, Providence, R.I. when the finding was made public.

2) Vesta might have stretch marks.

Dawn image of Vesta showing its nearly circumferential equatorial grooves (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)
Dawn image of Vesta showing its nearly circumferential equatorial grooves (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

While trying to wrap their mind around fault lines that circle Vesta’s equator, a group of scientists proposed these could be graban — features that show surface expansion. It’s possible these faults came to be after something big smashed into the planet, creating a gigantic crater with a peak that is almost three times as high as Mt. Everest. The expansion occurred as Vesta’s interior differentiated, or experienced a separation of its core, mantle and crust.

3) Vesta kind of looks like a planet.

'Rainbow-Colored Palette' of Southern Hemisphere of Asteroid Vesta from NASA Dawn Orbiter. This mosaic using color data obtained by the framing camera aboard NASA's Dawn spacecraft shows Vesta's southern hemisphere in false color, centered on the Rheasilvia impact basin, about 290 miles (467 kilometers) in diameter with a central mound reaching about 14 miles (23 kilometers) high. The black hole in the middle is data that have been omitted due to the angle between the sun, Vesta and the spacecraft.  The green areas suggest the presence of the iron-rich mineral pyroxene or large-sized particles. This mosaic was assembled using images obtained during Dawn's approach to Vesta, at a resolution of 480 meters per pixel. The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team.  Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
‘Rainbow-Colored Palette’ of Southern Hemisphere of Asteroid Vesta from NASA Dawn Orbiter. This mosaic using color data obtained by the framing camera aboard NASA’s Dawn spacecraft shows Vesta’s southern hemisphere in false color, centered on the Rheasilvia impact basin, about 290 miles (467 kilometers) in diameter with a central mound reaching about 14 miles (23 kilometers) high. The black hole in the middle is data that have been omitted due to the angle between the sun, Vesta and the spacecraft. The green areas suggest the presence of the iron-rich mineral pyroxene or large-sized particles. This mosaic was assembled using images obtained during Dawn’s approach to Vesta, at a resolution of 480 meters per pixel. The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Looking at Vesta in false color — wavelengths that let different kinds of minerals shine — show a veritable cornucopia of different types of stuff.  There’s the iron-rich mineral pyroxene, there’s diagenite material (characteristic of stony meteorites), and various particles of different sizes and ages. “Vesta is a transitional body between a small asteroid and a planet and is unique in many ways,” said mission scientist Vishnu Reddy of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. “We do not know why Vesta is so special.”

4) Vesta has hydrogen.

Hydrated minerals are circling the equator of the little world. It’s not quite water, but still an interesting find for scientists. “The source of the hydrogen within Vesta’s surface appears to be hydrated minerals delivered by carbon-rich space rocks that collided with Vesta at speeds slow enough to preserve their volatile content,” stated Thomas Prettyman, lead scientist for Dawn’s gamma ray and neutron detector (GRaND) from the Planetary Science Institute.

5) The northern and southern hemispheres look completely different.

Shaded-relief topographic map of Vesta southern hemisphere showing two large impact basins - Rheasilvia and Older Basin. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Shaded-relief topographic map of Vesta southern hemisphere showing two large impact basins – Rheasilvia and Older Basin.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

It’s fun to get to a new world and end up with something fundamentally surprising. Some of the very first pictures of Vesta showed a vast difference between different regions of the planet, giving scientists a workout in terms of figuring out how that came to be. “The northern hemisphere is older and heavily cratered in contrast to the brighter southern hemisphere where the texture is more smooth and there are lots of sets of grooves. There is a massive mountain at the South Pole. One of the more surprising aspects is the set of deep equatorial troughs,” said Carol Raymond, Dawn deputy principal investigator, of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

Here’s a video where you can see that for yourself:

Soyuz Makes Record-Breaking ‘Fast Track’ to Space Station

Screen capture from NASA TV of the Soyuz approaching the International Space Station with the Expedition 35/36 crew. Via NASA TV

It was same day, freaky-fast delivery for the Soyuz TMA-08M spacecraft bringing the crew of Expedition 35/36 to the International Space Station. The expedited flight had the crew arriving even quicker than expected, in just 5 hours and 45 minutes after launch. The new abbreviated four-orbit rendezvous with the ISS uses a modified launch and docking profile for the Russian ships. It has been tried successfully with three Progress resupply vehicles, but this is the first time it has been used on a human flight.

