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At this writing, Space shuttle Atlantis’ payload bay doors are closed and everything continues to proceed on schedule for landing.
Click the “play” button to watch NASA TV live right now.
A special landing broadcast is set to begin on Thursday July 21 at 5am EDT/2am PDT/09:00 UTC on the NASA Channel, with landing scheduled at 5:56 EDT/2:56 PDT/09:56 UTC.
This is it, folks.
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Using the Spitzer Space Telescope, a team of astronomers from the National Optical Astronomy Observatory (NOAO) have made a unique discovery. Our neighbor – the Large Magellanic Cloud – has been caught pilfering stars from the Small Magellanic Cloud! What caused this cosmic crime and what do we know about it? Read on…
Through the use of spectra, 5900 giant and supergiant stars in the Large Magellanic Cloud have been identified as once belonging to the nearby Small Magellanic Cloud. NOAO astronomers Knut Olsen and Bob Blum, and their collaborators Dennis Zaritsky (University of Arizona), and Martha Boyer and Karl Gordon (Space Telescope Science Institute) were hot on the trail as they ascertained a counter rotation in a small percentage of the stellar population. Although they could only take information from “line of sight” stars, this 5% was enough to give them a clue they weren’t formed where they are now located. Even their chemical signature isn’t right!
“Further examination of these counter-rotating stars revealed another anomaly. The chemical composition of these stars is different. They have fewer heavy elements such as iron and calcium than typical stars in the Large Magellanic Cloud.” say the team. “However, their composition closely matches that of stars in another nearby galaxy, the Small Magellanic Cloud, whose stars are also depleted in these “metals”.
Just like fingerprints, these two signatures – motion and composition – are a dead giveaway that these certain stars have been lifted by gravitational interaction. To further refine the evidence the group used the multi-object spectrometer on the Cerro Tololo Inter-American Observatory 4-meter Blanco Telescope in Chile to observe 4600 stars, and their spectra, simultaneously. When compared to 1300 other stars, a pattern begin to emerge. According to Olsen “It is not always easy to tell whether the stars in a galaxy formed in the galaxy or formed somewhere else and then were captured. Since the LMC is so close to us, we were able to observe a large number of individual stars. And to our surprise, the LMC contained a significant number of stars that must have formed elsewhere.”
Continuing their investigations with the Spitzer Space Telescope, the team is also involved with stellar evolution studies in the LMC. NOAO Deputy Director Bob Blum indicated the importance of this approach: “Using observations with the Spitzer Space Telescope, we were able to get a complete census of the stellar populations in the LMC. With the ground-based observations we could determine the properties and motions of a large sample of stars throughout that galaxy. By combining both, we were able to tell that some of the stars must have come from the neighboring SMC. This led us to a deeper understanding of how galaxies can and do interact, and change over time.”
These studies may help us to further understand high rates of star formation in areas like 30 Doradus… When we’re not just stealin’ a look.
Original News Source: NOAO News.
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Astronomer and blogger Ian Musgrave from South Australia has been active in debunking the misinformation and nonsense that is being disseminated about Comet Elenin. He has written several wonderful posts featuring the actual realities of this long-period lump of dirty ice that has, for some reason, attracted the attention of doomsdayers, 2012ers, and end-of-the-world scaremongers. Earlier this week, Ian’s Elenin posts on his Astroblog were taken down by the web host, as someone filed a claim for alleged violation of the Digital Millennium Copyright Act (DMCA). “Given that there is no copyrighted material on these pages, with either material generated entirely by me or links to and citation of publicly available material, I believe this was just a frivolous attack on people countering Elenin nonsense” Ian said. Astroblog was not the only site that was targeted, and thankfully, Ian’s web host agreed that the claim was without merit, and the posts are back online. In the interim, however, Universe Today offered to publish Ian’s excellent “Comet Elenin, a FAQ for the Worried” post, and even though the original is now available again, Ian and I decided to still post this on UT so that more people with questions about Comet Elenin would have the chance to have their worries allayed. Have your questions answered below.
