Dextre, a large robotic manipulator to help with outside maintenence of the ISS was added in October of 2007. Credit: NASA
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Ten years ago, the first Expedition crew arrived at the International Space Station. Here’s a look back in time at how the station has changed and grown, and some of the people who were there to make it happen.
The configuration of the ISS when the first expedition crew arrived on Nov. 2, 2000. Credit: NASA
Expedition Two crewmembers Yury Usachev (left), mission commander, Jim Voss, flight engineer, and Susan Helms, flight engineer, share a dessert in the Zvezda Service Module. Credit: NASAThis image was taken on April 21, 2001 during Expedition 2; the first large solar arrays were added during the STS-100 space shuttle mission. Credit: NASAThe Expedition Five crewmembers in the Destiny laboratory on the ISS. From the left are cosmonaut Valery Korzun, mission commander; astronaut Peggy A. Whitson, who became the ISS’s first science officer, and cosmonaut Sergei Treschev. Credit: NASAThe Microgravity Science Glovebox was added to the Destiny lab on the ISS during Expedition 5. Credit: NASAThe Expedition Six crew pose for a crew photo in the Zarya module on the ISS; Don Pettit (front), science officer; cosmonaut Nikolai Budarin (left back), flight engineer; and astronaut Ken Bowersox, mission commander. Credit: NASADuring Expedition 6, the space shuttle Columbia accident occurred, and the shuttle program was on hold. ISS astronauts Don Pettit (left) and Ken Bowersox had to do a variety of maintenance tasks outside the ISS that normally visiting shuttle crews would have taken care. Credit: NASA.It was rather lonely times for awhile on the ISS -- with no space shuttles flying, only two crewmembers were able to be on board the ISS. Here are Expedition 7's Yuri Malenchenko and Ed Lu. Credit: NASAThe Russian Soyuz vehicle serves as transportation and rescue vehicle for the ISS. Credit: NASANew Crew member? No, this is the European Matroshka-R Phantom experiment, which operated during Expedition 12 in the Zvezda Service Module of the International Space Station. Matroshka, the name for the traditional Russian set of nestling dolls, is an antroph-amorphous model of a human torso designed for radiation studies. Credit: NASAStuff happens it space. During a spacewalk, Expedition 16 commander Fyodor Yurchikhin noticed damage to a multi-layer insulation (MLI) protective blanket on the Zarya module. The damage, he noted, was apparently from a micrometeoroid impact. The date the damage occurred is unknown but has had no impact to vehicle operations. Credit: NASA Shuttles returned to flight in July of 2005, and this is how the ISS looked when space shuttle Discovery visited, the first shuttle visit in over 2 years. Credit: NASAThe ISS as it looked in June of 2007, during the STS-117 mission. Credit: NASAThe backbone of the ISS is the huge truss, brought up to the ISS in smaller segments, which are still huge by themselves. Dave Williams, STS-118 mission specialist from Canada works outside the ISS, helping to attach the Starboard 5 (S5) segment, and works on the forward heat-rejecting radiator from the station's Port 6 (P6) truss. Credit: NASAA look inside the Harmony node that was brought to the ISS in on the STS-120 mission in 2007. Credit: NASSunita Williams, Expedition 15 flight engineer, works on a science experiment in April of 2007. Credit: NASABackdropped by the thin line of Earth's atmosphere and the blackness of space, a portion of the International Space Station is featured in this image photographed by an Expedition 20 crew member aboard the station. in May 2009. Credit: NASAA torn solar array panel in the ISS, which was installed during the STS-120 mission. See below for the repair job. Credit: NASAThe repaired solar array, fixed by STS-120 astronauts. Credit: NASAEuropean Space Agency (ESA) astronaut Hans Schlegel, STS-122 mission specialist, works on the new Columbus laboratory that was installed in February 2008. Credit: NASAAstronauts work on adding the Japanese logistics module-pressurized section in March of 2008 during the STS-123 mission. Credit: NASADextre, a large robotic manipulator to help with outside maintenence of the ISS was added in October of 2007. Credit: NASAA motley-looking crew of the Expedition 17 and 18 crewmembers in the Harmony node in Oct. 2008. Credit: NASAHere's how the ISS looked durng the STS-128 mission in September of 2009. Credit: NASADuring the STS-130 