Satellite image of RI and portions of southeastern Massachusetts. Credit: NASA/GSFC/Landsat 7
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If you live in or are from the US, you probably know that today is Super Bowl Sunday. Whatever you happen to be doing, be it tailgating in Indianapolis, getting together with friends and family (and plenty of hot wings and nachos) in your living room or just waiting for all the fuss to be over, remember that, high above, NASA Earth-observing satellites are working hard doing what they do best: observing the Earth. Chances are they’ve imaged your home town many times.
Whichever team you’re rooting for, here’s a little bit of space science fun: the folks over at Goddard Space Flight Center in Greenbelt, MD, have shared some Landsat images of the home cities of this year’s big game.
The image above shows the central and northern RI and southeastern Massachusetts area, with Providence and Pawtucket seen as the densely-built central region and Foxborough, MA, where the Patriots’ home stadium is located, is just to the north of the image. This image was acquired by Landsat 7 in July 2002.
(Being of my home state, I admit I’m partial to that particular shot. I was down there somewhere!)
The NYC area seen from satellite. Credit: NASA/GSFC/Landsat 7
If you’re a die-hard Giants fan, you may recognize this area… you may even be in it! It’s a Landsat 7 image of the New York metro area acquired on August 8, 2002. Manhattan is in the center, most easily recognizable from space by the green rectangle of Central Park. New Jersey is on the left side, and Brooklyn on the center-right with Long Island stretching away to the east.
Indianapolis from Landsat 7 satellite. Credit: NASA/GSFC/Landsat 7
If you’re lucky enough to have tickets to the big game, you may be here: it’s a Landsat image of Indianapolis, IN acquired on July 11, 2001. The Colts may not have made it this year but right now the city is definitely “ready for some football!”
Of course, team and town loyalty aside, this gorgeous image from Expedition 30 crew members aboard the ISS shows everyone all in one place on the night of January 29, 2012 – with a nice touch of northern lights thrown in for good measure:
US East Coast on Jan. 29, 2012. (NASA)
Bright lights, big cities… but a small world, when you think about it. And remember, whichever team comes out on top today, tomorrow we’re all winners. (Until next season, of course!)
Earth's eastern hemisphere made from Suomi NPP satellite images. (NASA/NOAA)
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In response to last week’s incredibly popular “Blue Marble” image, NASA and NOAA have released a companion version, this one showing part of our planet’s eastern hemisphere.
The image is a composite, made from six separate high-resolution scans taken on January 23 by NASA’s recently-renamed Suomi NPP satellite.
Compiled by NASA Goddard scientist Norman Kuring, this image has the perspective of a viewer looking down from 7,918 miles (about 12,742 kilometers) above the Earth’s surface from a viewpoint of 10 degrees South by 45 degrees East. The four vertical lines of ‘haze’ visible in this image shows the reflection of sunlight off the ocean, or ‘glint,’ that VIIRS captured as it orbited the globe. Suomi NPP is the result of a partnership between NASA, NOAA and the Department of Defense.
Last week’s “Blue Marble” image is now one of the most-viewed images of all time on Flickr, receiving nearly 3.2 million views!
NASA launched the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (or NPP) on October 28, 2011 from Vandenberg Air Force Base. On Jan. 24, NPP was renamed Suomi National Polar-orbiting Partnership, or Suomi NPP, in honor of the late Verner E. Suomi. It’s the first satellite designed to collect data to improve short-term weather forecasts and increase understanding of long-term climate change.
Image credit: NASA/NOAA
Added: check out a “zoomified” version of this image on John Williams’ StarryCritters site.
This is going to be one of the “how we know what we know” kind of shows. How do scientist determine the age of things? How do we know the age of everything from stone tools, to the age of the Earth, to the age of the very Universe.
You can watch us record Astronomy Cast live every Monday at 12:00 pm PDT (3:00 pm EDT, 2000 GMT). Make sure you circle Fraser on Google+ to see it show up in the feed. You can also see it live over on our YouTube channel.
If you’d like to be notified of all our live events, sign up for our notification email at Cosmoquest. You can check out our calendar here.