Will Comet Elenin Hit Earth?: No, its closest approach is 0.23 AU on Oct 16, 2011, where 1 AU is the distance from the Earth to the Sun. To put this in perspective, this is only a little closer than the closest approach of Venus to Earth, and roughly 100 times the distance from the Earth to the Moon. This distance is from the latest MPEC ephemeris which is based on over 100 observations from multiple observatories that have been continuously tracking the comet, so it won’t change appreciably.
Surely if Elenin Was Going to Hit the Earth NASA/the Government Would Hush it Up? Which government? The Australian Government, the UK Government? The Italian Government? The South African Government? Amateur astronomers world wide are following this comet and continually talking to each other. The have the programs to work out where the comet is going. If the comet was coming anywhere near us, the amateur community would be first to know, and there is no keeping them quite. Consider how wide spread the information is about Apophis, which is a real, if extremely marginal, hazard.
Will it Cause Earthquakes, Abnormally High Tides or Other Disasters: No, Elenin is a mere 3-5 kilometres across and has less than a billionth of the tidal force of the Moon at closest approach (as well as a negligible magnetic field). If the Moon can’t cause the poles to tip, cause massive tidal floods or earthquakes, Comet 2010 X1 Elenin won’t. We’ve been closer to other comets before with no ill effect.
But What About Mensur Omerbashich’s Paper that Says Elenin is Causing Earthquakes? It shows nothing of the sort, earthquakes are no more common during comet alignments than at any other time.
But it’s bigger than Jupiter! No, that’s the coma , the thin haze of gas and dust that surrounds the comet nucleus. The nucleus of C/2010 X1 Elenin is roughly 3-4 Km in diameter and Elenin has a coma around 50,000 km wide at the time of writing (which is a third of the diameter of Jupiter). The average density of the coma is about the same as the density of the atmosphere on the Moon. A coma is a feature of all comets that approach the Sun closely, for example comet 81P Wild (nucleus 4 Km diameter) had a coma of 50,000 Km and 103P Hartley had a coma of 150,000 Km. The Great Comet of 1811 had a nucleus of around 30km in diameter and had a coma nearly as big as the Sun. Comet Halley is 6×15 km and had a coma 100,000 km wide when it last approached Earth. We survived them all (and 103P Hartley came nearly twice as close as Elenin will), and we will survive Elenin without incident.
But I Can See a Picture of it in WikiSky, it’s HUGE! That is the carbon star CW Leonis.
Is Elenin a Moon of a Brown Dwarf Star? No.
But Brown Dwarf Stars are so Cold, you Can’t See Them. No, coldest detected so far is ~370K (about the temperature of a hot cup of tea), the the warmest are around 2200 K, and most range between 500-1000 K. They may not produce much visible light, but they reflect light. Jupiter has a composition similar to those of Brown Dwarf stars. Jupiter’s cloud tops are a chilly 128 K and it reflects light just fine. Any Brown Dwarf in the inner solar system would be painfully obvious.
Will Going Through the Comets Tail Affect Us? No, should the rather small tail of Elenin actually pass over us, it’s doing a pretty good imitation of a vacuum (about 100 atoms per cm3). We have been through bigger and denser comet tails before with no effect whatsoever (especially the Great Comet of 1861).
Why isn’t Comet Elenin in the News? For the same reason that the other 16 comets discovered in 2010 didn’t get in the news, or the 5 comets discovered in 2011. They are all dim. The News is only interested in comets that are spectacular, readily visible to the unaided eye or are being visited by spacecraft. Comet 2009 P1 will be as bright, if not brighter than C/2010 X1 Elenin, but that’s not in the news either. Amateur and professional astronomers are watching comet Elenin and others avidly, but the news channels don’t care about our obsessions with faint fuzzies.
Why Can’t I Find Information of Elenin at the NASA Website? Because NASA is not the arbiter of all things astronomical. You won’t find information on C/2009 P1, C/2011 C1 or any of the faint comets discovered during 2010 and 2011. NASA does have information of comets that its spacecraft have visited, or are interesting in some other way, but it’s not an exhaustive comet site like Cometography or Aerith.
(editor’s note, NASA and JPL’s Near Earth Object Office did publish an article about Comet Elenin in May, 2011, which can be found at this link, confirming it will safely fly past Earth.)
I Saw Comet Elenin Near the Sun in August 2010/Now: In August 2010 only really powerful telescopes could see Elenin. You saw Venus. If you are seeing something bright near the Sun in the morning sky now, it’s Venus.
