Active Region 1429 unleashed an X5.4-class solar flare early this morning at 00:28 UT, as seen in this image by NASA’s Solar Dynamics Observatory (AIA 304). The eruption belched out a large coronal mass ejection (CME) into space but it’s not yet known exactly how it will impact Earth — it may just be a glancing blow.
Solar flares are categorized by a scale according to their x-ray brightness. X is the strongest class, followed by M and then C-class. Within each class the numbers 1 through 9 subdivide the flares’ intensity.
A run-in with an X5-class flare is a major geomagnetic event that can cause radio blackouts on Earth and disrupt satellite operations, as well as intensify auroral activity.
The GOES satellite data for the March 7 flare is below:
The CME is expected to impact Earth sometime on the 8th or 9th. Check back here or at Spaceweather.com for updates on the storm (and any subsequent aurora photos!)
Also, check out the video below, assembled by the SDO team. Just after the X5.4-class flare another smaller X1-class flare occurred, sending a visible wave cross the Sun.
Image courtesy NASA, SDO and the AIA science team. And thanks to Camilla Corona SDO for all the updates!
An infared image of the cluster. Three narrow slices of the infrared spectrum are represented in this color composite. The colors have been balanced to accentuate the red galaxies at a distance of 10.5 billion light years. Credit: FourStar Galaxy Evolution Survey ("Z-FOURGE")
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Located some 10.5 billion light years away in the general direction of the constellation of Leo, the most distant cluster of red galaxies so far discovered has been hiding in plain sight… until now. Thanks to the advanced observing techniques of FourStar, a new and powerful near-infrared camera on the 6.5m Magellan Baade Telescope, we’re now able to peer beyond faint and into the realm of the faintest. It’s 30 galaxies packed like sardines in a tin and their formation is the earliest known “galaxy city” in the Universe!
“These are the first steps of accurately measuring the rate at which these large urban cities formed in a dark-matter-dominated universe,” says Texas A&M astronomer, Dr. Casey Papovich. “The rate at which they come together tests our understanding of how structures in the universe formed. The broader the timeline, the better our chances of being accurate. Instrumentation is key, and as it evolves, we’ll keep pushing the boundaries.”
Up until now, this galaxy conglomeration had remained undisclosed – despite thousand upon thousands of hours of survey images taken in their area. It is truly amazing that they were overlooked by the huge ground-based telescopes and space-based research instruments, including the Hubble Space Telescope. There was just no accurate distance estimations until the FourStar project came along. Headed by Eric Persson of the Carnegie Observatories, the stellar team includes Carnegie’s David Murphy, Andy Monson, Dan Kelson, Pat McCarthy, and Ryan Quadri – a group whose findings will be published in the Astrophysical Journal Letters.
Just what is FourStar? It’s a specialized camera set with a group of five very specific filters which are sensitively tuned to a very narrow portion of the near-infrared spectrum. “These new filters are a novel approach; it’s a bit like being able to do a CAT scan of the sky to rapidly make a 3-D picture of the early universe,” says Swinburne’s Karl Glazebrook, who is leading the Australian component of the international collaboration formed in 2009.What sets it apart is its ability to accurately measure distances between Earth and target galaxies one at a time. This allows the program to build an incredible three-dimensional look at the source point.
“Most other surveys were just looking at the tip of the iceberg,” Dr. Kim-Vy Tran explains. “The modern technology contained in this camera enabled us to detect the faintest light possible, allowing us to see much more of the iceberg than previously revealed. It’s like we’re using a comb to sift through the very distant universe. The combination of filters and depth provided by this camera give us the equivalent of more teeth, resulting in better measurements and more accurate results.”
The survey was built one deep over an 11×11 arcminute field each in COSMOS, CDFS and UDS. When it comes to galaxy properties, they are looking at 1-2% accurate redshifts and the current 3-D map is looking back to when the Universe was only 3 billion years old.
“This means the galaxy cluster is still young and should continue to grow into an extremely dense structure possibly containing thousands of galaxies,” explained lead author Lee Spitler of Australia’s Swinburne University of Technology.
The FourStar Galaxy Evolution Survey (“Z-FOURGE”) is just the beginning. Through studies of clusters like this one, astronomers can and will get a better understanding of how galaxy clusters evolve in relationship to their environments and – possibly – how they assemble into larger structures. The survey, led by Dr. Ivo Labbé, a former Carnegie postdoctoral fellow, now at Leiden Observatory in the Netherlands, will also strengthen our abilities to determine distances. In just a half a year, the team “has obtained accurate distances for faint galaxies over a region roughly one-fifth the apparent size of the Moon” locating about another thousand galaxies at even further extents.
