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Space station to receive physics instrument today BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: May 19, 2011 
KENNEDY SPACE CENTER, FL--The Endeavour astronauts are gearing up to install a $2 billion cosmic ray detector on the International Space Station, a powerful magnet surrounded by complex sensors that will study high-energy particles from the depths of space and time to look for clues about the formation and evolution of the universe.
After moving it to a point over the right side of the shuttle, pilot Gregory Johnson and Gregory "Taz" Chamitoff, operating the station's robot arm from a work station inside the lab's multi-window cupola module, then plan to move AMS into position for attachment on the upper right side of the station's power truss. A motorized claw will lock the detector in place and electrical cables for power and data will be mated by remote control. "Taz and I are going to be working together, getting it in place and then attaching it," Johnson said in a NASA interview. "It's on top of the truss, and a lot of the assembly of the space station was using cameras that are on the bottom portion of the truss. So when we get up to the top of the truss, there aren't a lot of good cameras up there, so it's a little bit challenging trying to get good views of where we're putting the thing. "The shuttle robotic arm is helping us out," he added. "It's going to reach out and look at a certain angle that helps us. It's kind of like a remote camera, if you will, that'll be helping us and that'll be a primary view for us as we attach it onto the space station. We're also going to move very slowly. And so once we get it into place, there's three V-guides with claws, and actually a big claw that grabs it in the middle, and we'll just basically stick it in place and then the claws will close around it and attach it onto the space station." Chamitoff described the installation procedure as "a tricky operation." "The tolerances are really tight," he said. "You don't have camera views that show you clearances between things that you would like to know for sure that you're not hitting. So it takes some training to make sure we know exactly what we're expecting and get it in there right. But if all goes well it should be no problem. "I have to say on the AMS, which is the very expensive payload, the one that's most important, the attachment mechanism we're putting it on doesn't have the same level of redundancy as some of the other attachment mechanisms. In other words, there's not two motors if one fails for attaching it, for example. I'll be breathing a little better after that's been completed and I know that it's attached successfully, just because we don't have the redundancy there if something does go wrong." Once attached, no other crew interaction is required and data collection will begin almost immediately. AMS is roughly cube shaped, measuring 15 feet wide, 11 feet tall and 10 feet deep, tipping the scales at 15,251 pounds. Using a powerful magnet to bend the trajectories of high-energy cosmic rays -- charged particles from supernovas, neutron stars, black holes and other cosmic enigmas -- scientists will look for evidence of antimatter and as-yet-undetected dark matter, believed to make up a quarter of the the universe. AMS may even find evidence of strange particles made up of quarks in different arrangements than those found on Earth. Or something completely unexpected. The AMS "really probes the foundations of modern physics," said Sam Ting, a Nobel Laureate who manages the multinational experiment. "But to my collaborators and I, the most exciting objective of AMS is to probe the unknown, to search for phenomena which exist in nature but yet we have not the tools or the imagination to find." Built at CERN, the European Organization for Nuclear Research, and managed by the U.S. Department of Energy, the $2 billion AMS is an international collaboration between 16 nations, 60 institutes and some 600 physicists. Ting, a soft-spoken Chinese-American physicist who shared the 1976 Nobel Prize in physics, is a tireless advocate. "The largest accelerator on Earth is 16 miles in circumference, the large Hadron Collider, LHC," he said. "In LHC there are four big experiments. Thousands and thousands of physicists work there trying to understand the beginning of the universe, what is the origin of mass, why different particles have different masses. "The cost of ISS is about 10 times more than the LHC. The LHC has four experiments. On the space station, to study particle physics, the origin of the universe, (we only have) AMS. And that's why we're very grateful to the United States House of Representatives and the Senate, which passed the resolution to support NASA to have an additional flight to put us in space." The Large Hadron Collider is capable of generating energies as high as 7 trillion electron volts. To put that in perspective, 1 trillion electron volts is roughly equivalent to the energy of a single flying mosquito. A 100-watt light bulb burning for one hour is roughly equivalent to 2.2 trillion electron volts. But in particle physics, that energy is concentrated in a single sub-atomic particle and particles from deep space can have energies as high as 100 million trillion electron volts. "This means that no matter how accelerators are here on Earth, you cannot compete with the cosmos," Ting said. One of the many mysteries AMS was designed to explore is what happened to the anti-matter that must have been created in the big bang. Scientists believe equal amounts of matter and anti-matter were produced, but a slight imbalance -- or some other factor -- resulted in a universe dominated by normal matter. Or at least a nearby universe made up of normal matter. "If the universe comes from a big bang, before the big bang it is vacuum," Ting told reporters recently. "Nothing exists in vacuum. So in the beginning, you have (negatively charged) electron, you must have a (positively charged) positron so the charge is balanced. So you have matter, you must have antimatter, otherwise we would not have come from the vacuum. "So now the universe is 14 billion years old, you have all of us, made out of matter. The question is, where is the universe made out of