First Ever Portrait of the International Space Station and docked Shuttle Endeavour from Soyuz capsule. This image of the International Space Station and the docked Space Shuttle Endeavour, flying at an altitude of 220 miles was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on May 23, 2011. It is the first-ever image of a space shuttle docked to the International Space Station. Endeavour at left. European ATV cargo carrier at right. Credit: NASA/Paolo Nespoli
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2011 was a picturesque year! The year brought us new discoveries, a new supernova, the end of an era in human spaceflight, and much more. Here’s a look back at some of the best images we’ve posted on Universe Today in 2011, listed in no particular order:
Above, is one of the first-ever images of a space shuttle docked to the International Space Station. The images were taken by ESA astronaut Paolo Nespoli on May 23, 2011 through a window inside the Soyuz TMA-20 vehicle as he and two crewmates were departing the ISS for their return trip to Earth. See the entire gallery of images of this event here.
Supernova PTF11kly in M101. Credit: Rick Johnson
A new supernova showed up in 2011 in the Pinwheel galaxy, and skywatchers around the world tried to capture it. Amateur astronomer Rick Johnson submitted this image for our new “Astrophoto” feature this year on Universe Today. Called the SN PTF11kly, the new Type Ia supernova was spotted by Caltech’s Palomar Transient Factory (PTF) survey in the M101, and is located 21 million light years away. You can see the supernova marked in the southern part of the galaxy.
Atlantis launches one last time on July 8, 2011. Credit: Alan Walters (awaltersphoto.com) for Universe Today.
2011 saw the end of an era: the space shuttle program is now history. Universe Today photographer Alan Walters captured this stunning view of the last shuttle launch ever. Read our articles about the final launch and landing of the space shuttle era.
A portion of the Lagoon nebula imaged by the Gemini South telescope with the Gemini Multi-Object Spectrograph. Credit: Julia I. Arias and Rodolfo H. Barbá Departamento de Física, Universidad de La Serena (Chile), and ICATE-CONICET (Argentina).
A gorgeous new look at the “Southern Cliff” in the Lagoon Nebula from the Gemini South Observatory.
Saturns moons and rings, in color. Credit: NASA / JPL / SSI. Edited by Jason Major. Click for larger version.
The Cassini spacecraft continues to crank out spectacular images, and this stunning image of a “flash mob” of moons strung along Saturn’s rings is just an example.
ATV2 (Johannes Kepler) as it departs the ISS against the backdrop of Earth. Credit: NASA/Ron Garan
Real image or from a movie? The ATV-2 Johannes Kepler looks like an X-Wing fighter from Star Wars as it departed from the International Space Station.
A new image from the HiRISE camera on the Mars Reconnaissance Orbiter shows an ethereal landscape near Mars north pole. Credit: NASA/HiRISE team
Incredible landscapes are specialties of the HiRISE camera on the Mars Reconnaissance Orbiter, and this observation shows dune gullies laced with beautiful swirls of tracks left by dust devils. Just like on Earth, dust devils move across the Martian surface and expose the underlying darker material, creating a striking view.
A new image from ESO of the reflection nebula Messier 78. Credit: ESO and Igor Chekalin
Here’s a “Hidden Treasure” from the European Southern Observatory, from the astrophotography competition where amateurs create images from unused ESO data. In this new image of Messier 78, brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light and creating what is called a reflection nebula.
Series of transits taken on May 20, 22 and 23, 2011 from different areas of France, showing variations of orientation of the ISS with Endeavour docked. On May 23, the ISS passes besides a sunspot which is larger than the Earth. Credit: Thierry Legault
This series of images is just an example of the great work by award-winning French astrophotographer Thierry Legault. During shuttle Endeavour’s final mission, Legault traveled through Germany, France and Spain to find clear skies and good seeing to capture the shuttle’s voyage to the International Space Station. See more incredible images here.
The 'Rock Garden' at the rim of Endeavour Crater on Mars as seen by the Opportunity rover. Credit: NASA/JPL/Caltech, color by Stu Atkinson
The Opportunity rover is now exploring Endeavour Crater and this color view of shows a stunning landscape on Mars. This view of a Red Planet “rock garden” is the colorized handiwork of Stu Atkinson, a member of Unmanned Spaceflight and author of the Road to Endeavour blog. This is actually an ejecta field of rocks thrown about after the impact that created this huge crater, and has been an exciting region for the MER scientists to explore.