How Can I Tell What IS in the Sky and Avoid The Venus Confusion? For freeware standalone programs there is Cartes du Ciel and Stellarium (my favourite). For Web based solutions Skyview Cafe, Sky-Map and GoogleEarth (KMZ file here) all work.
Where Can I Find Orbital Elements for Celestia or Stellarium? Here.
Where Can I Find Images of Elenin? Here, and here and a nice image of C/2010 X1 near to NGC 3376 is here.
I have Photographed/ Seen a Photograph of a Double Sun, is this Elenin? It’s lens flare.
Other Good Links:
Leonid Elenin calculates what would happen to planets if a Brown Dwarf was in the inner solar system.
Astronotes, 10 facts you need to know about Elenin.
Astronomy Beat on Elenin (PDF)
See this original post by Ian Musgrave on Astroblog
Those of a certain age can remember watching the footage of the Apollo 11 moonwalk live on television: the view was grainy, shadowy, and dark but it was from the Moon, which trumped everything else. Two years ago for the 40th anniversary of Apollo 11, NASA digitized and re-mastered the original footage, cleaning it up significantly. Here’s a brief montage from all the film that was cleaned up, put together by the Bad Astronomer.
On the road to planetary formation, the first step is an accretion disk around a proto-star. Such disks, known as proplyds, are frequently detected in star forming regions like the Orion nebula providing an understanding of the early life of planetary systems. The telltale hint that they exist is the warm infrared glow of the forming (or perhaps nearly formed) star heating the gas and dust, but although many have been detected this way, few have been observed with resolution that makes out any details on the disk itself. A new study aims to help add to the understanding of these systems with spatially resolved observations of two proplyds, including one already known to be host to a multiple planet system.
The two new systems under study are HD 107146 and HR 8799. The latter of these two systems is notable for having four known planets which have been directly imaged previously. HD 107146 is relatively close to our solar system, being only 28.5 pc away. This young star is similar to the Sun in mass and composition and is estimated to be somewhere between 80 and 200 million years young. Previous studies have examined this system’s disk and revealed that it is composed of nearly as much dust as there is gas, which means that much of the gas has likely been either accreted or stripped. Although not directly detected, the earlier studies have also suggested that the system may be hiding young planets. The evidence for this comes from possible banding in the disk. This is interpreted as similar to the rings and gaps in Saturn’s system, caused by shepherding moons, except in this case, the moon’s role would be fulfilled by planets creating resonances.
The new research, led by Meredith Hughes from the University of California, Berkeley, confirmed the presence of the disk around the star and found its brightness peaked at a distance of about 100 AU from the parent star (more than twice the average orbital distance of Pluto). Overall, their observations match models with a “broad ring extending from 50 to 170 AU”.
When looking at HR 8799’s disk, the team was given four nights, but due to poor weather, only one night’s worth of data from the Submillimeter Array atop Mauna Kea. The reduced amount of data left high uncertainties in the subsequent analysis. While the team attempted to search for banding that could induced by planets, the team was unable to find any. A study published earlier this year by a team at the University of Exeter also examined the HR 8799 disk and reported a slightly brighter clump on one side. The new study finds a similar clump but cautions that, due to the still poor observations of this system, the result may be suspect. A similar case happened when astronomers studied Vega’s dust disk and reported finding clumpy structure when it was, in reality, it was nothing but statistical noise.
These results, as well as the previous ones from the Exeter team and observations from Spitzer have suggested that the dust ring extends out to as far as 250 AU, and as far inwards as 80, but it is likely the inner radius is closer to 150 AU. If the inner radius is the correct value, this places it at roughly the limit that it could be shaped by the outermost planet HR 8799b which lies at just under 70 AU.
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From a Herschel Observatory press release:
Observations with Herschel have revealed unprecedented views of a ring in the centre of our Milky Way galaxy. The ribbon of gas and dust is more than 600 light years across and appears to be twisted, for reasons which have yet to be explained. The origin of the ring could provide insight into the history of the Milky Way.
Professor Bruce Swinyard of the Rutherford Appleton Laboratory said “Herschel’s detectors are ideally suited to see through the dust lying between us and the center of our galaxy, and to find the relatively cold material, at only 15 degrees above absolute zero, which we have learned makes up the ring.” The new results are published in a recent issue of the Astrophysical Journal Letters.