“The excellent image quality and sensitivity of Magellan and FourStar really make the difference,” Labbé said. “We look forward to many more exciting and unexpected discoveries!”
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
In a 2008 interview by TIME magazine, astrophysicist Neil deGrasse Tyson was asked what he thought the “most astounding fact” about the Universe was. Never at a loss for words, the famed scientist gave his equally astounding answer. His response is in the video above, set to images and music by Max Schlickenmeyer.
It’s the best three minutes and thirty-three seconds you’ll spend all day.
Lake Cuitzeo in central Mexico. (Via Julio Marquez, Wikipedia Commons)
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Exotic sediments found beneath the floor of Lake Cuitzeo in central Mexico support theories of a major cosmic impact event 12,900 years ago, report a 16-member international research team. The impact may have caused widespread environmental changes and contributed to the extinctions of many large animal species.
Images of single and twinned nanodiamonds show the atomic lattice framework of the nanodiamonds. Each dot represents a single atom. (Source: UCSB release.)
The team found a 13,000-year-old layer of sediment that contains materials associated with impact events, such as soot, impact spherules and atomic-scale structures known as nanodiamonds. The nanodiamonds found at Lake Cuitzeo are of a variety known as lonsdaleite, even harder than “regular” diamond and only found naturally as the result of impact events.
The thin layer of sediment below Cuitzeo corresponds to layers of similar age found throughout North America, Greenland and Western Europe.
It’s thought that a large several-hundred-meter-wide asteroid or comet entered Earth’s atmosphere at a shallow angle 12,900 years ago, melting rocks, burning biomass and, in general, causing widespread chaos and destruction. This hypothesized event would have occurred just before a period of unusually cold climate known as the Younger Dryas.
The Younger Dryas has been associated with the extinction of large North American animals such as mammoths, saber-tooth cats and dire wolves.
“The timing of the impact event coincided with the most extraordinary biotic and environmental changes over Mexico and Central America during the last approximately 20,000 years, as recorded by others in several regional lake deposits,” said James Kennett, professor of earth science at UC Santa Barbara and member of the research team. “These changes were large, abrupt, and unprecedented, and had been recorded and identified by earlier investigators as a ‘time of crisis.’ ”
The exotic materials found in the sediment beneath Cuitzeo could not have been created by any volcanic, terrestrial or man-made process. “These materials form only through cosmic impact,” Kennett said.
The only other widespread sedimentary layer ever found to contain such an abundance of nanodiamonds and soot is found at the K-T boundary, 65 million years ago. This, of course, corresponds to the impact event that led to the extinction of the dinosaurs.
The researchers’ findings appeared March 5 in the Proceedings of the National Academy of Sciences. Read the news release from UC Santa Barbara here.
Quantum theory is plenty strange, but one of the strangest discoveries is the realization that there’s a limit to how much you can measure at any one time. This was famously described by Werner Heisenberg, with his uncertainty principle: how you can never know both the position and motion of a particle at the same time.
We record Astronomy Cast live every Monday at 12 pm PST / 3 pm EST / 2000 GMT. If you want to join in our recording, just make sure you’ve got Fraser circled on Google+, then the show will show up in your stream. You can also watch us live at Cosmoquest.
A lunar boulder peeks out into the sunlight. (NASA/GSFC/Arizona State University)
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A lunar boulder catches the last edge of the setting sunlight in this image from the Lunar Reconnaissance Orbiter Camera. The boulders litter the floor of an unnamed 3.5 km wide (2.17 mile wide) crater located within the much larger crater Lobachevskiy. The smaller crater’s rim casts its shadow along the left side of the image, and raises the question: why are shadows on the Moon so dark?
On Earth, air scatters light and allows objects not in direct sunlight to be still well-lit. This is an effect called Rayleigh scattering, named for the British Nobel-winning physicist Lord Rayleigh (John William Strutt.) Rayleigh scattering is the reason why the sky is blue, and (for the most part) why you can still read a magazine perfectly well under an umbrella at the beach.
On the Moon there is no air, no Rayleigh scattering. So shadows are very dark and, where sunlight hits, very bright. Shadowed areas are dramatically murky, like in the LROC image above, yet there’s still some light bouncing around in there — this is due to reflected light from the lunar surface itself.
Buzz was well-lit by reflected light, even in Eagle's shadow. (NASA/Apollo Image Archive)
Lunar regolith is composed of fine, angular particles of very reflective dust. It tends to reflect light directly back at the source, and will illuminate objects within shadows as well — as seen in Apollo mission photographs. Astronauts within the shadow of the landing modules were still visible, and their suits were well illuminated by reflected light from the lunar surface. Some people have used this as “proof” that the landings were actually filmed on a sound stage under artificial lights, but in reality it’s all due to reflected light.
