Atom Definition

Faraday's Constant

[/caption]The atom definition is: A unit of matter, the smallest unit of an element, having all the characteristics of that element and consisting of a dense, central, positively charged nucleus surrounded by a system of electrons. The entire structure has an approximate diameter of 10-8 centimeters and characteristically remains undivided in chemical reactions except for limited removal, transfer, or exchange of certain electrons. Essentially, it is the smallest possible part of an element that still remains the element.

Under normal circumstances an atom can be broken down into any smaller particles, but we humans, have devised ways to break the atom apart. That is the entire basis of the atom bomb, particle colliders, and quarks. It takes high speed, high energy smashing of particles to break an atom. A particle collider does that and helps us understand some of the theories in particle physics. The results of an atom bomb are widely known. Quarks are extremely small particles that do not exist alone. They must group to form the protons, electron, and neutrons normally found in a single atom of an element. They have only been found as a result of a particle collider and in theory.

An atom itself is made up of three tiny kinds of particles called subatomic particles: protons, neutrons, and electrons. The protons and the neutrons make up the center of the atom called the nucleus and the electrons fly around above the nucleus in a small cloud. The electrons carry a negative charge and the protons carry a positive charge. In a normal (neutral) atom the number of protons and the number of electrons are equal. Often, but not always, the number of neutrons is the same, too. The opposing forces(negative and positive) attract and repel each other in the right way so as to keep the atom together. The universe could be looked at as one large atom. Everything in space attracts and repels just right so as to keep the whole together.

One type of theoretical ion propulsion spacecraft would have to take advantage of this atomic attraction and repulsion to operate. It takes advantage of magnetism and electricity to push a ship through space. Electricity, generated by the ship’s solar panels, gives a positive electrical charge to atoms inside the chamber. They are pulled by magnetism towards the back of the ship and then pushed by magnetic repulsion out of the ship. This steady stream of atoms going out of the spacecraft gives it the thrust it needs to go forward through space. NASA has tested other types of ion propulsion and found them lacking.

Here is another atom definition. Here on Universe Today we have a great article about atoms. Astronomy Cast has a good question and answer episode about interstellar travel, including a NASA link about ion propulsion.

Source:
Wikipedia

Spitzer, the Wallpaper Factory, Does it Again

Infrared portrait of the Small Magellanic Cloud, made by NASA's Spitzer Space Telescope

At the end of the proverbial day, space-based missions like Spitzer produce millions of observations of astronomical objects, phenomena, and events. And those terabytes of data are used to test hypotheses in astrophysics which lead to a deeper understanding of the universe and our home in it, and perhaps some breakthrough whose here-on-the-ground implementation leads to a major, historic improvement in human welfare and planetary ecosystem health.

But such missions also leave more immediate legacies, in terms of the pleasure they bring millions of people, via the beauty of their images (not to mention posters, computer wallpaper and screen savers, and even inspiration for avatars).

Some recent results from one of Spitzer’s programs – SAGE-SMC – are no exception.

The image shows the main body of the Small Magellanic Cloud (SMC), which is comprised of the “bar” on the left and a “wing” extending to the right. The bar contains both old stars (in blue) and young stars lighting up their natal dust (green/red). The wing mainly contains young stars. In addition, the image contains a galactic globular cluster in the lower left (blue cluster of stars) and emission from dust in our own galaxy (green in the upper right and lower right corners).

The data in this image are being used by astronomers to study the lifecycle of dust in the entire galaxy: from the formation in stellar atmospheres, to the reservoir containing the present day interstellar medium, and the dust consumed in forming new stars. The dust being formed in old, evolved stars (blue stars with a red tinge) is measured using mid-infrared wavelengths. The present day interstellar dust is weighed by measuring the intensity and color of emission at longer infrared wavelengths. The rate at which the raw material is being consumed is determined by studying ionized gas regions and the younger stars (yellow/red extended regions). The SMC is one of very few galaxies where this type of study is possible, and the research could not be done without Spitzer.