Dense filaments of gas in the IC5146 interstellar cloud. This image was taken by ESA’s Herschel space observatory at infrared wavelengths 70, 250 and 500 microns. Stars are forming along these filaments. Credits: ESA/Herschel/SPIRE/PACS/D. Arzoumanian (CEA Saclay) for the “Gould Belt survey” Key Programme Consortium.
Its true there is no sound in empty interstellar space, but the Herschel space observatory has observed the cosmic equivalent of sonic booms. Filaments like this have been sighted before by other infrared satellites, but they have never been seen clearly enough to have their widths measure.
A huge and spectacular prominence eruption on the Sun, June 7, 2011. Credit: NASA/Solar Dynamics Observatory
On June 7, 2011 an amazingly massive and spectacular event took place on the Sun: a huge prominence eruption, marked by a solar flare and release of energetic particles. It was an event that was heretofore unseen on the Sun, but the Solar Dynamics Observatory saw it all.
A view of a recent aurora from the ISS. Credit: NASA
With the Sun’s activities ramping up, we saw more aurorae. What better place to see them than from the International Space Station? This view taken by astroanut Mike Fossum shows a stunning aurora, with two Russian vehicles docked to the station in the foreground.
The star cluster NGC 2100 in the Large Magellanic Cloud. Credit: ESO
A brilliant cluster of stars in the Large Magellanic Cloud, open cluster NGC 2100 shines brightly, competing with the nearby Tarantula Nebula for bragging rights in this image from ESO’s New Technology Telescope (NTT).
Martian Vista from Opportunity nearing Endeavour Crater on Sol 2678 - August 2011 Large ejecta blocks from the nearby, small Odyssey crater are visible in the middle, foreground and are Opportunity’s next science target in this photo mosaic taken 2 martian days ago on Sol 2678 (Aug. 6). Opportunity is now less than 400 feet from the foothills of Endeavour Crater and will soon make first landfall at Spirit Point - off to the left. At Endeavour, Opportunity will investigate the oldest minerals deposits she has ever visited from billions of years ago and which may hold clues to environments that were potentially habitable for microbial life. This photo mosaic shows portions of the discontinuous crater rim – Cape Tribulation at right. Mosaic Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Kenneth Kremer
Universe Today’s Ken Kremer helped bring this stunning image of the hills around Endeavour Crater to light, as the Opportunity Rover headed towards the crater in August.
X-ray Image of Tycho's Supernova Remnant. (NASA/CXC/Rutgers/K.Eriksen et al.)
The Chandra X-Ray Observatory took a brand new, deep look inside the Tycho Supernova Remnant, providing a nearly three-dimensional view of the iconic space object.
The aurora australis seen from the ISS on September 17, 2011. Credit: NASA.
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With all of the activity that’s been occurring on the Sun recently, the aurorae have been exceptionally bright and have created quite a show to viewers – both on Earth as well as above it!
The image above was taken over the southern Indian Ocean by astronauts aboard the International Space Station. The southern lights – a.k.a. aurora australis – glow bright green and red in the upper layers of the atmosphere, creating a dazzling aerial display. (Click here to watch a movie of this.)
Shortly after, fires can be seen on the ground as the ISS passes over Australia:
Wildfires in Australia seen from orbit. Credit: NASA.
Astronauts on the International Space Station (ISS) used a digital camera to capture several hundred photographs of the aurora australis, or “southern lights,” while passing over the Indian Ocean on September 17, 2011. You can see the flowing ribbons and rays below as the ISS passed from south of Madagascar to just north of Australia between 17:22 and 17:45 Universal Time. Solar panels and other sections of the ISS fill some of the upper right side of the photograph.
Auroras are a spectacular sign that our planet is electrically and magnetically connected to the Sun. These light shows are provoked by energy from the Sun and fueled by electrically charged particles trapped in Earth’s magnetic field, or magnetosphere. In this case, the space around Earth was stirred up by an explosion of hot, ionized gas from the Sun — a coronal mass ejection — that left the Sun on September 14, 2011.
In the second image above, and in the last frames of the movie, light from the ground replaces the light show in the sky. Wildfires and perhaps some intentionally set agricultural fires burn on the continent of Australia,with smoke plumes faintly visible in the night sky. A gold and green halo of atmospheric airglow hangs above the horizon in the distance.
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Airglow is created by particles in the upper atmosphere that have been charged by UV light from the Sun during the day releasing the energy at night as greenish-yellow visible light.
