Hubble's view of Comet ISON on Oct. 9, 2013. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
We’ve been showing images of Comet ISON from amateur astronomers around the world, but now that NASA is back from the government shutdown, here’s more proof that the comet is still intact and has not disintegrated … despite some predictions to the contrary. This image was taken on October 9.
NASA explains:
In this NASA Hubble Space Telescope image taken on October 9, the comet’s solid nucleus is unresolved because it is so small. If the nucleus broke apart then Hubble would have likely seen evidence for multiple fragments.
Moreover, the coma or head surrounding the comet’s nucleus is symmetric and smooth. This would probably not be the case if clusters of smaller fragments were flying along. What’s more, a polar jet of dust first seen in Hubble images taken in April is no longer visible and may have turned off.
This color composite image was assembled using two filters. The comet’s coma appears cyan, a greenish-blue color due to gas, while the tail is reddish due to dust streaming off the nucleus. The tail forms as dust particles are pushed away from the nucleus by the pressure of sunlight. The comet was inside Mars’ orbit and 177 million miles (284 million km) from Earth when photographed.
So, its not disintegrating, its not a three-piece body, its not a UFO… instead Comet ISON is turning out to be a rather average, ordinary comet. How has this comet sparked predictions that have gone from “bright as the full moon” to “disintegrating as we speak,” asked Josh Sokol from the Hubble ISON blog? “Simply put, ISON peaked early. When it was first discovered, way out past Jupiter, ISON was really bright,” Sokol wrote. “Extrapolated, those first data points made ISON look like it would shine even more as it got closer — and when it didn’t, the coverage seesawed back toward calling ISON a total bust.”
But ISON is still en route to the Sun. It will pass closest to the Sun on November 28, and if it remains intact after that close pass, it will make its closest approach to Earth on December 26, at a distance of 39.9 million miles (64 million km).
NASA is having a live Hangout with Hubble comet scientists to discuss the new image and latest research findings about ISON today (Oct. 17) at 4 p.m. EDT (20:00 UTC).
"The pic doesn't do the northern lights justice. Covered the whole sky. Truly amazing!" wrote NASA astronaut Mike Hopkins on Twitter Oct. 9.
Isn’t that aurora facing the wrong way? Not if you’re in space!
NASA astronaut Mike Hopkins tweeted this picture from his perch on the International Space Station a few days ago. He sounds jazzed to be on his first mission: “Can’t believe this is really me from the Cupola and that I’ve been in space for almost 3 weeks now!” he wrote on Twitter Oct. 15.
We’d be pretty excited, too! Luca Parmitano (from the European Space Agency) is also on his first trip into space. In between their manyexperiments, the rookies must relish the opportunity to take pictures of the view. Which image of theirs below is your favorite? Did we miss any notable shots? Let us know in the comments.
“Blue liquid silk folds and unfolds in the #Caribbean.” European Space Agency astronaut Luca Parmitano, Oct. 16, 2013. (Twitter)“Not something you see every day first hand. With features like this, Dubai stands out from 260 miles up.” NASA astronaut Mike Hopkins, Oct. 14, 2013. (Twitter)“The sculpted mountains of the Iranian deserts.” European Space Agency astronaut Luca Parmitano, Oct. 15, 2013. (Twitter)“What remains of Hurricane Phailin after it reached land.” European Space Agency astronaut Luca Parmitano, Oct. 13, 2013. (Twitter)
And of course, they’re grinning like crazy up there.
“Impossible not to smile with such a view!” European Space Agency astronaut Luca Parmitano, Oct. 16, 2013. (Twitter)“Can’t believe this is really me from the Cupola and that I’ve been in space for almost 3 weeks now!” NASA astronaut Mike Hopkins, Oct. 15, 2013. (Twitter)
Saturn and its rings, as seen from above the planet by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute/Gordan Ugarkovic
So what did NASA do during the US government shutdown? You can’t just turn off spacecraft that are operating millions of miles away, so missions like the Mars rovers and the Cassini spacecraft at Saturn continued to send back images to Earth during the 16 days that most of NASA wasn’t up and running like usual. On October 10, 2013, as Cassini flew high above the planet’s equatorial plane, the spacecraft’s camera took 36 images of Saturn, a dozen each using the various red, green, and blue filters used to create color images. The images were transferred back to Earth and put on the Cassini raw images page. Gordan Ugarkovic from Croatia, and a member of the image editing wizards at UnmannedSpaceflight.com, grabbed the raw files, processed them, then assembled the images into this jaw-dropping mosaic.