This image was captured by Spitzer’s infrared array camera and multiband imaging photometer (blue is 3.6-micron light; green is 8.0 microns; and red is combination of 24-, 70- and 160-micron light). The blue color mainly traces old stars. The green color traces emission from organic dust grains (mainly polycyclic aromatic hydrocarbons). The red traces emission from larger, cooler dust grains.

The image was taken as part of the Spitzer Legacy program known as SAGE-SMC: Surveying the Agents of Galaxy Evolution in the Tidally-Stripped, Low Metallicity Small Magellanic Cloud.

The Small Magellanic Cloud (SMC), and its larger sister galaxy, the Large Magellanic Cloud (LMC), are named after the seafaring explorer Ferdinand Magellan, who documented them while circling the globe nearly 500 years ago. From Earth’s southern hemisphere, they can appear as wispy clouds. The SMC is the further of the pair, at 200,000 light-years away.

Recent research has shown that the galaxies may not, as previously suspected, orbit around our galaxy, the Milky Way. Instead, they are thought to be merely sailing by, destined to go their own way. Astronomers say the two galaxies, which are both less evolved than a galaxy like ours, were triggered to create bursts of new stars by gravitational interactions with the Milky Way and with each other. In fact, the LMC may eventually consume its smaller companion.

Karl Gordon, the principal investigator of the latest Spitzer observations at the Space Telescope Science Institute in Baltimore, Maryland, and his team are interested in the SMC not only because it is so close and compact, but also because it is very similar to young galaxies thought to populate the universe billions of years ago. The SMC has only one-fifth the amount of heavier elements, such as carbon, contained in the Milky Way, which means that its stars haven’t been around long enough to pump large amounts of these elements back into their environment. Such elements were necessary for life to form in our solar system.

Studies of the SMC therefore offer a glimpse into the different types of environments in which stars form.

“It’s quite the treasure trove,” said Gordon, “because this galaxy is so close and relatively large, we can study all the various stages and facets of how stars form in one environment.” He continued: “With Spitzer, we are pinpointing how to best calculate the numbers of new stars that are forming right now. Observations in the infrared give us a view into the birthplace of stars, unveiling the dust-enshrouded locations where stars have just formed.”

Little Galaxy with a Tail (Small Magellanic Cloud imaged by Spitzer)

This image shows the main body of the SMC, which is comprised of the “bar” and “wing” on the left and the “tail” extending to the right. The tail contains only gas, dust and newly formed stars. Spitzer data has confirmed that the tail region was recently torn off the main body of the galaxy. Two of the tail clusters, which are still embedded in their birth clouds, can be seen as red dots.

Source: Spitzer

Merging White Dwarfs Set Off Supernovae

Composite image of M31. Inset shows central region as seen by Chandra. Credit: NASA/CXC/MPA/ M.Gilfanov & A.Bogdan;

New results from the Chandra X-Ray Observatory suggests that the majority of Type Ia supernovae occur due to the merger of two white dwarfs. This new finding provides a major advance in understanding the type of supernovae that astronomers use to measure the expansion of the Universe, which in turns allows astronomers to study dark energy which is believed to pervade the universe. “It was a major embarrassment that we still didn’t know the conditions and progenitor systems of some the most spectacular explosions in the universe,” said Marat Gilfanov of the Max Planck Institute for Astrophysics, at a press conference with reporters today. Gilfanov is the lead author of the study that appears in the Feb. 18 edition of the journal Nature.

Type Ia supernovae serve as cosmic mile markers to measure expansion of the universe. Because they can be seen at large distances, and they follow a reliable pattern of brightness. However, until now, scientists have been unsure what actually causes the explosions.

Most scientists agree a Type Ia supernova occurs when a white dwarf star — a collapsed remnant of an elderly star — exceeds its weight limit, becomes unstable and explodes. The two leading candidates for what pushes the white dwarf over the edge are the merging of two white dwarfs, or accretion, a process in which the white dwarf pulls material from a sun-like companion star until it exceeds its weight limit.

“Our results suggest the supernovae in the galaxies we studied almost all come from two white dwarfs merging,” said co-author Akos Bogdan, also of Max Planck. “This is probably not what many astronomers would expect.”