Fires on the ground, fires in the sky… the stars blazing all around, the Sun in its full glory and a never-ending view of our entire planet… what an incredible place the ISS must be to work in! Absolutely amazing!
And the skies of night were alive with light, with a throbbing, thrilling flame; Amber and rose and violet, opal and gold it came. It swept the sky like a giant scythe, it quivered back to a wedge; Argently bright, it cleft the night with a wavy golden edge.
— “The Ballad of the Northern Lights”, Robert Service
It starts out innocently enough: a small speck against a field of background stars, barely noticeable in the image data. But… it’s a speck that wasn’t there before. Subsequent images confirm its existence – there’s something out there. Something bright, something large, and it’s moving through our solar system very quickly. The faint blur indicates that it’s a comet, an icy visitor from the outermost reaches of the solar system. And it’s headed straight toward Earth.
Exhaustive calculations are run and re-run. Computer simulations are executed. All possibilities are taken into consideration, and yet there’s no alternative to be found; our world will face a close encounter with a comet in mere months’ time. Phone calls are made, a flurry of electronic messages fly between computer terminals across the world, consultations are held with top experts in the field. We are unprepared… what can we do? What does this mean for civilization as we know it? What will this speeding icy bullet from outer space do to our planet?
The answer? Nothing.
Nothing at all. In fact, it probably won’t even be very interesting to look at – if you can even find it when it passes by.
(Sorry for the let-down.)
There’s been a lot of buzz in the past several months regarding Comet Elenin, a.k.a. C/2010 X1, which was discovered by Russian astronomer Leonid Elenin on December 10, 2010. Elenin spotted the comet using a telescope in New Mexico remotely from his location in Lyubertsy, Russia. At that time it was about 647 million kilometers (401 million miles) from Earth… in the time since it has closed the distance considerably, and is now around 270 million km away. Elenin is a long-period comet, which means it has a rather large orbit around the Sun… it comes in from a vast distance, swings around the Sun and heads back out to the depths of the solar system – a round trip lasting over 10,000 years. During its current trip it will pass by Earth on October 16, coming as close as 35 million km (22 million miles).
Elenin's orbit via the JPL Small-Body Database Browser
Yes, 22 million miles.
That’s pretty far.
Way too far for us to be affected by anything a comet has to offer. Especially a not-particularly-large comet like Elenin.
Some of the doomy-gloomy internet sites have been mentioning the size of Elenin as being 80,000 km across. This is a scary, exaggerated number that may be referring to the size of Elenin’s coma – a hazy cloud of icy particles that surrounds a much, much smaller nucleus. The coma can be extensive but is insubstantial; it’s akin to icy cigarette smoke. Less than that, in fact… a comet’s coma and tail are even more of a vacuum than can be reproduced in a lab on Earth! In reality most comets have a nucleus smaller than 10km…that’s less than a billionth the mass of Earth (and a far cry from 80,000 km.) We have no reason to think that Elenin is any larger than this – it’s most likely smaller.
Ok, but how about the gravitational and/or magnetic effect of a comet passing by Earth? That’s surely got to do something, right? To Earth’s crust, or the tides? For the answer to that, I will refer to Don Yeomans, a researcher at NASA’s Near-Earth Object Program Office at JPL:
“Comet Elenin will not only be far away, it is also on the small side for comets. And comets are not the most densely-packed objects out there. They usually have the density of something akin to loosely packed icy dirt,” said Yeomans. “So you’ve got a modest-sized icy dirtball that is getting no closer than 35 million kilometers. It will have an immeasurably miniscule influence on our planet. By comparison, my subcompact automobile exerts a greater influence on the ocean’s tides than comet Elenin ever will.”
“It will have an immeasurably miniscule influence on our planet. By comparison, my subcompact automobile exerts a greater influence on the ocean’s tides than comet Elenin ever will.”
– Don Yeomans, NASA / JPL
And as far as the effect from Elenin’s magnetic field goes… well, there is no effect. Elenin, like all comets, doesn’t have a magnetic field. Not much else to say there.