This is a view from Saturn that we could never get from Earth; only a spacecraft orbiting the planet could take it. You can see the north pole and the swirling maelstrom of clouds that creates the hexagonal polar vortex, the thin bands in Saturn’s atmosphere, and — of course — what really stands out is the incredible view of Saturn’s rings. To see the original 3 MB version, see this page on UMSF.
“You shouldn’t be surprised to see processing artifacts here and there,” cautioned Ugarkovic via email to Universe Today. “It is, after all, based on raw JPEG images only.”
But in the words of UMSF’s Astro0, “That’s the sort of view I’ve dreamed I would only ever see in a science fiction movie or if we had some kind of amazing futuristic spacecraft orbiting around that distant ringed planet….WAIT! We do!”
For more of what NASA did during the shutdown, Bill Dunford at Riding With Robots put together a great summary, quoting the @SarcasticRover that “You can’t shut down awesome.” Bill started the #ThingsNASAMightTweet hashtag that reminded everyone of all the things NASA does, but they couldn’t tweet about during the shutdown. People from around the world chimed in, adding what was important to them about NASA, and as of today, tweets with that hashtag have passed 27 million impressions.
A picture of the object J1000+0221, which demonstrates the most distant gravitational lens ever discovered. This Hubble picture shows a normal galaxy's center region (the glow in the picture), but the object is also aligned with a younger, star-creating galaxy that is in behind. The object in the foreground pulls light from the background galaxy with gravity -- making rings of pictures. Credit: NASA/ESA/A. van der Wel
Here’s a picture of what deflected light looks like from 9.4 billion years away. This is the most faraway “gravitational lens” that we know of, and a demonstration of how a galaxy can bend the light of an object behind it. The phenomenon was first predicted by Einstein, and is a handy way of measuring mass (including the mass of mysterious dark matter.)
“The discovery was completely by chance,” stated Arjen van der Wel, who is with the Max Planck Institute for Astronomy in Heidelberg, Germany.
“I had been reviewing observations from an earlier project when I noticed a galaxy that was decidedly odd. It looked like an extremely young galaxy, but it seemed to be at a much larger distance than expected. It shouldn’t even have been part of our observing program.”
The alignment between object J1000+0221 and the object in behind is so perfect that you can see rings of light being formed in the image. Scientists previously believed this kind of lens would happen very rarely. This leaves two possibilities: that the astronomy team was lucky, or there are way more young galaxies than previously thought.
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.
“Gravitational lenses are the result of a chance alignment. In this case, the alignment is very precise,” a press release on the discovery stated.
“To make matters worse, the magnified object is a starbursting dwarf galaxy: a comparatively light galaxy … but extremely young (about 10-40 million years old) and producing new stars at an enormous rate. The chances that such a peculiar galaxy would be gravitationally lensed is very small. Yet this is the second starbursting dwarf galaxy that has been found to be lensed.”
“This has been a weird and interesting discovery,” added van der Wel. “It was a completely serendipitous find, but it has the potential to start a new chapter in our description of galaxy evolution in the early universe.”
The research will be available soon in the Astrophysical Journal; in the meantime, check out a preprint version on Arxiv.
A message on the NASA 360 Twitter feed the day employees returned to work after a 16-day government shutdown in October 2013.
After 16 days off the job, most employees at NASA returned to work today (Oct. 17). The good news came after a late-night deal by U.S. politicians to reopen government activities until Jan. 15 and raise the debt limit — originally expected to expire today — until Feb. 7. Democrats and Republicans were battling over the implementation of a new health care law; more details on how the deal was reached are available in this New York Times article.
During the shutdown, only mission-essential functions at NASA were completed except at areas such as the Jet Propulsion Laboratory, which are run by contractors. Twitter, Facebook and social media updates went silent. Missions were run on a needs-only basis, and for a while it looked as though the upcoming MAVEN mission to Mars might be delayed (although it got an exception due to its role as a communications relay for NASA’s rovers.)
So you can imagine the happiness on social media when NASA employees returned to work.
Given the length of the shutdown, not all work can just start immediately. Experiments have been left unattended for more than two weeks. Equipment needs to be powered back on. Cancelled meetings and travel arrangements need to, as it is possible, be rebooked.
At NASA’s Marshall Space Flight Center, spokesperson Don Amatore asked employees to be mindful of safety precautions, according to All Alabama. He also stated that “liberal leave” is in effect for employees today and on Friday, meaning that employees are able to take time off without requesting it beforehand — as long as their supervisors know.