The difference between these two scenarios may have implications for how these supernovae can be used as “standard candles” — objects of a known brightness — to track vast cosmic distances. Because white dwarfs can come in a range of masses, the merger of two could result in explosions that vary somewhat in brightness.

Because these two scenarios would generate different amounts of X-ray emission, Gilfanov and Bogdan used Chandra to observe five nearby elliptical galaxies and the central region of the Andromeda galaxy. A Type Ia supernova caused by accreting material produces significant X-ray emission prior to the explosion. A supernova from a merger of two white dwarfs, on the other hand, would create significantly less X-ray emission than the accretion scenario.

The scientists found the observed X-ray emission was a factor of 30 to 50 times smaller than expected from the accretion scenario, effectively ruling it out.

So, for example, the Chandra image above would be about 40 times brighter than observed if Type Ia supernova in the bulge of this galaxy were triggered by material from a normal star falling onto a white dwarf star. Similar results for five elliptical galaxies were found.

This implies that white dwarf mergers dominate in these galaxies.

An open question remains whether these white dwarf mergers are the primary catalyst for Type Ia supernovae in spiral galaxies. Further studies are required to know if supernovae in spiral galaxies are caused by mergers or a mixture of the two processes. Another intriguing consequence of this result is that a pair of white dwarfs is relatively hard to spot, even with the best telescopes.

“To many astrophysicists, the merger scenario seemed to be less likely because too few double-white-dwarf systems appeared to exist,” said Gilfanov. “Now this path to supernovae will have to be investigated in more detail.”

Source: NASA

Astronomical Eye Candy from WISE First Images

The immense Andromeda galaxy, also known as Messier 31 or simply M31, is captured in full in this February 2010 image from WISE. credit: NASA/JPL-Caltech/UCLA

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The WISE (Wide-field Infrared Survey Explorer) mission isn’t wasting any time in making observations and releasing images. Already the new infrared observatory has spied its first comet and first near Earth asteroid, and today released a “sweet” collection of eye candy from across the universe. “We’ve got a candy store of images coming down from space,” said Edward (Ned) Wright of UCLA, the principal investigator for WISE. “Everyone has their favorite flavors, and we’ve got them all.”

Four new, processed pictures illustrate a sampling of the mission’s targets — a bursting star-forming cloud, a faraway cluster of hundreds of galaxies, a wispy comet, and above, the grand Andromeda galaxy as we’ve never seen it before, with new details of its ringed arms of stars .

NGC 3603, as seen by WISE. credit: NASA/JPL-Caltech/UCLA

Another image shows a bright and choppy star-forming region called NGC 3603, lying 20,000 light-years away in the Carina spiral arm of our Milky Way galaxy. This star-forming factory is churning out batches of new stars, some of which are monstrously massive and hotter than the sun. The hot stars warm the surrounding dust clouds, causing them to glow at infrared wavelengths.

Siding Spring Comet via WISE. credit: NASA/JPL-Caltech/UCLA

This image shows the beauty of a comet called Siding Spring. As the comet parades toward the sun, it sheds dust that glows in infrared light visible to WISE. The comet’s tail, which stretches about 10 million miles, looks like a streak of red paint. A bright star appears below it in blue. WISE is expected to find perhaps dozens of comets, and bagged its first one on January 22, 2010. WISE will help unravel clues locked inside comets about how our solar system came to be.

WISE's view of the Fornax Cluster. credit: NASA/JPL-Caltech/UCLA

The fourth WISE picture is of the Fornax cluster, a region of hundreds of galaxies all bound together into one family. These galaxies are 60 million light-years from Earth. The mission’s infrared views reveal both stagnant and active galaxies, providing a census of data on an entire galactic community.

“All these pictures tell a story about our dusty origins and destiny,” said Peter Eisenhardt, the WISE project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “WISE sees dusty comets and rocky asteroids tracing the formation and evolution of our solar system. We can map thousands of forming and dying solar systems across our entire galaxy. We can see patterns of star formation across other galaxies, and waves of star-bursting galaxies in clusters millions of light years away.”