Warmer gas and dust from the center of our galaxy is shown in blue in the above image, while the colder material appears red. The ring, in yellow, is made of gas and dust at a temperature of just 15 degrees above absolute zero. The bright regions are denser, and include some of the most massive and active sites of star formation in our galaxy.
“Hints of this feature were seen in previous images of the Galactic Centre made from the ground, but no-one realised what it was,” explained Dr. Mark Thompson of the University of Hertfordshire. “It was not until the launch of Herschel, with its unparalleled wavelength coverage, that we could measure the temperature of the dust clouds and determine its true nature.”
The central region of our galaxy is dominated by a bar-like structure, which stirs up the material in the outer galaxy as it rotates over millions of years and is thought to be responsible for its spiral structure. The ring seen by Herschel lies right in the middle of this bar, encircling the region which harbors a super-massive black hole at the center of our galaxy. Professor Glenn White of The Open University and The Rutherford Appleton Laboratory said that “although bars have been seen in other galaxies, this ring of cold material revealed by Herschel, and the way it twists around the Galactic Centre, were completely unexpected, revealing several surprises.”
Firstly, the ring of gas is twisted, so from our vantage point we see two loops which appear to meet in the middle. These are seen in yellow in the image above, tilted slightly such that they run from top-left to bottom-right. Secondly, it seems to be slightly offset from the very center of our Galaxy, where a super-massive black hole lurks. “This is what is so exciting about launching a new space telescope like Herschel,” said Sergio Molinari of the Institute of Space Physics in Rome, Italy, lead author of the new paper. “We have a new and exciting mystery on our hands, right at the center of our own galaxy.”
The reason for the ring’s twist and offset are unknown, but understanding their origin may help explain the origin of the ring itself. Computer simulations indicate that bars and rings such as those we see in the center of our galaxy can be formed by gravitational interactions. It is possible that the structures in the heart of the Milky Way were caused by interactions with our largest neighbor, the Andromeda Galaxy.
“Like all good science experiments, Herschel is creating as many questions as it answers”, said Professor Matt Griffin, of the University of Cardiff, and Principle Investigator on one of Herschel’s detectors used in this study. “Unravelling the mystery of this ring could help us to explore the processes which have taken place deep in the heart of our Galaxy over billions of years.”
See the “twist” in Chromoscope or Google Sky.
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Astronomers using the Hubble Space Telescope discovered a fourth moon orbiting the icy dwarf planet Pluto. The tiny, new satellite – temporarily designated P4 — was uncovered in a Hubble survey searching for rings around the dwarf planet.
The new moon is the smallest discovered around Pluto. It has an estimated diameter of 8 to 21 miles (13 to 34 km). By comparison, Charon, Pluto’s largest moon, is 648 miles (1,043 km) across, and the other moons, Nix and Hydra, are in the range of 20 to 70 miles in diameter (32 to 113 km).
“I find it remarkable that Hubble’s cameras enabled us to see such a tiny object so clearly from a distance of more than 3 billion miles (5 billion km),” said Mark Showalter of the SETI Institute in Mountain View, Calif., who led this observing program with Hubble.
The finding is a result of ongoing work to support NASA’s New Horizons mission, scheduled to fly through the Pluto system in 2015. The mission is designed to provide new insights about worlds at the edge of our solar system. Hubble’s mapping of Pluto’s surface and discovery of its satellites have been invaluable to planning for New Horizons’ close encounter.
“This is a fantastic discovery,” said New Horizons’ principal investigator Alan Stern of the Southwest Research Institute in Boulder, Colo. “Now that we know there’s another moon in the Pluto system, we can plan close-up observations of it during our flyby.”
The new moon is located between the orbits of Nix and Hydra, which Hubble discovered in 2005. Charon was discovered in 1978 at the U.S. Naval Observatory and first resolved using Hubble in 1990 as a separate body from Pluto.
The dwarf planet’s entire moon system is believed to have formed by a collision between Pluto and another planet-sized body early in the history of the solar system. The smashup flung material that coalesced into the family of satellites observed around Pluto.