mission in Feb. 2010, the Cupola and Tranquility Node were added. The Cupola provides unprecidented views of Earth and space from the ISS. Credit: NASAHow the ISS looked during the STS-130 mission in February 2010. Credit: NASAThe Russian Mini Research Module was added in May of 2010 on STS-132. Credit: NASANASA astronauts Shannon Walker (left), Expedition 24/25 flight engineer; Tracy Caldwell Dyson, Expedition 23/24 flight engineer; and Doug Wheelock, Expedition 24 flight engineer and Expedition 25 commander, pose for photo in the Poisk Mini-Research Module 2 (MRM2) of the International Space Station. How the ISS looks today (as of this writing), and as it looked following the STS-132 mission in May of 2010. Credit: NASA
Ten years ago today US astronaut Bill Shepherd and Russian cosmonauts Sergei Krikalev and Yuri Gidzenko arrived at the fledgling International Space Station, after launching in a Soyuz rocket from the Baikonur Cosmodrome in Kazakhstan on October 31, 2000. This began a decade of continuous human habituation on board the station. The station’s first commander reflects on his mission and the past 10 years.
A halo appeared around the Sun on Nov. 1, 2010 in Centurion South Africa. Credit: Alan Buff.
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Residents around Johannesburg, South Africa were treated with a rare astronomical (or actually atmospheric) sight — a halo around the Sun. These halos are striking to see, but unlike an eclipse, they can’t be predicted. Conditions in the atmosphere have to be just right, with moisture or ice crystals creating a “rainbow” effect around the Sun. Sometimes the halos surround the Sun completely, other times, they appear as arcs around the solar sphere. Basically, sunlight is reflecting off moisture in the atmosphere. These images were sent in by Alan Buff from Centurion, South Africa. See more below.
Another image of a halo that appeared around the Sun on Nov. 1, 2010 in Centurion South Africa; this one has a building blocking out the Sun itself. Credit: Alan Buff.
In folklore, these halos seen around the Sun or the Moon means precipitation is on the way, which makes sense, since moisture in the atmosphere usually makes it down to the ground. High clouds of ice crystals are called cirrus clouds, and these often form in at the leading edge of warm fronts that bring rain.
Newspaper and internet articles report that Johannesburg was buzzing about the weird halos; however, the explanation was simple and did not include aliens or end-of-the-world scenarios.
A halo appeared around the Sun on Nov. 1, 2010 in Centurion South Africa. Credit: Alan Buff.
Thanks again to Alan Buff for sharing his images with Universe Today.
The Bad Astronomer posted a time-lapse video today which is wonderful, and you should go watch it, but I’m going to counter with another incredible time-lapse that might be even better (in my opinion! — and as suggested by Daniel Fischer on Twitter). This one was created by photographer Dustin Farrell, and shows a year’s compilation of his time lapse work. “All shot on the Canon 5D2 and processed in Adobe After Effects,” Farrell writes on his Vimeo page. “The majority of the shots are in my beautiful home state of Arizona. Goblin Valley State Park and Natural Bridges National Monument in Utah also make an appearance,” — as do NASA’s new electric rovers. Check out Farrell’s company’s website, CrewWest, Inc.
Screenshot from the Gigapan image of space shuttle Discovery on the launchpad.
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From experience, I can tell you being at one of the launchpads at Kennedy Space Center is awesome beyond words. Not many people, though, get to see a shuttle on the launchpad up close and personal, and with just a couple launches left, many are at least are hoping to get a view of the launch. But if you aren’t able to travel to Florida and see a shuttle on the pad, you can take advantage of a few different websites that can take you there virtually, and probably bring you closer than you could ever get in person.
The first website is Gigapan, where NASA photographer Bill Ingalls has put together all the high resolution images he took on Sunday, Oct. 31, 2010 at Kennedy Space Center, and created one huge images that you can pan around and see everything up close. Go to the Gigapan website, and by moving your mouse around or by clicking on the images below the big image, you will be transported up close and personal with various locations within the image.