Since WISE began its scan of the entire sky in infrared light on Jan. 14, the space telescope has beamed back more than a quarter of a million raw, infrared images. The mission will scan the sky one-and-a-half times by October. At that point, the frozen coolant needed to chill its instruments will be depleted. However, the team predicts the spacecraft will be still be operational for 3 additional months following the 10 month prime mission.

So, stay tuned for more images from WISE!

Source: NASA

Universe Puzzle

Small Magellanic Cloud. Image credit: NASA/ESA/HST

I’m trying something new, here in Universe Today, a puzzle.

This is, I hope, a puzzle that cannot be answered by five minutes spent googling, a puzzle that requires you to cudgel your brains a bit, and do some lateral thinking.

There are no prizes for the first correct answer – the judge’s decision (mine!) will be final – but I do hope that you’ll have lots of fun.

What do David, Nicholas, and Ferdinand have in common?

Post your guesses in the comments section, and check back later at this same post to find the answer. To make this puzzle fun for everyone, please don’t include links or extensive explanations with your answer, until after the answer has been given. Good luck!

Answer has now been posted below:

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Malin1 (Hubble Space Telescope image courtesy of Aaron Barth)

Mayall's Object (Hubble Space Telescope)

David Malin (Malin I), Nicholas Mayall (Mayall’s object, or Arp 148), and Ferdinand Magellan (the Magellanic Clouds) all have galaxies named after them!

I should have said that David, Nicholas, and Ferdinand have a deep association with the topics we regularly cover here in Universe Today – astronomy, space, telescopes, etc.

Congratulations to IVAN3MAN, who guessed correctly first, and to all those who came up with equally good answers – all must have prizes.

Stay tuned for another Universe Puzzle, next week (HINT: I will pose a quite different kind of puzzle then).

Missing Early Stars Found, With No Place Left to Hide

The Fornax dwarf galaxy is one of our Milky Way’s neighbouring dwarf galaxies and a good example of what an early dwarf galaxy might have been like. This image was composed from data from the Digitized Sky Survey 2. Credit: ESO
The Fornax dwarf galaxy is one of our Milky Way’s neighbouring dwarf galaxies and a good example of what an early dwarf galaxy might have been like. This image was composed from data from the Digitized Sky Survey 2. Credit: ESO

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Astronomer sleuths have solved a cosmic mystery by finding primitive stars that have been stealthily concealed. Using ESO’s Very Large Telescope a group of astronomers have uncovered an important astrophysical puzzle concerning the oldest stars in our galactic neighborhood — which is crucial for our understanding of the earliest stars in the Universe. . “We have, in effect, found a flaw in the forensic methods used until now,” said Else Starkenburg, lead author of a paper reporting the new findings. “Our improved approach allows us to uncover the primitive stars hidden among all the other, more common stars.”

Primitive stars are thought to have formed from material forged shortly after the Big Bang, 13.7 billion years ago. They typically have less than one thousandth the amount of chemical elements heavier than hydrogen and helium found in the Sun and are called “extremely metal-poor stars.” They belong to one of the first generations of stars in the nearby Universe. Such stars are extremely rare and mainly observed in the Milky Way.

The Sculptor dwarf galaxy is one of our Milky Way’s neighbouring dwarf galaxies. Credit: ESO/Digitized Sky Survey 2

Cosmologists think that larger galaxies like the Milky Way formed from the merger of smaller galaxies. Our Milky Way’s population of extremely metal-poor or “primitive” stars should already have been present in the dwarf galaxies from which it formed, and similar populations should be present in other dwarf galaxies. “So far, evidence for them has been scarce,” said co-author Giuseppina Battaglia. “Large surveys conducted in the last few years kept showing that the most ancient populations of stars in the Milky Way and dwarf galaxies did not match, which was not at all expected from cosmological models.”