Lunar rocks returned to Earth from the Apollo missions led to the theory that our moon was the result of a similar collision between Earth and a Mars-sized body 4.4 billion years ago. Scientists believe material blasted off Pluto’s moons by micrometeoroid impacts may form rings around the dwarf planet, but the Hubble photographs have not detected any so far.
“This surprising observation is a powerful reminder of Hubble’s ability as a general purpose astronomical observatory to make astounding, unintended discoveries,” said Jon Morse, astrophysics division director at NASA Headquarters in Washington.
P4 was first seen in a photo taken with Hubble’s Wide Field Camera 3 on June 28. It was confirmed in subsequent Hubble pictures taken on July 3 and July 18. The moon was not seen in earlier Hubble images because the exposure times were shorter. There is a chance it appeared as a very faint smudge in 2006 images, but was overlooked because it was obscured.
For more images and information, see the HubbleSite.
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Through the Wormhole with Morgan Freeman has entered into its second season and is working to highlight topics as physical as space flight and as metaphysical as whether or not we have a sixth sense. The show is hosted by Academy Award-winner Morgan Freeman and airs on Wednesday nights on the Science Channel. This week’s show deals with a subject that many space flight enthusiasts have wondered for some time – can we really travel faster than the speed of light?
If the universe has a speed limit – it is considered to be the speed of light – at least we think it is the limit. Ever since Albert Einstein introduced us to the Theory of Relativity – we have been seeking ways if not to break this limit – then at least to bend it – a lot. For according to Einstein – it is impossible for humans to go faster than light. Scientists working in laboratories across the globe are trying to prove Einstein wrong – but can they? Time will tell and Through the Wormhole will take a peek at their efforts.
The show tackling the question of light speed will air on Wednesday, July 20, 2011 at 10 p.m. EDT.
It turns out that Freeman himself has often pondered many of the questions raised on the show and he wanted to share his wonder with the rest of world.
“My love affair with science and the unknown began for me in my high school physics class,” said Freeman. “My mind sprung open – all because of the questions I asked. In this new season of Through the Wormhole, we will explore ten new mystifying questions that will change the way you look at the world around you.”
Morgan Freeman and Lori McCreary are executive producers for Revelations Entertainment which produces the show. As mentioned, the show is entering its second season; this was confirmed in February of this year. The show was conceived as utilizing an element of pop culture (in this case Morgan Freeman, a celebrity, as the show’s narrator) with deep questions that have confronted mankind, in some cases since the dawn of time. By all accounts the show has been very successful.
The crew of STS-135 are now on the homestretch of their mission. At 2:28 a.m. EDT Tuesday, space shuttle Atlantis undocked from the International Space Station while the spacecraft were 243 miles above the Pacific. Atlantis spent eight days, 15 hours and 21 minutes docked to the ISS.
Atlantis is scheduled to make its first attempt to land at NASA’s Kennedy Space Center on Thursday, July 21, at 5:56 a.m. EDT.
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In the weeks leading up to the launch of Space Shuttle Atlantis, I had the distinct honor to speak on several occasions with Chris Ferguson, the Space Shuttle Commander of the STS-135 mission that will soon close out NASA’s Space Shuttle Era.
Chris talked to me about his childhood experiences that led him to “love science” and how he strongly believes in “giving back” to a community that enriched him so much – and eventually led him to his career as a space shuttle astronaut.
That passion for science and giving will result in an extraordinary and out of this world gift to the people of Philadelphia, Pennsylvania, hometown to Chris Ferguson that he hopes will inspire kids to love science.
I first met Chris about two years ago in Philadelphia when he generously gave a well received presentation to our astronomy club, the Rittenhouse Astronomical Society – which meets at the Franklin Institute Science Museum and where I frequently lecture too.
At that time Ferguson had already been a veteran space flyer with two trips to the International Space Station – but he not yet been named to command the last shuttle flight. Over 150 folks attended Ferguson’s talk – held in the presence of the marble statue of Benjamin Franklin. The statue is a US National Historic Landmark.
As a child, Chris attended classes from grade school to high school in Philadelphia, the city of brotherly love.
“I developed and cultivated a love of science, engineering and space in many childhood trips to the Franklin Institute in Philadelphia,” Ferguson told me.