In the past, Soyuz manned capsules and Progress supply ships were launched on trajectories that required about two days, or 34 orbits, to reach the ISS. The new fast-track trajectory has the rocket launching shortly after the ISS passes overhead. Then, additional firings of the vehicle’s thrusters early in its mission expedites the time required for a Russian vehicle to reach the Station.

Liftoff of the Soyuz TMA-08M spacecraft took place at 4:43 p.m. EDT (20:43 UTC) on March 28 from the Baikonur Cosmodrome in Kazakhstan, and Russian commander Pavel Vinogradov, cosmonaut Aleksandr Misurkin and NASA astronaut Chris Cassidy docked with the ISS’s Poisk module at 10:28 p.m. EDT on Thursday (March 28; 0228 GMT Friday).

Hatches will be opened shortly, and Expedition 35 commander Chris Hadfield,astronaut Tom Marshburn and cosmonaut Roman Romanenko will welcome their new crewmates aboard. Update: Here’s the video of the hatch opening:

Find out more about the “fast-track” trajectory in our earlier articles here and here.

Space Station Crew Captures Soyuz Launch, As Seen from Orbit

Soyuz Rocket Launch - the moment of ignition, as-seen from their target, the Space Station. Credit: NASA/CSA/Chris Hadfield.

Just how much activity on Earth can be seen from orbit? In the dark of night, the Soyuz rocket launch on March 29/28, 2013 was bright enough to be seen by the International Space Station crew 350 km (220 miles) above. “Soyuz Rocket Launch – the moment of ignition, as-seen from their target, the Space Station,” tweeted ISS commander Chris Hadfield in sharing this image.

The new fast-track trajectory used for the first time for a crewed Soyuz has the rocket launching shortly after the ISS passes overhead, and so the ISS was in the perfect spot for the crew to witness the launch with their own eyes — at least with a camera and a zoom lens. The Soyuz TMA-08M spacecraft launched at 2:43 a.m. Friday local time from the Baikonur Cosmodrome in Kazakhstan (4:43 p.m. EDT, 20:43 UTC on March 28), carrying the crew of Pavel Vinogradov, Aleksandr Misurkin and Chris Cassidy.

The fast-track launch had the crew arriving in just 5 hours and 45 minutes after launch. This is the first crew to use this quick trajectory. It came with the added bonus of the launch being visible from space.

NASA Scientists Discuss Potential Comet Impact on Mars

The orbit diagram for Comet 2013 A1 as it will approach Mars in October, 2014.

There is a small but non-negligible chance that Comet 2013 A1 will hit Mars October of 2014. According the latest calculations from JPL, the comet is estimated to come within 120,000 kilometers (74,000 miles). In this video, various NASA scientists discuss the potential impact, and invariably view such an impact as scientifically very intriguing.

“I think of it as a giant climate experiment,” said Michael Meyer, lead scientist for the Mars Exploration Program. “An impact would loft a lot of stuff into the Martian atmosphere–dust, sand, water and other debris. The result could be a warmer, wetter Mars than we’re accustomed to today.”

An impact would likely have consequences for the current rovers on Mars. Meyer said the solar-powered Opportunity might have a hard time surviving if the atmosphere became opaque. Nuclear-powered Curiosity, though, would carry on just fine. He also notes that Mars orbiters might have trouble seeing the surface, for a while at least, until the debris begins to clear.

The trajectory for comet Siding Spring is being refined as more observations are made. Rob McNaught discovered this comet on Jan. 3, 2013, at Siding Spring Observatory in Australia, and looking back at archival observations has unearthed more images of the comet, extending the observation interval back to Oct. 4, 2012. Further refinement to its orbit is expected as more observational data is obtained.

Scientists estimate the nucleus of the comet is about 1 to 3 km in diameter. If it gets close to Mars and is grabbed by its gravity,and IF there was an impact it would be a substantial hit. “If it does hit Mars, it would deliver as much energy as 35 million megatons of TNT,” said Don Yeomans of NASA’s Near-Earth Object Program at JPL. According to what Yeomans says in this video, the current odds of it hitting Mars is about 1 in 2,000, but according to the parameters at JPL’s website, it appears the odds are about 1 in 10,000.

