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Mindfully.org: "Small chunks are likely to survive next year's fall through the atmosphere; NASA officials hope those pieces will hit the ocean."
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A spacewalking astronaut did some massive housecleaning at the international space station Monday, tossing out a camera mounting and an ammonia tank weighing more than half a ton.
The outdated equipment was no longer needed and joined more than 9,000 pieces of orbital debris already being tracked from Earth.
"I'll be sending my bill in the mail for trash disposal," Clayton Anderson joked to Mission Control.
Anderson, a sportsman who enjoys officiating basketball games back on Earth, hurled the 1,400-pound, refrigerator-size ammonia tank away from the station with a single strong shove. His first toss was a 200-pound camera mounting.
Mission Control praised the tank throw as being "right down the middle."
"Well, in that case, give Brad Lidge and Roy Oswalt a call and tell them I just hummed a 17,500-mph fastball," Anderson said, referring to the star pitchers for his hometown Houston Astros.
For each celestial toss, Anderson leaned back on the end of the space station's 58-foot robot arm, as far from the space station as possible. He rocked forward and shouted "Jettison!" as he shoved the 4-foot camera mounting into space. He repeated the moves an hour later with the bulkier ammonia tank.
The tank had been launched in 2001 to provide spare coolant in case of a leak at the orbiting complex. The surplus ammonia was never needed, and the tank itself had exceeded its life expectancy.
NASA normally tries to avoid adding to the orbiting junkyard, but officials felt they had no choice in this case. The equipment had to be removed, and because of a looming 2010 deadline for ending all shuttle flights, NASA does not have room on its remaining missions to return the tank to Earth.
Flight controllers expect the ammonia tank to circle Earth for 10 or 11 months before re-entering the atmosphere and burning up.
There should be no danger of a collision between the free-floating tank and station before that happens, officials said. Small chunks are likely to survive next year's fall through the atmosphere; NASA officials hope those pieces will hit the ocean. The camera mounting should burn up entirely, much sooner than the tank, because of its smaller size.
Anderson threw the equipment in the opposite direction of the station's travel more than 200 miles up. The station was to be maneuvered later in the day into a higher orbit to provide additional clearance.
Russian cosmonaut Fyodor Yurchikhin joined Anderson outside the station, where he replaced a bad circuit breaker and cleaned a docking port.
The spacewalk lasted 7 1/2 hours, an hour longer than planned, allowing the two to complete some extra chores. Cosmonaut Oleg Kotov monitored the spacewalk from inside and operated the crane on which Anderson stood for the junk toss.
Anderson moved into the space station in June. The two cosmonauts have been on board since April.
"Our spaceship Earth is a beautiful place," Anderson marveled during the spacewalk, his first.
source: 23jul2007
Two International Space Station crew members Monday successfully wrapped up a 7-hour, 41-minute spacewalk that saw the removal and jettison of a refrigerator-size ammonia reservoir.
The spacewalk from the Quest Airlock ended at 2:06 p.m. EDT.
Astronaut Clay Anderson was the lead spacewalker, EV1, wearing the spacesuit with red stripes. Fyodor Yurchikhin, the cosmonaut and station commander, wearing the all-white suit, was EV2. Cosmonaut Oleg Kotov operated the Canadarm2 from the U.S. laboratory Destiny.
After leaving the airlock and setting up equipment, the first task was installation of a television camera stanchion. The spacewalkers took it from an external stowage platform and installed it on the Earth-facing side of the station's main truss at the interface Starboard 0-Port 1 (S0-P1) truss segments.
Next they moved to separate tasks. Anderson reconfigured a power supply for an S-Band Antenna Assembly, and then set up and got on a foot restraint at the end of Canadarm2. Yurchikhin replaced a circuit breaker, called a remote power controller module. It ensures power redundancy for a move of the Mobile Transporter rail car on the station's truss.
Back together, Anderson and Yurchikhin removed flight support equipment, where the camera stanchion had been mounted, and an attached Flight Releasable Attachment Mechanism. Together they have a mass of about 212 pounds.
While Anderson jettisoned them from the end of the arm, Yurchikhin moved to the Z1 truss, where he disconnected and stowed cabling associated with the ammonia reservoir, called the Early Ammonia Servicer (EAS).