But the claims surrounding Elenin have gone much further toward the absurd. That it’s going to encounter another object and change course to one that will cause it to impact Earth, or that it’s not a comet at all but actually a planet – Nibiru, perhaps? – and is on a collision course with our own. Or (and I particularly like this one) that alien spaceships are trailing Elenin in such a way as to remain undetected until it’s too late and then they’ll take over Earth, stealing our water and natural resources and turning us all into slaves and/or space munchies… or however the stories go. (Of course the government and NASA and Al Gore and Al Gore’s hamster are all in cahoots and are withholding this information from the rest of us. That’s a given.) These stories are all just that – stories – and have not a shred of science to them, other than a heaping dose of science fiction.
“We live in nervous times, and conspiracy theories and predictions of disaster are more popular than ever. I like to use the word cosmophobia for this growing fear of astronomical objects and phenomena, which periodically runs amuck on the Internet. Ironically, in pre-scientific times, comets were often thought to be harbingers of disaster, mostly because they seemed to arrive unpredictably – unlike the movements of the planets and stars, which could be tracked on a daily and yearly basis.”
– David Morrison, planetary astronomer and senior scientist at NASA’s Ames Research Center
The bottom line is this: Comet C/2010 X1 Elenin is coming, and it will pass by Earth at an extremely safe distance – 100 times the distance from Earth to the Moon. It will not be changing direction between now and then, it will not exert any gravitational effect on Earth, its magnetic field is nonexistent and there are no Star Destroyers cruising in its wake. The biggest effect it will have on Earth is what we are able to learn about it as it passes – after all, it is a visitor from the far reaches of our solar system and we won’t be seeing it again for a very, very long time.
I’m sure we’ll have found something else to be worried about long before then.
“This intrepid little traveler will offer astronomers a chance to study a relatively young comet that came here from well beyond our solar system’s planetary region. After a short while, it will be headed back out again, and we will not see or hear from Elenin for thousands of years. That’s pretty cool.”
– Don Yeomans
For more information about Elenin, check out this JPL news release featuring Don Yeomans, and there’s a special public issue of Astronomy Beat, a newsletter from the Astronomical Society of the Pacific, that features David Morrison of NASA’s Ames Research Center discussing many of the misconceptions about Elenin.
An updated chart of Elenin’s orbit and statistics can be viewed here.
As a part of NASA’s ongoing Year of the Solar System – which is actually a single Martian year long, or 23 months – the excitement of planetary exploration is being brought to people around the world through a enthusiastic science outreach program called From Earth to the Solar System (FETTSS). A continuation of the well-received International Year of Astronomy 2009 From Earth to the Universe program, FETTSS provides over 90 beautiful high-resolution images of fascinating locations around our solar system; from the ice geysers of Enceladus to the plasma arcs of solar prominences, the cold dunes of Mars to the hot springs of Yellowstone, the FETTSS collection showcases many wonders of many worlds – and helps bring them within view of as many people as possible.
The images are displayed in public locations, hosted by organizations that raise all the necessary funding to have them printed and installed. The FETTSS site exists to provide the high-resolution print images as well as offer guidance as to how to best plan, market and set up an installation.
What’s wonderful about From Earth to the Solar System – as well as its predecessor From Earth to the Universe – is how it brings the fascination of science and astronomy to people who may not have previously given it much thought. By presenting large-format images with descriptive captions in common places – such as in an airport or outside in a public park – FETTSS hosts are actively capturing the interest of viewers and engaging them in astronomy – many undoubtedly for the first time.
People around the world are being connected with the most recent work of scientists and researchers in a way that’s attractive, informative and yet accessible. This is the key to any successful outreach program.
The images are at once artistic and informative, weaving together themes in astrobiology, planetary science, and astronomy. Including contributions from backyard astronomers, large telescopes in space, and even point-and-shoot cameras of field researchers, the collection represents the current state of exploration as seen through the eyes of the scientific community.
Currently an exhibit is just wrapping up in Corpus Christi, Texas, at the Museum of Science and History and was very well-received by both people and the press! The next scheduled event will take place in June at the National Air and Space Museum in Washington, DC.
A FETTU outdoor installation in Geneva
FETTSS looks to build on the success of the 2009 FETTU program.
“We are hoping to replicate some of FETTU’s success and bring a measure of sustainability to the FETTU concept. ‘From Earth to the Solar System’ is taking a similar grassroots-type of approach to exhibit creation, and will hopefully help remove the barrier to ‘seeking science out’ for some visitors and help make setting up an exhibit more efficient for organizers,” said Kimberly Kowal Arcand, Media Production Coordinator for the Harvard-Smithsonian Center for Astrophysics and FETTSS principal investigator.