So even though air isn’t scattering the sunlight on the Moon, there’s still enough reflection to sneak light into the shadows… but not much. It gets dark — and quickly cold — in there!
And if you’re one of those who likes to get a better look into the shadows, here’s the same image above with the dark areas brightened enough to see details:
Shadow world revealed! (NASA/GSFC/Arizona State University/J. Major)
Some interesting boulder trails in there!
See this image on Arizona State University’s LROC news page here, and zoom into the full NAC scan here.
A light seen from the International Space Station, intentionally 'flashing' at astronaut Don Pettit. Picture credit: Don Pettit, courtesy of the San Antonio Astronomical Association
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We’ve seen lots of images and videos of city lights on Earth as seen from the International Space Station. But if you were down on Earth, flashing a light at the astronauts on the ISS – would they see you? The answer is now definitively, yes. Flashing the space station with beams of light as it passes overhead had never been successfully done—until this past weekend. Astronomers with the San Antonio Astronomy Association (SAAA) and the Austin Astronomy Society combined forces to flash enough light at the ISS from a dark location, as to appear greater than 0 magnitude to astronaut Don Pettit, on board the station. It turns out, they probably didn’t need the two 800 million lumen searchlights they used, but they sure put on a great show.
“It was amazing,” said Keith Little, from the SAAA. “It was almost like the space station lit up when we shined the lights on it. We had no idea it was going to be that bright.”
Image taken by Don Pettit on the ISS of lights flashing from Texas by the San Antonio Astronomy Association and the Austin Astronomy Society. Credit: Don Pettit, image couresty the SAAA
In a highly coordinated and engineered event, the astronomers flashed the two huge searchlights along with shining a one-watt blue laser at the ISS. Pettit explained some of the preparations in his blog on Fragile Oasis: “This took a number of engineering calculations, Pettit wrote. “Projected beam diameters (assuming the propagation of a Gaussian wave for the laser) and intensity at the target had to be calculated. Tracking space station’s path as it streaked across the sky was another challenge.”
Due to lags in communications to and from the ISS (“on space station we receive email drops two to three times a day,” Pettit said), the whole event took weeks to plan.
The SAAA had an “in” with Pettit, as he is friends with one of their members, astrophotographer and author Robert Reeves, and the idea for doing this was actually hatched before Pettit left for space back in November, 2011.
On March 4, about 65 amateur astronomers were in position at the Lazano Observatory in Springbranch Texas. They turned on the searchlights and waited as the ISS was set to make an appearance in the sky. At the precise time, they began flashing the two searchlights at a rate of two seconds on, then two seconds off, in a very non-technical, but effective manner.
“We had two people manually aiming the lights and two people holding plywood up over the lights, and they were manually tracking the space station,” Little told Universe Today.
Pettit, meanwhile, had no trouble seeing the flashes.
“Don sent us an email the next day,” Little said, “and he told us how bright it was, and how he could see the lights even before we started the flash system. He saw it from 10 degrees above from the west to 10 degrees from the Northeast.”
To everyone’s surprise, Pettit could also see the blue laser. “When the spotlights were off, he said he could still see the blue laser, which was shone steadily,” Little said. “I was pretty surprised that the laser light was that visible from space.”
Little ran the laser and he had three people aiding him by watching for aircraft, “It is an FAA offense to shoot an airplane with a laser, so we took all the safety precautions so that we wouldn’t take that chance,” he said.
But if you see the ISS passing overhead, don’t expect that you can flash a light and they will see it. For one thing, they probably won’t be looking for your light. But additionally, Pettit explained in a previous blog post how when we see the ISS best here on Earth, they can’t see much below.
Ironically, when earthlings can see us, we cannot see them. The glare from the full sun effectively turns our windows into mirrors that return our own ghostly reflection. This often plays out when friends want to flash space station from the ground as it travels overhead. They shine green lasers, xenon strobes, and halogen spotlights at us as we sprint across the sky. These well-wishers don’t know that we cannot see a thing during this time. The best time to try this is during a dark pass when orbital calculations show that we are passing overhead. This becomes complicated when highly collimated light from lasers are used, since the beam diameter at our orbital distance is about one kilometer, and this spot has to be tracking us while in the dark. And of course we have to be looking. As often happens, technical details complicate what seems like a simple observation. So far, all attempts at flashing the space station have failed.
But of course, now there has been a success.
Little said the two astronomy clubs put in 3 months of planning with several meetings, and thanks do the donation of the spotlights from SkyView Searchlights, the costs to do the experiment were minimal. “We had lots of volunteers who wanted to be a part of it,” he said.
Is there any science in this, beyond knowing that under the right conditions the ISS astronauts could see lights from people on Earth?