Element abundances are measured from spectra, which provide the chemical fingerprints of stars. The Dwarf galaxies Abundances and Radial-velocities Team used the FLAMES instrument on ESO’s Very Large Telescope to measure the spectra of over 2000 individual giant stars in four of our galactic neighbors, the Fornax, Sculptor, Sextans and Carina dwarf galaxies. Since the dwarf galaxies are typically 300,000 light years away — which is about three times the size of our Milky Way — only strong features in the spectrum could be measured, like a vague, smeared fingerprint. The team found that none of their large collection of spectral fingerprints actually seemed to belong to the class of stars they were after, the rare, extremely metal-poor stars found in the Milky Way.

The team of astronomers around Starkenburg has now shed new light on the problem through careful comparison of spectra to computer-based models. They found that only subtle differences distinguish the chemical fingerprint of a normal metal-poor star from that of an extremely metal-poor star, explaining why previous methods did not succeed in making the identification.

The astronomers also confirmed the almost pristine status of several extremely metal-poor stars thanks to much more detailed spectra obtained with the UVES instrument on ESO’s Very Large Telescope. “Compared to the vague fingerprints we had before, this would be as if we looked at the fingerprint through a microscope,” explains team member Vanessa Hill. “Unfortunately, just a small number of stars can be observed this way because it is very time consuming.”

“Among the new extremely metal-poor stars discovered in these dwarf galaxies, three have a relative amount of heavy chemical elements between only 1/3000 and 1/10 000 of what is observed in our Sun, including the current record holder of the most primitive star found outside the Milky Way,” said team member Martin Tafelmeyer.

“Not only has our work revealed some of the very interesting, first stars in these galaxies, but it also provides a new, powerful technique to uncover more such stars,” concluded Starkenburg. “From now on there is no place left to hide!”

Source: ESO

Astronauts Open New Window on the Universe

"Let there be light! Cupola windows open toward Sahara desert. Priceless!\" Tweeted ISS astronaut Soichi Noguchi.

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“Let there be light! Cupola windows open toward Sahara desert. Priceless!” Tweeted ISS astronaut Soichi Noguchi from the ISS.

It’s the moment we’ve all been waiting for: the opening on the windows of the new Cupola on the International Space Station. And it was incredible.

“As expected, the view through window seven is absolutely spectacular,” ISS commander Jeff Williams said. “When we have the others around it open, it will give us a view of the entire globe. Absolutely incredible.”

Shutters are opened on the new Cupola on the ISS. Credit: NASA TV

The new $27 million bay window was uncovered during the third EVA of the STS-130 mission by spacewalkers Nick Patrick and Bob Behnken, who removed the protective launch covers and bolts. Then, from the inside, each of the seven shutters was cranked opened and closed one at a time, to test the view — and the shutters. In case there were any problems, the astronauts out on EVA could help close the shutters.

Later, all the shutters were opened at once for the full view. “I don’t think space station’s ever going to be the same after this,” Mission Control radioed to the ISS.

The new observation deck will allow astronauts unprecedented 360-degree views of Earth and space, while providing a new location for robotic operations where astronauts inside the ISS can actually watch directly what they doing with the CanadArm2 on the ISS, instead of completely relying on computer inputs and camera views. The Cupola is attached to the nadir, or Earth–facing port of the new Tranquility node, a $380 million addition to the station that was delivered to the ISS on the current space shuttle mission.

Built by the Italian space agency, the Cupola is 1.5 meters (5 feet) tall and about 3 meters (10 feet) in diameter. Six rectangular windows encircle the dome, with a large circular window in the middle.

Mission managers said at a press conference last week that the windows will remain shuttered most of the time to protect the 4-pane fused silica glass from micrometeroid strikes. The large central window shutter may be allowed to opened more frequently since it is facing towards Earth and away from potential incoming space debris.

Nancy peeks through a model of the Cupola that was at Kennedy Space Center. Image by Robin Hobson.

A model of the Cupola was set up at the press room at Kennedy Space Center. I asked about the windows and the potential of problems if they are hit by micrometeroids, and was told that if the windows are dinged or significantly damaged, they can be repaired or replaced on orbit. There are spare window assemblies built, but they aren’t currently on the ISS nor are there plans to bring them up, for now. For minor damage, the shutters would be closed until the repairs could be done. For major damage, the Cupola has a hatch, so there is the potential to close off Cupola, but mission managers said that option has a very low likelihood of occurring.