“With FETTU – and what we hope to find with FETTSS – there was a wonderful response from both visitors and organizers,” said Arcand. “We found, unexpectedly, a sort of emotional and personal connection to the images in the FETTU project and I’m interested to see if we find that again with FETTSS. I was personally overwhelmed with the response to FETTU… it was the most inspiring thing I have ever worked on!”
Already, exhibitors worldwide have expressed interest in hosting FETTSS installations… from Argentina, Serbia, China, Colombia, Canada, UK, Ireland, Egypt, Spain, Armenia, as well as from numerous locations in the US – many of whom had previously hosted FETTU events.
So with such a great program and strong response, the question remains: what’s next?
“From Earth to the Sun? From Earth to the Galaxies?” suggested Arcand.
With all that’s being discovered, whatever it is it’s sure to be another success!
For more information about FETTSS or to host an FETTSS event in your area, visit the main site here.
Artist concept of matter swirling around a black hole. (NASA/Dana Berry/SkyWorks Digital)
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Imagine a spinning black hole so colossal and so powerful that it kicks photons, the basic units of light, and sends them careening thousands of light years through space. Some of the photons make it to Earth. Scientists are announcing in the journal NaturePhysics today that those well-traveled photons still carry the signature of that colossal jolt, as a distortion in the way they move. The disruption is like a long-distance missive from the black hole itself, containing information about its size and the speed of its spin.
The researchers say the jostled photons are key to unraveling the theory that predicts black holes in the first place.
“It is rare in general-relativity research that a new phenomenon is discovered that allows us to test the theory further,” says Martin Bojowald, a Penn State physics professor and author of a News & Views article that accompanies the study.
Black holes are so gravitationally powerful that they distort nearby matter and even space and time. Called framedragging, the phenomenon can be detected by sensitive gyroscopes on satellites, Bojowald notes.
Lead study author Fabrizio Tamburini, an astronomer at the University of Padova (Padua) in Italy, and his colleagues have calculated that rotating spacetime can impart to light an intrinsic form of orbital angular momentum distinct from its spin. The authors suggest visualizing this as non-planar wavefronts of this twisted light like a cylindrical spiral staircase, centered around the light beam.
“The intensity pattern of twisted light transverse to the beam shows a dark spot in the middle — where no one would walk on the staircase — surrounded by concentric circles,” they write. “The twisting of a pure [orbital angular momentum] mode can be seen in interference patterns.” They say researchers need between 10,000 and 100,000 photons to piece a black hole’s story together.
And telescopes need some kind of 3D (or holographic) vision in order to see the corkscrews in the light waves they receive, Bojowald said: “If a telescope can zoom in sufficiently closely, one can be sure that all 10,000-100,000 photons come from the accretion disk rather than from other stars farther away. So the magnification of the telescope will be a crucial factor.”
He believes, based on a rough calculation, that “a star like the sun as far away as the center of the Milky Way would have to be observed for less than a year. So it is not going to be a direct image, but one would not have to wait very long.”
Study co-author Bo Thidé, a professor and program director at the Swedish Institute of Space Physics, said a year may be conservative, even in the case of a small rotation and a need for up to 100,000 photons.
“But who knows,” he said. “We will know more after we have made further detailed modelling – and observations, of course. At this time we emphasize the discovery of a
new general relativity phenomenon that allows us to make observations, leaving precise quantitative predictions aside.”
Opportunity arrived at ‘Intrepid’ Crater on Mars during November 2010 and drove around crater rim. See rover wheel tracks at left. Intrepid crater was named in honor of the Apollo 12 lunar module named “Intrepid” – which landed two men on the moon on 19 November 1969. This false color mosaic was assembled from pancam images taken by Opportunity on Sol 2420 (Nov 14, 2010). Mosaic Credit: Kenneth Kremer, Marco Di Lorenzo NASA/JPL/Cornell
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NASA recently celebrated the anniversary of the historic Apollo 12 lunar landing mission with another history making craft – the long lived Opportunity Mars rover. Opportunity traversed around and photographed ‘Intrepid’ crater on Mars in mid November 2010. The crater is informally named in honor of the ‘Intrepid’ lunar module which landed two humans on the surface of the moon on 19 November 1969, some forty one years ago.