The EAS was installed on the P6 truss during STS-105 in August 2001, as an ammonia replenishment reservoir if a leak had occurred. It was never used, and was no longer needed after the permanent cooling system was activated last December. The EAS has to be removed before the P6 truss can be moved to the end of the station's main truss.
With Anderson still on the arm, both crew members moved to the P6 Truss and released its remaining connections to the station. Once it was free, Anderson held the EAS while the arm maneuvered him to the jettison point, below the right side of the ISS main truss.
The EAS weighs a little over 1,400 pounds on Earth. The jettison was much like that of the stanchion equipment. Anderson shoved the EAS opposite the station's direction of travel.
A subsequent reboost by Russian thrusters changes the station's orbit to provide clearance from the EAS. The reboost also prepares for the Aug. 2 launch of the Progress 26 cargo carrier and the Aug. 7 launch of Discovery to the station.
The final scheduled spacewalk task was cleaning the Earth-facing docking port, or Common Berthing Mechanism (CBM) of the Unity node. That was done to prepare for the relocation of Pressurized Mating Adapter-3 (PMA-3), scheduled for late August.
The move is being made to clear the PMA-3's present position, on the starboard CBM of Unity, for a series of events that will culminate with the arrival of the Harmony node and its preparation to receive future space shuttles.
Crew members completed three get-ahead tasks. They removed an auxiliary equipment bag from the P6 Truss and attached it to the Z1 Truss. They also removed a malfunctioning Global Positioning System antenna on the S0 Truss and released bolts on two fluid trays attached to the S0. The trays are to be installed on Node 2, the Harmony node, during STS-120 this fall.
After cleanup Anderson and Yurchikhin re-entered Quest and concluded the spacewalk. It was the first spacewalk for Anderson and the third for Yurchikhin.
source: 23jul2007
CAPE CANAVERAL, Fla. — A spacewalking astronaut tossed two large chunks of junk off the international space station Monday, hurling the old equipment into orbit.
Clayton Anderson, a sportsman who enjoys officiating basketball games back on Earth, heaved a 1,400-pound, refrigerator-size ammonia tank away from the station. His first toss was a 200-pound camera mounting.
Mission Control declared the tank throw great and "right down the middle."
"Well, in that case, give Brad Lidge and Roy Oswalt a call and tell them I just hummed a 17,500-mph fastball," Anderson said, referring to the star pitchers for his hometown Houston Astros.
Anderson said the tank looked "majestic" as it tumbled away, and the 4-foot camera mounting resembled "a huge star."
"I'll be sending my bill in the mail for trash disposal," he joked with Mission Control.
For each celestial toss, Anderson leaned back on the end of the space station's 58-foot robot arm, as far from the space station as possible.
He rocked forward and shouted "Jettison!" as he shoved the outdated camera mounting into space.
The bulkier ammonia tank was a bit trickier.
The ammonia tank had been launched in 2001 to provide spare coolant in case of a leak at the orbiting complex. The surplus ammonia was never needed, and the tank itself had exceeded its life expectancy.
NASA normally tries to avoid adding to the orbiting junkyard, but officials felt they had no choice in this case. The equipment had to be removed, and because of a looming 2010 deadline for ending all shuttle flights, NASA does not have room on its remaining missions to return the tank to Earth.
Flight controllers expect the ammonia tank to orbit for 10 or 11 months before re-entering the atmosphere and burning up.
There should be no danger of a collision between the free-floating tank and station before that happens, officials said. Small chunks are likely to survive next year's fall through the atmosphere; NASA officials hope those pieces will hit the ocean.
The camera mounting should burn up entirely, much sooner than the tank, because of its smaller size.
Anderson threw the equipment in the opposite direction of the station's travel more than 200 miles up. The station will be maneuvered later in the day into a higher orbit to provide additional clearance.
Russian cosmonaut Fyodor Yurchikhin joined Anderson outside the station, where he replaced a bad circuit breaker. Cosmonaut Oleg Kotov stayed inside to oversee the spacewalk and operated the crane on which Anderson stood for the junk toss.
Anderson moved into the space station in June. The two cosmonauts have been on board since April.
"Our spaceship Earth is a beautiful place," Anderson marveled during the spacewalk, his first.
source: 23jul2007
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