The Gigapan technology was originally developed for the Mars Exploration Rovers, and the panoramas created from Mars enabled a simulated experience of being on another planet. The Gigapan project aims to create a similar experience, but for exploration of Earth.
The second website is John O’Connor’s NASA Tech website. I met John when I was at Kennedy Space Center earlier this year, was able to watch him take the images for the extremely high resolution virtual tours he creates. The interactive 360 degree images he creates are nothing short of stunning — but they are also very bandwidth intensive — so be prepared, and watch out if you don’t have high speed internet or have a lot of browsers or windows open on your computer. Right now on his website you can see different views of the launchpad with Discovery sitting on top, and also go inside the space station processing facility and see Robonaut 2 before he was stowed for launch on STS-133, and much more.
Here’s an image I took of John setting up his equipment when we were at Launchpad 39B in March of this year.
Vertical structures, among the tallest seen in Saturn's main rings, rise abruptly from the edge of Saturn's B ring to cast long shadows on the ring in this image taken by NASA's Cassini spacecraft in 2009.
It has long been known that Saturn’s rings are not the perfect hoops they appear as in small amateur telescopes, and when the Cassini spacecraft entered orbit around Saturn, the wonky disorder of the massive B ring became even more apparent. Scientists were stunned by towering vertical structures, scalloped edges on the rings, and odd propeller-like features. But scientists have now found the cause of these strange features: The region is acting just like a spiral galaxy, said Carolyn Porco, team lead of the Cassini imaging team.
“We have found what we hoped we’d find when we set out on this journey with Cassini nearly 13 years ago,” said Porco, “(and have gotten) visibility into the mechanisms that have sculpted not only Saturn’s rings, but celestial disks of a far grander scale, from solar systems, like our own, all the way to the giant spiral galaxies.”
The B ring is one of the most dynamic areas in Saturn’s rings, and surprisingly, scientists say, the rings are behaving like a miniature version of our own Milky Way galaxy.
When the the Voyager spacecraft flew by Saturn in 1980 and 1981, scientists saw that the outer edge of the planet’s B ring was shaped like a rotating, flattened football by the gravitational perturbations of Mimas. But it was clear, even in Voyager’s findings, that the outer B ring’s behavior was far more complex than anything Mimas alone might do.
Vertical Structures Tower over Saturn’s B-Ring. This image was rendered using Autodesk Maya and Adobe Photoshop. Credit: Kevin Gill.
Through the analysis of thousands of Cassini images of the B ring taken over a four-year period, Porco and her team have found the source of most of the complexity: at least three additional, independently rotating wave patterns, or oscillations, that distort the B ring’s edge.
The oscillations travel around the ring with differing speeds and the small, random motions of the ring particles feed energy into a wave that propagates outward across the ring from an inner boundary, reflects off the outer edge of the B ring (which becomes distorted as a result), and then travels inward until it reflects off the inner boundary. This continuous back-and-forth reflection is necessary for these wave patterns to grow and become visible as distortions in the outer edge of the B ring.
These oscillations, with one, two or three lobes, are not created by any moons. They have instead spontaneously arisen, in part because the ring is dense enough, and the B ring edge is sharp enough, for waves to grow on their own and then reflect at the edge.
The ring particles’ small, random motions feed energy into a wave and cause it to grow. The new results confirm a Voyager-era predication that this same process can explain all the puzzling chaotic waveforms found in Saturn’s densest rings, from tens of meters up to hundreds of kilometers wide.
“This process has already been verified to produce wave features in Saturn’s dense rings that are of small scale…about 150 meters or so,” Porco wrote in her “Captain’s Log” feature on the CICLOPS (Cassini imaging)website. “That it now also appears to produce waves of large, hundreds-of-kilometers scale in the outer B ring suggests that it can operate in dense rings on all spatial scales.”