Apollo 12 was only the second of NASA’s Apollo missions to place humans on the Earth’s moon. Apollo astronauts Pete Conrad and Gordon Bean precisely piloted their lunar landing spacecraft nicknamed ‘Intrepid’ to a safe touchdown in the ‘Ocean of Storms’, a mere 180 meters (600 feet) away from the Surveyor 3 robotic lunar probe which had already landed on the moon in April 1967. The unmanned Surveyor landers paved the way for NASA’s manned Apollo landers.
As Conrad and Bean walked on the moon and collected lunar rocks for science, the third member of the Apollo 12 crew, astronaut Dick Gordon, orbited alone in the ‘Yankee Clipper’ command module and collected valuable science data from overhead.
On the anniversary of the lunar landing, the rover science team decided to honor the Apollo 12 mission as Opportunity was driving east and chanced upon a field of small impact craters located in between vast Martian dune fields. Informal crater names are assigned by the team to craters spotted by Opportunity in the Meridiani Planum region based on the names of historic ships of exploration.
Opportunity rover took first panorama of Intrepid crater on Sol 2417 (Nov.11, 2010) which shows the rim of distant Endeavour crater in the background. Mosaic Credit: NASA/JPL/Cornell
Rover science team member James Rice, of NASA’s Goddard Space Flight Center, Greenbelt, Md., suggested using names from Apollo 12 because of the coincidental timing according to NASA. “The Apollo missions were so inspiring when I was young, I remember all the dates. When we were approaching these craters, I realized we were getting close to the Nov. 19 anniversary for Apollo 12,” Rice said. He sent Bean and Gordon photographs that Opportunity took of the two craters named for the two Apollo 12 spaceships.
Bean wrote back the following message to the Mars Exploration Rover team: “I just talked with Dick Gordon about the wonderful honor you have bestowed upon our Apollo 12 spacecraft. Forty-one years ago today, we were approaching the moon in Yankee Clipper with Intrepid in tow. We were excited to have the opportunity to perform some important exploration of a place in the universe other than planet Earth where humans had not gone before. We were anxious to give it our best effort. You and your team have that same opportunity. Give it your best effort.”
On November 4, Opportunity drove by and imaged ‘Yankee Clipper’ crater. After driving several more days she reached ‘Intrepid’ on November 9. The rover then traversed around the crater rim and photographed the crater interior from different vantage points, collecting two panoramic views along the way.
Opportunity soon departed Intrepid on Sol 2420 (Nov. 14) to resume her multi-year trek eastwards and took a series of crater images that day – from a very different direction – which we were inspired to assemble into a panoramic mosaic (in false color) in tribute to the Apollo 12 mission (see above).
Our mosaic tribute clearly shows the rover wheel tracks as Opportunity first approached Intrepid on Nov. 9 – which is fittingly reminiscent of the Apollo 12 astronauts walking on the moon 41 years ago as they explored a lunar crater. By comparison, the arrival mosaic from Sol 2417 shows distant Endeavour crater in the background.
Intrepid crater is about 16 meters in diameter, thus similar in size to ‘Eagle’ crater inside which Opportunity first landed on 24 January 2004 after a 250 million mile ‘hole in one shot’ from Earth. Eagle was named in honor of the Apollo 11 mission.
“Intrepid is fairly eroded with sand filling the interior and ejecta blocks planed off by the saltating sand”, said Matt Golembek, Mars Exploration Program Landing Site Scientist at the Jet Propulsion Laboratory (JPL), Pasadena, Calif. Asked about the age of Intrepid crater, Golembek told me; “Based on the erosional state it is at least several million years old, but less than around 20 million years old.”
Opportunity is blazing ahead towards a huge 22 km (14 mile) wide crater named ‘Endeavour’, which shows distinct signatures of clays and past wet environments based on orbital imagery thus making the crater a compelling science target.
“Intrepid is 1.5 km from Santa Maria crater and about 7.5 km from Endeavour.”
“We should be at Santa Maria crater next week, where we will spend the holidays and conjunction. Then it will be 6 km to Endeavour,” Golembek said.