Source: Science@NASA

Watch “Fast-Track” Launch of Soyuz Live

Screenshot from NASA TV of the Soyuz TMA-09M spacecraft arriving at the International Space Station.



Live video by Ustream

Watch live the first “fast-track” human Soyuz flight to the International Space Station. The Soyuz TMA-08M crew will arrive at the ISS just five hours and 49 minutes after launch instead of the usual two days. Commander Pavel Vinogradov, flight engineer Alexander Misurkin and NASA astronaut Christopher Cassidy are scheduled for liftoff from the Baikonur Cosmodrome in Kazakhstan at 20:43 UTC (4:43:20 p.m. EDT) on Thursday, March 28, 2013. (If you missed the launch live, watch the video of it below:)
Continue reading “Watch “Fast-Track” Launch of Soyuz Live”

Weird Cloud ‘Coils’ Captured by Earth-Observing Satellite

Coil-like shapes in clouds, created by their passage over the Prince Edward Islands in the south Indian Ocean. Credit: NASA/Terra/MODIS.

These are some of the strangest looking clouds I’ve seen from the fleet of Earth-observing satellites. These coil-like or bow-wave-shaped clouds were created by the clouds passing over the Prince Edward Islands, in the south Indian Ocean. It was taken by the Terra satellite with the MODIS instrument (Moderate Resolution Imaging Spectroradiometer) on March 26, 2013.

Update: Vitaliy Egorov from the Russian website allmars.net has sent us an animation of these coil clouds as seen by the Russian satellite Elektro-L:

Animation is made up of 17 frames made satellite “Electro-L” from 12:30 to 20:30 GMT March 26, 2013 at 1 frame per 30 minutes. Photo: Roscosmos / NTSOMZ / Electro-L / allmars.net.

The images are taken from a different angle than the Terra satellite. You can see more at Egorov’s website.

NASA says MODIS is playing a vital role in the development of validated, global, interactive Earth system models able to predict global change accurately enough to assist policy makers in making sound decisions concerning the protection of our environment.

Comet PANSTARRS En Route To Andromeda Galaxy Encounter

Comet C/2011 L4 Panstarrs, taken from New Mexico Skies between on March 25, 2013 using an FSQ 10.6 and STL11K camera. 65 frames over 18 min each with an exposure time of 2.0 sec. The stars have been enhanced for effect. Credit and copyright: Joseph Brimacombe.

Get ready for an comet encounter of the extragalactic kind. In less than a week, Comet PANSTARRS will slide by the Andromeda Galaxy, the brightest galaxy visible in northern hemisphere skies. On and around that date, you’ll be able to see them both glowing softly together in late evening and early morning twilight.

The Andromeda Galaxy is the closest large galaxy to our Milky Way. It's easily visible in binoculars in the constellation Andromeda. Credit: Adam Evans
The Andromeda Galaxy is the closest large galaxy to our Milky Way. It’s easily visible in binoculars in the constellation Andromeda. Credit: Adam Evans

Their apparent proximity if of course pure sleight of hand; the comet will be a mere 121 million miles (195 million km) from Earth on that date compared to Andromeda’s 2.5 billion light years. For what it’s worth, 121 million miles (195 million km) equates to 0.00002 light years. Let’s just say they’re WAY far apart in reality. Their juxtaposition will make for enjoyable binocular viewing as well as offer astrophotographers an opportunity to create a classic image.

Comet PANSTARRS on March 22 photographed with a 200mm lens at dusk on a motorized tracking platform. Credit: Bob King
Comet PANSTARRS on March 22 photographed with a 200mm lens at dusk on a motorized tracking platform. Credit: Bob King

Last night under the clearest of skies I easily found Comet C/2011 L4 PANSTARRS in the constellation Andromeda about 15 degrees above the horizon an hour after sunset. Twilight was still a factor as was the rising full moon. That’s probably why the comet remained at the very limit of naked eye vision. Binoculars – I use 10x50s – clearly showed the comet’s bright parabolic head and two degrees (four full diameters) of tail streaming up and to the right.

Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet.  The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium
Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet. The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium

The comet has faded considerably since it first emerged into the evening twilight three weeks ago. Its head now shines around magnitude 3.5 and is noticeably fainter than the stars of the Big Dipper. As compensation, PANSTARRS is now easier to find, since it’s both higher up in the sky and near a string of moderately bright stars in the constellation Andromeda.

PANSTARRS treks northward through Andromeda en route to the W of Cassiopeia in the next two weeks. It won’t be long before the comet becomes circumpolar and remains visible all night long. The term refers to celestial objects that circle around the pole star without setting. The Big Dipper is the most familiar circumpolar constellation for much of the U.S. and Canada.

Comet PANSTARRS in the early dawn sky during the first part of April. The map shows the sky facing northeast about 75 minutes before sunrise. Stellarium
Comet PANSTARRS in the early dawn sky during the first part of April. Once again, you can use Cassiopeia to help get you there. Don’t forget binoculars! They’re now essential to seeing the comet. The map shows the sky facing northeast about 75 minutes before sunrise. Stellarium

On its journey to all-night visibility, PANSTARRS started pulling a double-shift this week. You can now see it both at dusk and at dawn. Although a bright moon will compromise the dawn view for a few days, you can watch for the comet low in the northeastern sky starting about hour and 15 minutes before sunrise. For the moment, it’s about the same altitude above the horizon during both morning and evening hours. Evening is still preferred only because the bright moon has finally departed the sky during the hour or so the comet is visible.

Comet C/2011 L4 PANSTARRS sports a broad dust tail and a narrower red-tinted tail in this photo made on March 15, 2013. The red tail may be from sodium atoms released by materials colliding with each other as they leave the comet under pressure and heat from the sun. Credit: José J. Chambó
Jose Chambo’s photo of Comet C/2011 L4 PANSTARRS from Spain on March 15 reveals a broad dust tail and narrower red-tinted tail. The red tail may be from sodium atoms released by materials colliding with each other as they jet off the comet’s nucleus. Click image to see more photos. Credit: José J. Chambó

Through my 15-inch telescope last night,  PANSTARRS’ head held a brilliant topaz gem – the false nucleus. This tiny ball of bright, fuzzy light contains the icy comet itself,  hidden behind a fury of its own dust and vapor boiled off by the sun’s heat.

Here’s some additional images and videos of PANSTARRS that Universe Today has received from readers:

Zlatan Merakov created this timelapse from images he took on March 20 from Smolyan, Bulgaria.

The view of Comet PANSTARRS  L4  on 03-22-2013 over Warrenton, Virginia.  Modified Canon Rebel Xsi DSLR 30 second exposure, ISO 1600, University Optics 80mm  F6 Refractor (600mm). Credit and copyright: John Chumack.
The view of Comet PANSTARRS L4 on 03-22-2013 over Warrenton, Virginia.
Modified Canon Rebel Xsi DSLR
30 second exposure, ISO 1600, University Optics 80mm F6 Refractor (600mm). Credit and copyright: John Chumack.
Comet C/2011 Pan-STARRS over Gradara Castle in Italy. Credit and copyright: Niki Giada.
Comet C/2011 Pan-STARRS over Gradara Castle in Italy. Credit and copyright: Niki Giada.

Watch NOVA’s “Meteor Strike”

Frame grab from a video of the Feb. 15, 2013 Russian fireball by Aleksandr Ivanov

Watch Meteor Strike on PBS. See more from NOVA.

It was an event that took the world by surprise: On the morning of February 15, 2013 a 7,000-ton asteroid crashed into the Earth’s atmosphere. According to NASA, the Siberian meteor exploded with the power of 30 Hiroshima bombs and was the largest object to burst in the atmosphere since the Tunguska event of 1908. This video from PBS’s science show NOVA aired last night on television and is now available to watch online. (Note: the video may not yet be available to watch in all areas of the world.)

The show reveals what scientists have gleaned so far about this object from the numerous dashcam videos in Russia and other data, and how this event could have been much worse.

It features interviews with several scientists, including Peter Brown and Margaret Campbell-Brown from the University of Western Ontario, Mark Boslough from the University of New Mexico, Dan Durda from the Southwest Research Institute and Apollo 9 astronaut Rusty Schweickart, who is now Chair Emeritus of the B612 Foundation, the organization that is building the “Sentinel” telescope to search for asteroids heading for Earth.