“These oscillations exist for the same reason that guitar strings have natural modes of oscillation, which can be excited when plucked or otherwise disturbed,” said Joseph Spitale, Cassini imaging team associate and lead author of a new article in the Astronomical Journal, published today. “The ring, too, has its own natural oscillation frequencies, and that’s what we’re observing.”
Astronomers believe such “self-excited” oscillations exist in other disk systems, like spiral disk galaxies and proto-planetary disks found around nearby stars, but they have not been able to directly confirm their existence. The new observations confirm the first large-scale wave oscillations of this type in a broad disk of material anywhere in nature.
Self-excited waves on small, 100-meter (300-foot) scales have been previously observed by Cassini instruments in a few dense ring regions and have been attributed to a process called “viscous overstability.”
Oscillations in Saturn's B ring. Credit: Space Science Institute
“Normally viscosity, or resistance to flow, damps waves — the way sound waves traveling through the air would die out,” said Peter Goldreich, a planetary ring theorist at the California Institute of Technology. “But the new findings show that, in the densest parts of Saturn’s rings, viscosity actually amplifies waves, explaining mysterious grooves first seen in images taken by the Voyager spacecraft.”
“How satisfying it is to find at last one explanation for most, if not all, of the chaotic looking structure we first saw in Saturn’s dense ring regions long ago with Voyager,” said Porco, “and have since seen in exquisite detail with Cassini.”
Proctor Crater Dune Field on Mars. Credit: NASA/JPL/University of Arizona
I just got lost on Mars. I saw this intriguing image, above, on the HiRISE camera website, and ended up spending a large chunk of my morning just wandering through the dunes of Mars — actually wandering through images of dunes on Mars. These striking features have to be one of the most intriguing areas of study on the Red Planet since they are one of the most dynamic geologic processes going on currently on Mars.
The dark dunes are composed of basaltic sand, and scientists believe the dunes in the image above have formed in response to fall and winter westerly winds. Also superimposed on their surface are smaller secondary dunes that are commonly seen on terrestrial dunes of this size.
See below for more intriguing dunes on Mars that I came across in my wanderings…
North Polar Dunes. Credit: NASA/JPL/University of Arizona.Chocolate dunes? Credit: NASA/JPL/University of ArizonaDunes and Layered Bedrock on Floor of Large Crater in Xanthe Terra. Credit: NASA/JPL/University of ArizonaSeasonal Frost on Dunes. Credit: NASA/JPL/University of ArizonaDune Symmetry. Credit: NASA/JPL/University of ArizonaMartian Barchan Dunes. Credit: NASA/JPL/University of ArizonaFalling Material Kicks Up Cloud of Dust on Dunes. Credit: NASA/JPL/University of Arizona
We’ve posted this image before, as it really is a weird-looking landscape, but it is worth seeing again.
Polar Sand Dunes. Credit: NASA/JPL/University of Arizona
The white dwarf G29-38. Many stars, including our Sun, end their lives as white dwarfs. Determining the masses of white dwarf stars is key to the new technique of determining a star's age. Image Credit: NASA
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While supernovae are the most dramatic death of stars, 95% of stars will end their lives in a far more quiet fashion, first swelling up to a red giant (perhaps a few times for good measure) before slowly releasing their outer layers into a planetary nebula and fading away as a white dwarf. This is the fate of our own sun which will expand nearly to the orbit of Mars. Mercury, Venus, and Earth will be completely consumed. But what will happen to the rest of the planets in the system?
While many stories have suggested that as the star reaches the red giant phase, even before swallowing the Earth, the inner planets will become inhospitable while the habitable zone will expand to the outer planets, perhaps making the now frozen moons of Jupiter the ideal beach getaway. However, these situations routinely only consider planets with unchanging orbits. As the star loses mass, orbits will change. Those close in will experience drag due to the increased density of released gas. Those further out will be spared but will have orbits that slowly expand as the mass interior to their orbit is shed. Planets at different radii will feel the combination of these effects in different ways causing their orbits to change in ways unrelated to one another.
This general shaking up of the orbital system will result in the system becoming once again, dynamically “young”, with planets migrating and interacting much as they would when the system was first forming. The possible close interactions can potentially crash planets together, fling them out of the system, into looping elliptical orbits, or worse, into the star itself. But can evidence of these planets be found?