Asteroid Might be Visible to Naked Eye on Feb. 17

Asteroid Vesta as seen by NASA's Hubble Space Telescope. Image credit: NASA/ESA/U of Md./STSci/Cornell/SWRI/UCLA

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An asteroid could be visible with binoculars, or even the naked eye on Wednesday, February 17, 2010. No, it’s not coming close to Earth, although this second most massive object in the asteroid belt will be at its closest point to Earth in its orbit, about 211,980,000 kilometers (131,700,000 miles) away. Asteroid Vesta – one of the asteroids that the Dawn spacecraft will visit – will be at opposition on Wednesday, meaning it is opposite the sun as seen from Earth, and is closest to us. Vesta is expected to shine at magnitude 6.1, and that brightness should make it visible for those with clear skies and a telescope, but perhaps even those blessed with excellent vision and little or no light pollution. Vesta will be visible in the eastern sky in the constellation Leo, and will continue to be visible — although less so — in the coming months.

What makes this space rock so prominent these days? Along with its relative proximity at this point, a full half of the asteroid is being bathed by sunlight when seen from Earth, making it appear brighter. Another attribute working in the observer’s favor is that Vesta has a unique surface material that is not as dark as most main belt asteroids – allowing more of the sun’s rays to reflect off its surface.

For more info about observing Vesta, check out this article from Sky & Telescope.

If you get lucky enough to see Vesta, and want to learn more about it, check out this info on the Dawn mission website. Dawn is currently motoring its way through the asteroid belt, will begin its exploration of Vesta in the summer of 2011.

Source: JPL

Scenes from Space: Best Images from STS-130 (so far…)

Astronaut Robert Behnken during the first EVA of the mission. Credit: NASA

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The STS-130 mission has provided some of the most amazing photos of any space shuttle mission to date — from a stunning shot of space shuttle Endeavour silhouetted against Earth’s colorful atmosphere, to incredible views of the International Space station, to the always amazing photos of astronauts at work in space. But that’s only the beginning! Take a look at a sampling of some of the best images from the mission so far. Above, astronaut Bob Behnken works outside the ISS during the first EVA of the mission.

Close-up view of Endeavour's nose section as seen from the ISS. Credit: NASA

During my time in at Kennedy Space Center the past couple of weeks, I had the chance to see space shuttle Endeavour up close. But not quite this close! Here’s the view the ISS astronauts had as the space shuttle pulled up for docking to the space station.

great view of the Tranquility module before being attached to the ISS. Credit: NASA

This is an amazing view of our home in space, the ISS, and a great way to see the international partnership of nations at work: CanadArm 2 from Canada hangs onto the Tranquility Node built by Europe; also a view of Japan’s JEM module, and the Russian Soyuz and a US space shuttle that are docked to the ISS.

Robert Behnken hangs on. Credit: NASA

I get vertigo just looking at this one! Hang on Bob Behnken!! But what a view. During the first EVA of the mission, Behnken and fellow spacewalker Nicholas Patrick relocated a temporary platform from the Special Purpose Dexterous Manipulator, or Dextre, to the station’s truss structure and installed two handles on the robot. Once Tranquility was structurally mated to Unity, the spacewalkers connected heater and data cables that integrated the new module with the rest of the station’s systems. They also pre-positioned insulation blankets and ammonia hoses that the same two spacewalkers connected up Tranquility to the station’s cooling radiators during the mission’s second spacewalk.

Superman, a.k.a Terry Virts zooms through the Zarya module. Credit: NASA

This is what we all want to do in space. Pilot Terry Virts does Superman in fine style in the Zarya Functional Cargo Block (FGB).