Several Twitter reports from NASA contractors on Thursday also indicated that they were unsure if they would be coming back to work on that day, or at some point in the near future. The agency, however, was reportedly sending automated telephone updates to employees and contractors advising them to check with their supervisors for information.
The Stratospheric Observatory for Infrared Astronomy, or SOFIA, 747SP basks in the light of a full moon shining over California’s Mojave Desert. Photo / Tom Tschida
The long-term effects of the shutdown are still coming to light. Certain NASA researchers who planned Antarctic work this year may lose their entire field season. Also, some researchers using NASA or government telescopes missed their “window” of telescope time. “SOFIA remains grounded as a testament to stupidity. Europa keeps her secrets,” wrote Mike Brown, a professor of planetary astronomy at the California Institute of Technology, on Twitter Oct. 13 about NASA’s Stratospheric Observatory for Infrared Astronomy.
Additionally, the S&P ratings agency noted that the U.S. economy lost $24 billion due to the shutdown, which is more than the initial $17.7 billion request for NASA’s budget in fiscal 2014. Given the agency is in the midst of budget negotiations and is worried about the viability of the commercial crew program, among other items, any long-term economic damage could hurt NASA for a while.
NASA and other government agencies also have only three months of relative stability until the government reaches another funding deadline. What do you think will happen next? Let us know in the comments.
The evidence that the Universe began with the Big Bang is very compelling. 13.8 billion years ago, the entire Universe was compressed into a microscopic singularity that grew exponentially into the vast cosmos we see today. But what does the future hold? How will the Universe end?
Astronomers have been pondering the ultimate fate of the Universe for thousands of years. In the last century, cosmologists considered three outcomes for the end of everything, and it all depended on the critical density of the Universe. If this critical density was high, then there was enough mutual gravity to slow and eventually halt the expansion. Billions of years in the future, it would then collapse in on itself again, perhaps creating another Big Bang. This is known as a closed Universe, and the final result is the Big Crunch.
If the critical density was low, then there wouldn’t be enough gravity to hold things together. Expansion would continue on forever and ever. Stars would die, galaxies would be spread apart, and everything would cool down to the background temperature of the Universe. This is an open Universe, and the end is known as the Big Freeze.
And if the critical density was just right, the Universe’s expansion goes on forever, but it’s always slowing down, reaching a dead stop in an infinite amount of time. This creates a Flat Universe… also a Big Freeze.
Fortunately, astronomers were able to measure the critical density of the Universe, using NASA’s WMAP spacecraft, and they discovered that the actual density of the Universe predicts a flat Universe. So that’s it, right? Of the three choices, the answer is #3.
Unfortunately, nature had other plans, and came up with a reality that nobody expected. In 1998, a team of astronomers were observing distant supernovae to get a sense of how fast the Universe is slowing down and they made an amazing discovery. Instead of decelerating, as predicted by the critical density of the Universe, the expansion of the Universe is actually speeding up.
Some mysterious force is pushing galaxies faster and faster away from each other, accelerating the expansion of the Universe. We now call this force “dark energy”, and for the time being, astronomers have no idea what it is. All we know is that it’s pushing the Universe apart. Distant galaxies are being accelerated away from us, and in trillions of years from now, they will cross the beyond the cosmic horizon and disappear from view. The evidence that we live in a vast Universe will disappear with them.
Galaxies spinning farther and farther away from each other
But there’s a further unsettling possibility about dark energy. Maybe the expansion pressure will increase, eventually overwhelming gravity on a local level. Galaxies will get torn apart, and then Solar Systems, and eventually atoms themselves will be shredded by the increasing dark energy – this idea is known as the Big Rip.
So how will the Universe end? The force of dark energy will continue to accelerate the expansion of the Universe until distant galaxies disappear. Galaxies will use up all the gas and dust for stars and go dark, perhaps becoming black holes. Those black holes will decay and maybe matter itself will decay into pure energy. The entire Universe will become a cold, quiet place, where single photons are stretched across light years of space.
Don’t worry, though, that won’t be for quadrillions of years from now.