A recent review paper explores the possibility. Due to convection in the white dwarf, heavy elements are quickly dragged to lower layers of the star removing traces of elements other than hydrogen and helium in the spectra. Thus, should heavy elements be detected, it would be evidence of ongoing accretion either from the interstellar medium or from a source of circumstellar material. The author of the review lists two early examples of white dwarfs with atmospheres polluted in this respect: van Maanen 2 and G29-38. The spectra of both show strong absorption lines due to calcium while the latter has also had a dust disk detected around the star?
But is this dust disk a remnant of a planet? Not necessarily. Although the material could be larger objects, such as asteroids, smaller dust sized grains would be swept from the solar system due to radiation pressure from the star during the main sequence lifetime. Much like planets, the asteroids orbits would be perturbed and any passing too close to the star could be torn apart tidally and pollute the star as well, albeit on a much smaller scale than a digested planet. Also along these lines is the potential disruption of a potential Oort cloud. Some estimates have predicted that a planet similar to Jupiter may have it’s orbit expanded as much as a thousand times, which would likely scatter many into the star as well.
The key to sorting these sources out may again lie with spectroscopy. While asteroids and comets could certainly contribute to the pollution of the white dwarf, the strength of the spectral lines would be an indirect indicator of the averaged rate of absorption and should be higher for planets. Additionally, the ratio of various elements may help constrain where the consumed body formed in the system. Although astronomers have found numerous gaseous planets in tight orbits around their host stars, it is suspected that these formed further out where temperatures would allow for the gas to condense before being swept away. Objects formed closer in would likely be more rocky in nature and if consumed, their contribution to the spectra would be shifted towards heavier elements.
With the launch of the Spitzer telescope, dust disks indicative of interactions have been found around numerous white dwarfs and improving spectral observations have indicated that a significant number of systems appear polluted. “If one attributes all metal-polluted white dwarfs to rocky debris, then the fraction of terrestrial planetary systems that survive post-main sequence evolution (at least in part) is as high as 20% to 30%”. However, with consideration for other sources of pollution, the number drops to a few percent. Hopefully, as observations progress, astronomers will begin to discover more planets around stars between the main sequence and white dwarf region to better explore this phase of planetary evolution.
Why is the sunset red? Awesome question. The most basic answer is that light is refracted by particles in the atmosphere and the red end of the spectrum is what is visible. To better understand that you have to have a basic understanding of how light behaves in the air, the atmosphere’s composition, the color of light, wavelengths, and Rayleigh scattering and here is all of the information that you need to understand those things.
The Earth’s atmosphere is one of the main factors in determining what color a sunset is. The atmosphere is made up mostly of gases with a few other molecules thrown in. Since it completely surrounds the Earth it affects what you see in every direction. The most common gasses in our atmosphere are nitrogen(78%) and oxygen(21%). The remaining single percent is made up of trace gasses, like argon, and water vapor and many small solid particles, like dust, soot and ashes, pollen, and salt from the oceans. There may be more water in the air after a rainstorm, or near the ocean. Volcanoes can put large amounts of dust particles high into the atmosphere. Pollution can add different gases or dust and soot.
Next, you have to look at light waves and the color of light. Light is an energy that travels in waves. Light is a wave of vibrating electric and magnetic fields and is a part of the electromagnetic spectrum. Electromagnetic waves travel through space at the speed of light(299,792 km/sec). The energy of the radiation depends on its wavelength and frequency. A wavelength is the distance between the tops of the waves. The frequency is the number of waves that pass by each second. The longer the wavelength of the light, the lower the frequency, and the less energy it contains. Visible light is the part of the electromagnetic spectrum that our eyes can see. Light from a light bulb or the Sun may look white, but it is actually a combination of many colors. Light can be split into its different colors with a prism. A rainbow is a natural prism effect. The colors of the spectrum blend into one another. The colors have different wavelengths, frequencies, and energies. Violet has the shortest wavelength meaning that it has the highest frequency and energy. Red has the longest wavelength and lowest frequency and energy.