Fresh fruit and veggies are a rare treat in space. Credit: NASA

Fresh food in space is one thing we haven’t figured out how to do yet, so any arriving spacecraft must be extremely welcome for the crunchy and succulent apples, oranges, carrots, etc. they bring. It’s interesting to see NASA uses the same green bags that I use at home to keep fruit and vegetables fresh longer. That’s ISS Commander Jeff Williams with the goodies.

Endeavour silhouetted against Earth's atmospere. Credit: NASA

I know we published this image earlier, but it is so amazing, I had to include it in this gallery. Just absolutely stunning.

Another great shot of astronaut Bob Behnken during EVA-1. Credit: NASA

A great shot of astronaut Bob Behnken during EVA-2, a five-hour, 54-minute spacewalk. Behnken and Nicholas Patrick connected two ammonia coolant loops, installed thermal covers around the ammonia hoses, outfitted the Earth-facing port on the Tranquility node for the relocation of its Cupola, and installed handrails and a vent valve on the new module.

Moving the cupola. Credit: NASA

Another great view of the action taking place at the ISS this week. In the grasp of the Canadarm2, the cupola was relocated from the forward port to the Earth-facing port of the International Space Station’s newly installed Tranquility node. The cupola is a robotic control station with six windows around its sides and another in the center that will provide a panoramic view of Earth, celestial objects and visiting spacecrafts. With the installation of Tranquility and cupola, the space station is about 90 percent complete.

Night launch of Endeavour. Credit: NASA

Having witnessed the launch personally, I have to include a couple of incredible pictures of the night launch of Endeavour. Speaking of launches, the latest word is that the next mission may be an early morning launch, as STS-131 has slipped to launching no earlier than April 5, 2010 at 6:27 am EDT. We’ll keep you posted.

Launch, another view. Credit: NASA

For more images, see the STS-130 gallery on NASA’s website.

Dark Matter Detector Heading to the ISS This Summer

AMS-2 during integration activities at CERN facility in Switzerland. Credit: ESA

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The long-awaited experiment that will search for dark matter is getting closer to heading to the International Space Station. The Alpha Magnetic Spectrometer (AMS) is undergoing final testing at ESA’s Test Centre in the Netherlands before being launched on the space shuttle to the ISS, currently scheduled for July, 2010. The AMS will help scientists better understand the fundamental issues on the origin and structure of the Universe by observing dark matter, missing matter and antimatter. As a byproduct, AMS will gather other information from cosmic radiation sources such as stars and galaxies millions of light years from our home galaxy.

ISS officials have been touting that science is now beginning to be done in earnest on the orbiting laboratory. The AMS will be a giant leap in science capability for the ISS. Not only is it the biggest scientific instrument to be installed on the International Space Station (ISS), but also it is the first magnetic spectrometer to be flown in space, and the largest cryogenically cooled superconducting magnet ever used in space. It will be installed on the central truss of the ISS.
Location of where the AMS will be located on the exterior of the ISS. Credits: CERN et Universite de Geneve
AMS had been cut from the ISS program following the 2003 Columbia shuttle accident, but the outcry over the cancellation forced NASA to rethink their decision. Most of AMS’s $1.5-billion costs have been picked up the international partners that NASA wishes to stay on good terms with. 56 institutes from 16 countries have contributed to the AMS project, with Nobel laureate Samuel Ting coordinating the effort.

In an interview with the BBC, Ting said results from AMS may take up to three years to search for antimatter in other galaxies, and dark matter in our own.
The instrument was built at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. The first part of the tests was also conducted at CERN, when the detector was put through its paces using a proton beam from CERN’s Super Proton Synchrotron accelerator to check its momentum resolution and its ability to measure particle curvature and momentum.

AMS’s ability to distinguish electrons from protons was also tested. This is very important for the measurement of cosmic rays, 90% of which are protons and constitute a natural background for other signals that interest scientists. AMS will be looking for an abundance of positrons and electrons from space, one of the possible markers for dark matter.

Once the extensive testing is complete, AMS will leave ESTEC at the end of May on a special US Air Force flight to Kennedy Space Center in Florida. It will be launched to the ISS on the Space Shuttle Endeavour on flight STS-134, now scheduled for July.

Source: ESA