This detailed view shows the central parts of the nearby active galaxy NGC 1433. The dim blue background image, showing the central dust lanes of this galaxy, comes from the NASA/ESA Hubble Space Telescope. The coloured structures near the centre are from recent ALMA observations that have revealed a spiral shape, as well as an unexpected outflow, for the first time. Credit: ALMA (ESO/NAOJ/NRAO)/NASA/ESA/F. Combes
Did you ever wonder what it would be like to observe what happens to a galaxy near a black hole? For all of us who remember that wonderful Disney movie, it would be a remarkable – if not hypnotic – experience. Now, thanks to the powerful observational tools of the Atacama Large Millimeter/submillimeter Array (ALMA), two international astronomy teams have had the opportunity to study the jets of black holes near their galactic cores and see just how they impact their neighborhood. The researchers have captured the best view so far of a molecular gas cloud surrounding a nearby, quiescent black hole and were gifted with a surprise look at the base of a massive jet near a distant one.
These aren’t lightweights. The black holes the astronomers are studying weigh in a several billion solar masses and make their homes at the center of nearly all the galaxies in the Universe – including the Milky Way. Once upon a time, these enigmatic galactic phenomena were busy creatures. They absorbed huge amounts of matter from their surroundings, shining like bright beacons. These early black holes thrust small amounts of the matter they took in through highly powerful jets, but their current counterparts aren’t quite as active. While things may have changed a bit with time, the correlation of black hole jets and their surroundings still play a crucial role in how galaxies evolve. In the very latest of studies, both published today in the journal Astronomy & Astrophysics, astronomers employed ALMA to investigate black hole jets at very different scales: a nearby and relatively quiet black hole in the galaxy NGC 1433 and a very distant and active object called PKS 1830-211.
“ALMA has revealed a surprising spiral structure in the molecular gas close to the center of NGC 1433,” says Françoise Combes (Observatoire de Paris, France), who is the lead author of the first paper. “This explains how the material is flowing in to fuel the black hole. With the sharp new observations from ALMA, we have discovered a jet of material flowing away from the black hole, extending for only 150 light-years. This is the smallest such molecular outflow ever observed in an external galaxy.”
Need feedback? Well, that’s exactly what this process is called. “Feedback” may enlighten us to the relationship between black hole mass and the mass of the surrounding galactic bulge. The black hole consumes gas and becomes active, but then it creates jets which purge gas from its proximity. This halts star formation and controls the growth of the central bulge. In PKS 1830-211, Ivan Marti-Vidal (Chalmers University of Technology, Onsala Space Observatory, Onsala, Sweden) and his team witnessed a supermassive black hole with a jet, “but a much brighter and more active one in the early universe. It is unusual because its brilliant light passes a massive intervening galaxy on its way to Earth, and is split into two images by gravitational lensing.”
Are supermassive black holes messy eaters? You bet. There have been occasions when a supermassive black hole will unexpectedly consume a staggering amount of mass which, in turn, turbo-charges the power of the jets and lights up the radiation output to the very pinnacle of energy output. This energy is emitted as gamma rays, the shortest wavelength and highest energy form of electromagnetic radiation. And now ALMA has, by chance, caught one of these events as it happened in PKS 1830-211.
“The ALMA observation of this case of black hole indigestion has been completely serendipitous. We were observing PKS 1830-211 for another purpose, and then we spotted subtle changes of color and intensity among the images of the gravitational lens. A very careful look at this unexpected behavior led us to the conclusion that we were observing, just by a very lucky chance, right at the time when fresh new matter entered into the jet base of the black hole,” says Sebastien Muller, a co-author of the second paper.
The main image, showing the nearby active galaxy NGC 1433, comes from the NASA/ESA Hubble Space Telescope. The coloured structures near the centre shown in the insert are from recent ALMA observations that have revealed a spiral shape, as well as an unexpected outflow, for the first time. Credit: ALMA (ESO/NAOJ/NRAO)/NASA/ESA/F. CombesAs with all astronomical observations, the key to discovery is confirmation. Did the ALMA findings show up on other telescopic observations? The answer is yes. Thanks to monitoring observations with NASA’s Fermi Gamma-ray Space Telescope, there was a definite gamma ray signature exactly where it should be. Whatever was responsible for the scaling up of radiation at ALMA’s long wavelengths was also responsible for making the light of the black hole jet flare impressively.
“This is the first time that such a clear connection between gamma rays and submillimeter radio waves has been established as coming from the real base of a black hole’s jet,” adds Sebastien Muller.
It isn’t the end of the story, however. It’s just the beginning. ALMA will continue to probe into the mysterious workings of supermassive black hole jets – both near and far. Combes and her investigative team are already observing close active galaxies with ALMA, and even a unique object cataloged as PKS 1830-211. The research will continue, and with it we may one day have answers to many questions.