The road ahead looks to be alot friendlier to the intrepid rover. “The terrain Opportunity is on is among the smoothest and easiest to traverse since Eagle and Endurance. Should be smooth sailing to Endeavour, averaging about 100 meters per drive sol. We should easily beat MSL to the phyllosilicates,” Golembek explained.
Phyllosilicates are clay minerals that form under wet, warm, non-acidic conditions. They have never before been studied on the Martian surface.
MSL is the Mars Science Lab, NASA’s next Mars lander mission and which is scheduled to blast off towards the end of 2011. Golembek leads the landing site selection team.
The amazing Opportunity rover has spent nearly seven years roving the Martian surface, conducting a crater tour during her very unexpectedly long journey at ‘Meridiani Planum’ on Mars which now exceeds 26 km (16 miles). The rovers were designed with a prime mission “warranty” of just 90 Martian days – or sols – and have vastly exceeded their creators expectations.
“What a ride. This still does not seem real,” Rob Manning told me. Manning headed the Entry, Descent and Landing team at JPL for both the Spirit and Opportunity rovers. “That would be fantastic if Opportunity could get to the phyllosilicates before MSL launches.”
Stay tuned.
This map of the region around NASA's Mars Exploration Rover Opportunity shows the relative locations of several craters and the rover location in May 2010. Credit: NASA/JPL-Caltech/Malin Space Science Systems/WUSTLAS12-48-7133 (20 Nov. 1969) --- This unusual photograph, taken during the second Apollo 12 extravehicular activity (EVA), shows two U.S. spacecraft on the surface of the moon. The Apollo 12 Lunar Module (LM) is in the background. The unmanned Surveyor 3 spacecraft is in the foreground. The Apollo 12 LM, with astronauts Charles Conrad Jr. and Alan L. Bean aboard, landed about 600 feet from Surveyor 3 in the Ocean of Storms. The television camera and several other pieces were taken from Surveyor 3 and brought back to Earth for scientific examination. Here, Conrad examines the Surveyor's TV camera prior to detaching it. Astronaut Richard F. Gordon Jr. remained with the Apollo 12 Command and Service Modules (CSM) in lunar orbit while Conrad and Bean descended in the LM to explore the moon. Surveyor 3 soft-landed on the moon on April 19, 1967.
There are few things in astronomy more awe inspiring and spellbinding than the birth of a star. Even though we now understand how they are formed, the sheer magnitude of it is still enough to stir the imagination of even the most schooled and cynical academics. Still, there is some degree of guesswork and chance when it comes to where stars will be born and what kind of stars they will become. For example, while some stars are single field stars (like our Sun), others form in groups of two (binary) or more, sometimes much more. This is what is known as a Star Cluster, by definition, a group of stars that share a common origin and are gravitationally bound for some length of time.
Thereare two basic categories of star clusters: Globular and Open (aka. Galactic) star clusters. Globular clusters are roughly spherical groupings of stars that range from 10,000 to several million stars packed into regions ranging from 10 to 30 light years across. They commonly consist of very old Population II stars – which are just a few hundred million years younger than the universe itself – and are mostly yellow and red. Open clusters, on the other hand, are very different. Unlike the spherically distributed globulars, open clusters are confined to the galactic plane and are almost always found within the spiral arms of galaxies. They are generally made up of young stars, up to a few tens of millions of years old, with a few rare exceptions that are as old as a few billion years. Open clusters also contain only a few hundred members within a region of up to about 30 light-years. Being much less densely populated than globular clusters, they are much less tightly gravitationally bound, and over time, will become disrupted by the gravity of giant molecular clouds and other clusters.
Star clusters are particularly useful to astronomers as they provide a way to study and model stellar evolution and ages. By estimating the age of globular clusters, scientists were able to get a more accurate picture of how old the universe is, putting it at roughly 13 billion years of age. In addition, the location of star clusters and galaxies is believed to be a good indication of the physics of the early universe. This is based on aspects of the Big Bang theory where it is believed that immediately after the creation event, following a period of relatively homogenous distribution; cosmic matter slowly gravitated to areas of higher concentration. In this way, star clusters and the position of galaxies provide an indication of where matter was more densely distributed when the universe was still young.
Some popular examples of star clusters, many of which are visible to the naked eye, include Pleiades, Hyades, the Beehive Cluster and the star nursery within the Orion Nebula.