“Well, if the ISS were to somehow lose all communication, which I would find hard to believe, we just showed that we could spot the station and possibly send them messages through Morse code,” Little said.
But Little said the main thrust of the whole event was the novelty of trying to be the first to successfully shine a light at the ISS that the crew could see, as well as trying to bring astronomy to the attention of the general public.
Apollo 15 landing site imaged from an altitude of 25 km, allowing the highest resolution view from orbit. The Lunar Roving Vehicle (LRV) is parked to the far right, and the Lunar Module descent stage is in the center, LRV tracks indicated with arrows. Credit: NASA/GSFC/Arizona State University.
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A new image from the Lunar Reconnaissance Orbiter’s Narrow Angle Camera provides the most detailed orbital look ever at the Apollo 15 landing site on the Moon. The image of the Hadley plains shows the hardware left behind by astronauts Dave Scott and Jim Irwin and the tracks from the lunar rover.
“We like to look at the Apollo landing site images because it’s fun,” said LRO principal investigator Mark Robinson said at a briefing last year on LRO images. And these latest images are really fun, as look how clearly the lunar lander and the ‘Moon buggy’ show up! (Click images for larger views.) Additionally, we can basically follow all the movements of the rover and the astronauts during their 67-hour stay on the Moon’s surface in August of 1971.
See below for a traverse map of their rover travels.
Apollo 15 traverse routes sketched on an image from LRO. Visible is Hadley Rille. Credit: NASA/GSFC/Arizona State University.
Apollo 15 was the first mission to have the Lunar Rover, which allowed the astronauts to traverse far from the Lunar Module and explore much more local geology than the astronauts on the previous missions (Apollo 11, 12, 14).
“Not only did the LRV allow the astronauts to move from place-to-place at a lively rate of eight to sixteen kilometers per hour (five to ten miles per hour), but the LRV also allowed brief periods of rest that in turn helped to conserve oxygen,” said Robinson on the LROC website.
The goals of Apollo 15 were to sample the basalts in the region, search for ancient crustal rocks and explore a lunar rille for the first time – the long, narrow depressions in the lunar surface that resemble channels. Additionally, Scott and Irwin deployed the third Apollo Lunar Surface Experiments Package (ALSEP), which consisted of several experiments that were powered by a Radioisotope Thermoelectric Generator (RTG) and sent back valuable scientific data to the Earth for over six years after the astronauts left.
Details showing Apollo 15 LRV tracks, see traverse map above for locations. Credit: NASA/GSFC/Arizona State University.
Robinson and his team can figure out the details of what pieces of equipment are in each location by comparing what they see in orbital images to images taken from the surface by the astronauts.
One of the most commonly asked questions is if the flags left on the Moon are still visible.
“All we can really see is the spots where the flag was planted because the astronauts tramped down the regolith,” Robinson said last year. “I’m not sure if the flags still exist, given the extreme heat and cold cycle and the harsh UV environment. The flags were made of nylon, and personally I would be surprised if anything was left of them since it has been over 40 years since they were left on the Moon and the flags we have here on Earth fade after they are left outside for one summer. If the flags are still there they are probably in pretty rough shape.”
For two one-month periods last year (2011), the LRO orbit was lowered such that overflights of the Apollo sites were only 25 to 30 kilometers, rather than the usual 50 kilometers. These low passes resulted in NAC pixel scales near 25 centimeters, Robinson said. “LRO has a ground speed of a bit over 1600 meters (5249 feet) per second, and the shortest NAC exposure time is 0.34 millseconds, so images taken from this low altitude are smeared down track a bit. However, the smear is hardly noticeable and features at the Apollo sites definitely come into sharper focus. In this new low-altitude NAC image of the LRV, tracks are visible about half of the time, usually when the tracks are at an angle to the Sun direction, rather than parallel,” he said.
Top to bottom: Jupiter, Venus and Mercury (just above the horizon), seen at Trusk Lough, Ballybofey County, Donegal Ireland. Credit: Brendan Alexander
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Oh my! What a gorgeous combination of planetary conjunctions and a beautiful landscape! Brendan Alexander (@DonegelSkies) posted this image on our Flickr page, making all our jaws drop at Universe Today. The image wasy taken on March 4, 2012. “When I arrived at Trusk Lough, Ballybofey County, Donegal (Ireland) to try and get a shot of this stunning alignment, a cloud was blocking my view of Mercury,” Brendan wrote on Flickr. “I did manage to get a few shots of all three planets just before Mercury dipped below the horizon.”
Image Details:
Time & Date: 19:30 4th Mar 2012
Equipment: Canon 1000D and Sigma 20mm F1.8 lens
Exposure: 8sec, ISO 200, F1.8 with in camera noise reduction
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