In order to put it all together, we have to look at the action of light in the air of our planet. Light moves in a straight line until it is interfered with(gas molecule, dust, or anything else). What happens to that light depends on the wavelength of the light and size of the particle. Dust particles and water droplets are much larger than the wavelength of visible light, so it bounces off in different directions. The reflected light appears white because it still contains all of the same colors, but gas molecules are smaller than the wavelength of visible light. When light bumps into them it acts differently. After light hits a gas molecule some of it may get absorbed. Later, the molecule radiates the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the colors can be absorbed, but the higher frequencies (blues) are absorbed more often than the lower frequencies (reds). This process is called Rayleigh scattering.
Long story short,, the answer to ‘why is the sunset red?’ is: At sunset, light must travel farther through the atmosphere before it gets to you, so more of it is reflected and scattered and the sun appears dimmer. The color of the sun itself appears to change, first to orange and then to red because even more of the short wavelength blues and greens are now scattered and only the longer wavelengths(reds, oranges) are left to be seen.
We have written many articles about the sunset for Universe Today. Here’s an article about sunrise and sunset, and here are some sunset pictures.
This volcanic cone in the Nili Patera caldera on Mars has hydrothermal mineral deposits on the southern flanks and nearby terrains. Two of the largest deposits are marked by arrows, and the entire field of light-toned material on the left of the cone is hydrothermal deposits. Image Credit: NASA/JPL-Caltech/MSSS/JHU-APL/Brown Univ.
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Evidence of a past “hot spring” environment on Mars has shown up in images from the Mars Reconnaissance Orbiter. Scientists say light-colored mounds of hydrated silica on the side of a volcano are likely deposits from steam fumaroles, or hot springs, which may have provided a habitable environment on the Red Planet about three billion years ago. Concentrations of hydrated silica have been identified on Mars previously, including an ancient hot springs environment that the Spirit rover stumbled across in 2007.
“The heat and water required to create this deposit probably made this a habitable zone,” said J.R. Skok from Brown University, lead author of a paper about these findings published online today by Nature Geoscience. “If life did exist there, this would be a promising type of deposit to entomb evidence of it — a microbial mortuary.”
While it is not direct evidence of life on Mars, it adds to the mounting evidence of past habitable environments for at least microbial life on the planet, and is the most intact ancient hot springs region ever found. This specific spot in the Syrtis Major volcanic region on Mars would have been hospitable to life when most of Mars was already dry and cold.
Skok said, “You have spectacular context for this deposit. It’s right on the flank of a volcano. The setting remains essentially the same as it was when the silica was deposited.”
The small cone rises about 100 meters (100 yards) from the floor of a shallow volcanic caldera named Nili Patera and covers about 50 kilometers (30 miles) of Syrtis Major, which is near Mars equator. The collapse of an underground magma chamber from which lava had emanated created the bowl, and subsequent lave flows tell a story of how the cone formed.
“We can read a series of chapters in this history book and know that the cone grew from the last gasp of a giant volcanic system,” said John Mustard, Skok’s thesis advisor at Brown and a co-author of the paper. “The cooling and solidification of most of the magma concentrated its silica and water content.”
Orbital images revealed patches of bright deposits near the summit of the cone, fanning down its flank, and on flatter ground in the vicinity. The Brown researchers partnered with Scott Murchie of Johns Hopkins University Applied Physics Laboratory, Laurel, Md., to analyze the bright exposures with the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument on the orbiter.
Silica can be dissolved, transported and concentrated by hot water or steam. Hydrated silica identified by the spectrometer in uphill locations — confirmed by stereo imaging — indicates that hot springs or fumaroles fed by underground heating created these deposits. Silica deposits around hydrothermal vents in Iceland are among the best parallels on Earth.
Murchie said, “The habitable zone would have been within and alongside the conduits carrying the heated water.” The volcanic activity that built the cone in Nili Patera appears to have happened more recently than the 3.7-billion-year or greater age of Mars’ potentially habitable early wet environments recorded in clay minerals identified from orbit.