“I was always a science oriented kid growing up. I have an innate curiosity for how things work. The Franklin Institute fed my curiosity.”
“And it was some teachers I had at a young age in my high school in Philadelphia who made me want to understand more. And to understand the reason about why things work the way they do … And to understand why the physical laws that govern the Universe are the way they are.”
“The one thing I could never fathom well was understanding spaceflight. And the way to really understand something is to go do it,” said Chris Ferguson.
“What this is really about is going into space, living and working there and dragging the American public along with us. We need to constantly feed the machine for the folks who are curious and are on a quest to understand things they don’t understand and desire to wonder what’s beyond low Earth orbit and how you live in space for a long period of time.”
“The only way you feed that is by planting the seeds when they are young. You grow the big Oaks out of little acorns.”
“And you get the little acorns at places like the Franklin Institute and the Smithsonian National Air & Space Museum. That’s what did it for me,”
“I think you need to go back and you need to give back. So I’m looking forward to going back to the Franklin Institute !” said Ferguson
And when Chris does go back to the Franklin Institute later this year he will bring along a very very special gift – a piece of the Institute’s Fels Planetarium dome flew millions of miles to the space station and back aboard history’s very last Space Shuttle orbiter – Atlantis – that will ever take a star trek to the High Frontier.
And the project was Ferguson’s idea according to Derrick Pitts, Chief Astronomer at the Fels Planetarium of the Franklin Institute.
“Chris sent me an email asking if we (The Franklin Institute) would like to fly something on STS-135,” Pitts told me.
“I quickly agreed, found out what the criteria for launch would be and then pulled a team together to figure out what to send. It was decided to send a star-shaped piece of the original Fels Planetarium dome.
“The original dome was replaced in 2002 but I’d kept several large sections of the stainless steel panels and had a number of 5-pointed stars about 4″ across cut from the panels to mount and give as gifts to friends of the Fels. It weighs about 6 oz.”
“Since more than 10 million visitors have sat under that dome including several school students who would later become NASA astronauts, it seemed fitting to send one of these stars.”
“The piece presented some problems though. As a stainless steel piece, it has sharp edges and 5 very sharp points – both verboten by NASA and it is ever so slightly oversized. We fixed the worst problem by encasing the star – points edges and all – in a transparent acrylic ‘jewel box’ sandwich held closed with stainless steel screws.”
“We had about ten days from the first email to delivery date to him in Houston. When it returns to Earth, Ferguson has offered to bring it back to Philadelphia where we’ll put it on permanent display in the main Planetarium hallway. This will be the second time Franklin has flown an article with a native Philadelphian astronaut. Our last trip was with Jim Bagian on STS-40 in 1991.”
Chris is a humble, eloquent and down to earth guy and knows how lucky he is to be commanding the grand finale of the thirty year long shuttle program. And he is determined that he and his STS-135 crew of four do their very best to accomplish all their goals.
“I’m just proud to be a small part of it and am savoring the moment. We’re focused on the mission now and will have time to ponder this moment in history when it’s all over,” Ferguson concluded.
Space Shuttle Atlantis and her crew of 4 are scheduled to land at 5:56 a.m. on July 21, 2011 at the Kennedy Space Center in Florida.
Read my features about the Final Shuttle mission, STS-135:
Revolutionary Robotic Refueling Experiment Opens New Research Avenues at Space Station
Water Cannon Salute trumpets recovery of Last Shuttle Solid Rocket Boosters – Photo Album
Shuttle Atlantis Soars to Space One Last time: Photo Album
Atlantis Unveiled for Historic Final Flight amidst Stormy Weather
Counting down to the Last Shuttle; Stormy weather projected
Atlantis Crew Jets to Florida on Independence Day for Final Shuttle Blastoff
NASA Sets July 8 for Mandatory Space Shuttle Grand Finale
Final Shuttle Voyagers Conduct Countdown Practice at Florida Launch Pad
Final Payload for Final Shuttle Flight Delivered to the Launch Pad
Last Ever Shuttle Journeys out to the Launch Pad; Photo Gallery
Atlantis Goes Vertical for the Last Time
Atlantis Rolls to Vehicle Assembly Building with Final Space Shuttle Crew for July 8 Blastoff</a