antimatter? With this experiment, the reason we designed it to such a large size with so many layers of repetitive position detectors is to search for the existence of antimatter to the age of the observable universe, anti-helium, anti-carbon. "We can distinguish this particle from billions of ordinary particles," he said. "If you think about it, this is not a trivial job. In the city of Houston during the rainy season, you have about 10 billion raindrops per second. If you want to find one that's a different color, it's somewhat difficult. This illustrates the precision this detector is going to achieve." Dark matter, the mysterious, as-yet-undetected material believed to provide the glue -- gravity -- needed to hold galaxies and clusters of galaxies together, is believed to make up a quarter of the universe compared to the 4 percent made up of the normal matter familiar to human senses. The rest is believed to be in the form of dark energy, a repulsive force that appears to be speeding up the expansion of the universe. While AMS cannot directly detect dark matter, it can detect the particles that would be produced in dark matter collisions. AMS also will be on the lookout for so-called "strangelets," sub-atomic particles made up of quarks in different combinations than particles found on Earth. There are six types of quarks -- known as up, down, top, bottom, charm and strange -- but protons and neutrons making up normal matter seen on Earth are made up of just two -- different combinations of up quarks and down quarks. "The smallest particle are called quarks," Ting said. "We know six quarks exist. But it's very, very strange. All the material on Earth is made up of just two, up and down. We know in the accelerator, six types exist, but on Earth you only see the first two. So the simple question you want to ask is, where's the material made out of three types of quarks? Up, down and strange? It's a very simple question, but a very, very important question." Whatever AMS discovers, scientists will have plenty of data to work with. Some 25,000 particle detections per second are expected when the instrument is up and running. "We're gathering data at seven gigabits per second," said Trent Martin, the AMS project manager at the Johnson Space Center in Houston. "We can't send that huge amount of data down through the space station data system, it's just too much. "So the onboard computers actually go through a process of condensing that data down to just the data that we're truly interested in, compressing it as much as possible. We send down data on average at about six megabits per second, constantly for the entire time that AMS is on. The computers can store up data and we can burst it down at a much higher rate." Asked to speculate on what AMS might discover, Ting declined, saying "Most physicists who predict the future normally end up regretting it." "My responsibility and the responsibility of my senior collaborators is to make sure the instrument is correct," he said. "Because the detector is so sensitive, everything we measure is something new. We want to make sure it's done correctly." After AMS is in place on the station's starboard-three (S3) truss segment, the astronauts will spend the rest of the day preparing for a spacewalk Friday by Chamitoff and Andrew Feustel, the first of four excursions planned for Endeavour's mission. Both astronauts plan to spend the night in the station's Quest airlock module at a reduced pressure of 10.2 pounds per square inch to help purge nitrogen from their bloodstreams and prevent the bends when working in NASA's low-pressure spacesuits. The primary goals of the first spacewalk are to retrieve a materials science space exposure experiment; to install a replacement; and to hook up ammonia line jumpers to set up a pipeline from an ammonia coolant tank near the center of the power truss to the outboard left-side solar array. During a second spacewalk, ammonia will be pumped into the array reservoir to replace coolant that has been lost due to a slow leak. The shuttle astronauts will go to bed at 2:26 p.m. Here is an updated timeline of the crew's planned activities for flight day four (in EDT and mission elapsed time; includes revision C of the NASA television schedule; best viewed with fixed-width font): DATE/EDT...DD...HH...MM...SS...EVENT 05/18 10:56 PM...02...14...00...00...STS crew wakeup 05/19 01:56 AM...02...17...00...00...Shuttle arm (SRMS) grapples AMS 02:01 AM...02...17...05...00...ISS crew wakeup 02:21 AM...02...17...25...00...SRMS unberths AMS 03:01 AM...02...18...05...00...Station arm (SSRMS) grapples AMS 03:26 AM...02...18...30...00...SRMS ungrapples AMS 03:31 AM...02...18...35...00...ISS daily planning conference 03:41 AM...02...18...45...00...SSRMS moves AMS to attach point 04:31 AM...02...19...35...00...AMS PGSC deactivation 04:41 AM...02...19...45...00...SSRMS installs AMS (stage one) 04:56 AM...02...20...00...00...SSRMS installs AMS (stage two) 05:16 AM...02...20...20...00...EVA-1: Equipment lock preps 05:26 AM...02...20...30...00...AMS umbilical mate 05:41 AM...02...20...45...00...SSRMS releases AMS 06:11 AM...02...21...15...00...PAO event 06:31 AM...02...21...35...00...Crew meals begin 08:01 AM...02...23...05...00...Quick-disconnect familiarization 08:31 AM...02...23...35...00...EVA-1: Tools configured 10:01 AM...03...01...05...00...PAO event 10:21 AM...03...01...25...00...EVA-1: Procedures review 12:30 PM...03...03...34...00...Mission status briefing on NTV 12:51 PM...03...03...55...00...EVA-1: Mask prebreathe/tool config 01:36 PM...03...04...40...00...EVA-1: Airlock depress to 10.2 psi 01:56 PM...03...05...00...00...Garan sleep begins 02:01 PM...03...05...05...00...Soyuz departure preps 02:26 PM...03...05...30...00...STS crew sleep begins 03:01 PM...03...06...05...00...ISS daily planning conference 04:00 PM...03...07...04...00...Mission Management Team briefing on NTV 05:00 PM...03...08...04...00...Daily highlights reel on NTV (repeated hourly) 05:31 PM...03...08...35...00...ISS crew sleep begins 07:45 PM...03...10...49...00...Flight director update on NTV 09:45 PM...03...12...49...00...Flight director update replay on NTV 10:26 PM...03...13...30...00...STS crew/Garan wakeup
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VIDEO:
WEDNESDAY NIGHT FLIGHT DIRECTOR UPDATE 