“There is still a lot to be learned about how black holes can create these huge energetic jets of matter and radiation,” concludes Ivan Marti-Vidal. “But the new results, obtained even before ALMA was completed, show that it is a uniquely powerful tool for probing these jets — and the discoveries are just beginning!”
A unique panoramic image from of the aurora seen over Norway on October 14. Credit and copyright: Göran Strand.
How fun is this?! “Here’s a panoramic image from the aurora on October 14,” wrote Swedish astrophotographer Göran Strand. “I’ve made a small world trapped inside a bubble floating in space. And a lonely photographer is trying to capture the ongoing aurora with his camera.”
Synthetic view of the waxing Moon as viewed from Earth on 2013-10-15 17:00:00 UTC [NASA/GSFC/Arizona State University].
Take a look around the Moon… no, really, take a good look AROUND the Moon! This is a fantastic animation of our planetary partner in space made by the folks on the Lunar Reconnaissance Orbiter team at Arizona State University. Assembled from reflectance maps and digital terrain models created from data gathered by LRO’s wide-angle camera, this full 360-degree portrait of the Moon shows its surface as if it were receiving direct top-down sunlight on all points — a physical impossibility, yes, but it gives us a great view of pretty much everything (including the far side, which for obvious reasons most of us never get a good look at.)
In addition to shining a light on the lunar landscape (pun intended) the vast amounts of data used to create the view above can also be used to calculate the type of illumination that would be found on any point on the Moon, at any time, allowing for better targeted observation planning with LRO’s narrow-angle camera.
Read more about how this process was engineered here, and see a more recent result of these new capabilities below:
While the image above wouldn’t have been visible from anywhere on North America on October 15, 2013 at 2 p.m. EDT, it’s what would have been seen in the night sky above Mumbai — but no international calls to India were needed, as the view could simply be generated from the LRO WAC data and a ray-tracing algorithm that plots the angles of light and shadow across the lunar terrain. Voilà — it’s Insta-Moon*!
*Some assembly required.
Read more on the Arizona State University LROC site here (and to really blow your mind, watch the high-resolution version here.)
Curiosity is only eight miles (five kilometers) from a hematite-rich ridge at the bottom of Mount Sharp (Aeolis Mons). Credit: NASA/JPL-Caltech/MSSS
So Curiosity has been on Mars for an Earth year and is now, slowly, making its way over to that ginormous mountain — Mount Sharp, or Aeolis Mons — in the distance. The trek is expected to take at least until mid-2014, if not longer, because the rover will make pit stops at interesting science sites along the way. But far-thinking scientists are already thinking about what areas they would like to examine when it gets there.
One of those is an area that appears to have formed in water. There’s a low ridge on the bottom of the mountain that likely includes hematite, a mineral that other Mars rovers have found. (Remember the “blueberries” spotted a few years ago?) Hematite is an iron mineral that comes to be “in association with water”, a new study reports, and could point the way to the habitable conditions Curiosity is seeking.
The rub is scientists can’t say for sure how the hematite formed until the rover is practically right next to the ridge. There are plenty of pictures from orbit, but not high-resolution enough for the team to make definitive answers.
Colors map percentages of hematite in the surface materials in Meridiani Planum on Mars from 5 percent (aqua) to 25 percent (red). Opportunity landed within the black oval. MER scientists say the rocks there had once been drenched in water. Credit: NASA
“Two alternatives are likely: chemical precipitation within the rocks by underground water that became exposed to an oxidizing environment — or weathering by neutral to slightly acidic water,” wrote Arizona State University’s Red Planet Report. Either way, it shows the ridge likely hosted iron oxidation. Earth’s experience with this type of oxidation shows that it happens “almost exclusively” with microorganisms, but that’s not a guarantee on Mars.
Mars Reconnaissance Orbiter images show that the ridge is about 660 feet (200 meters) wide and four miles (6.5 kilometers) long, with strata or layers in the ridge appearing to be similar to those of layers in Mount Sharp.
While Curiosity is not designed to seek life, it can ferret out details of the environment. Just a few weeks ago, for example, it uncovered pebbles that likely formed in the presence of water. Other Mars missions have also found evidence of that liquid, with perhaps some of it once arising from the subsurface. Where the water came from, and why the environment of Mars changed so much in the last few billion years, are ongoing scientific questions.
