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Science/Astronomy

Spacewalkers continue repair of cosmic ray detector

Italian astronaut Luca Parmitano and NASA crewmate Drew Morgan stepped outside the International Space Station Friday for the second of four spacewalks to repair a $2 billion cosmic ray detector.

Floating in the Quest airlock compartment, the astronauts switched their spacesuits to battery power at 7:02 a.m. EST, officially kicking off the year’s tenth spacewalk, the 223rd since station assembly began in 1998. A few moments later, they made their way outside to continue work to upgrade the Alpha Magnetic Spectrometer’s coolant system.

For identification once the spacewalk begins, Parmitano, call sign EV-1, is wearing a suit with red stripes and is using helmet camera 11 while Morgan, EV-2, is wearing an unmarked suit with helmetcam 18.

The 7.5-ton AMS, mounted on the right side of the station’s power truss, was not designed to be serviced by spacewalking astronauts, and fixing its failing cooling system is considered the most challenging repair work since shuttle astronauts serviced the Hubble Space Telescope.

During an initial outing last Friday, Parmitano and Morgan removed a debris shield from the AMS, installed handrails, cut zip ties holding cables and coolant lines in place and pulled back insulation, getting well ahead of schedule and carrying out several tasks originally planned for the second excursion.

Today’s revised spacewalk is focused on prepping power and data cables needed by a new coolant pump module; installing a mounting bracket to hold the new pump package in place; cutting a 6-millimeter-wide line to vent carbon dioxide coolant overboard; and cutting eight more even smaller lines that carry CO2 through the instrument.

During a third spacewalk Dec. 2, the astronauts will attach the new pump module and splice, or swage, new coolant lines to the ones that were cut earlier. A fourth spacewalk is planned to close out the overhaul and address any follow-up work that might be needed after a series of tests.

The Alpha Magnetic Spectrometer was designed to detect high-energy cosmic rays in long-term research to learn what happened to the antimatter presumably cooked up in the big bang. It also is looking for clues about the nature of unseen dark matter and the equally mysterious dark energy that is speeding up the expansion of the universe.

Launched to the station in 2011 aboard the next-to-last space shuttle mission, the AMS was designed to operate for three years. But the instrument managed an additional five years before being hobbled by coolant pump failures, and NASA opted to attempt the spacewalk repair job to extend its life.

“It’s not only replacing the pumps, it’s replacing the accumulator, its replacing the heat exchangers, heaters, valves, that whole pump package,” said Ken Bollweg, the AMS project manager at the Johnson Space Center in Houston. “It’s a whole new package that’s designed to extend the life until the end of space station.”

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Science/Astronomy

Astronauts complete bonus objectives in first in series of AMS repair spacewalks

Two astronauts ventured outside the International Space Station Friday for the first of four spacewalks to repair a $2 billion cosmic ray detector, breezing through work to prep the device for invasive surgery to splice in new coolant pumps and extend the instrument’s life probing the composition of the universe.

“We’re going to perform what could be considered open heart surgery on this amazing experiment,” said Italian astronaut Luca Parmitano, the current space station commander.

The 7.5-ton patient in this case is the Alpha Magnetic Spectrometer, or AMS, the most expensive science instrument aboard the space station and one that was not designed to be serviced in orbit. As such, the “operation” is considered one of the most challenging since work to repair and upgrade the Hubble Space Telescope.

“It’s definitely towards the top of the list, if not on the top,” said Tara Jochim, the AMS repair manager at the Johnson Space Center in Houston.

Floating in the station’s Quest airlock, Parmitano and NASA astronaut Drew Morgan switched their spacesuits to battery power at 6:39 a.m. EST to officially kick off the year’s ninth spacewalk.

The last time Parmitano walked in space in July 2013 his suit malfunctioned, flooding his helmet with water and forcing an emergency return to the station’s airlock. NASA developed procedures to prevent a recurrence and no similar problems have occurred since then.

The major objectives of Friday’s spacewalk were to prep the AMS for its planned surgery, setting out tools and equipment before removing a protective debris shield, giving them access to the instrument’s thermal control system.

After carefully tossing the debris shield overboard, the spacewalkers attached two handrails to help them move about the device and, reaching into the AMS, snipped a half dozen zip ties and cut a cord to fold back insulation blankets.

The work went much faster than expected and the astronauts were able to work through several items originally planned for their second spacewalk next Friday. That’s when the actual repair work will begin. The third and fourth spacewalks will be officially scheduled after managers assess the results of the first two outings.

Parmitano and Morgan returned to the airlock, closed the hatch and began repressurizing at 1:18 p.m. to wrap up a six-hour 39-minute spacewalk, the 222nd since the station assembly began in 1998, the ninth so far this year, the third for Parmitano and the fourth for Morgan.

“I’ve got to tell you, you made the ground team awfully happy and proud of you guys today, just some excellent, excellent work,” Canadian astronaut Jeremy Hansen radioed from mission control. “We are very, very pleased with where we stand moving forward, getting the Alpha Magnetic Spectrometer back up and running. So congratulations to all of you.”

Unlike the Hubble Space Telescope, designed from scratch to be serviced by spacewalking astronauts, the Alpha Magnetic Spectrometer was never intended to be worked on in space. As such, it was not equipped with the sorts of fasteners, cables, handrails and internal clearances needed by astronauts working in bulky, pressurized suits.

In the end, it took engineers and astronauts four years to come up with a workable plan, developing some two-dozen custom tools and testing procedures during multiple underwater training runs. Parmitano and Morgan completed seven full-duration training exercises before launching to the station in July.

“We had to go off and figure out how to create a work site, we had to build new handrails to install on existing hardware, we had to deal with existing sharp edges and in a lot of cases, we’re creating new sharp edges using tools that have sharp edges on them,” said Jochim.

“We did as much as we could to minimize that risk to the crew member and then, of course, to the (repair) of the payload itself,” she said. “But they are certainly very challenging and technically difficult EVAs.”

Launched in 2011 on the next-to-last space shuttle mission, the Alpha Magnetic Spectrometer, is one of the most expensive science instruments ever launched.

It is built around a powerful electromagnet that bends the trajectories of electrically charged cosmic ray particles created in supernova explosions and other extreme-energy events, allowing researchers studying the trajectories to characterize their velocities and energies.

The goal is to learn what happened to the antimatter thought to have been created in the big bang birth of the cosmos, to learn more about the unseen dark matter that permeates space and, possibly, gain insights into the nature of dark energy, the mysterious repulsive force that is speeding up the expansion of the universe.

Designed to operate for just three years, the AMS proved longer lived than expected, detecting more than 145 billion cosmic rays during eight-and-a-half years of operation. But the instrument has been hobbled in recent months by the staggered failures of four small pumps needed to circulate carbon dioxide coolant through its sensitive detectors.

To repair the AMS, Parmitano and Morgan will have to cut through eight small coolant lines during their second spacewalk and splice in, or “swage,” new lines leading to a custom-built replacement pump module launched to the station earlier this month. The pump module will be installed during the third spacewalk.

“We’re going to cut tubes, and then fuse them with other tubes (launched) from Earth and install a completely new pump to help the refrigeration work, keeping the magnet cold so the the Alpha Magnetic Spectrometer can work,” Parmitano said. “This is really the first time any of these actions have been attempted.”

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Science/Astronomy

Senators Propose Extending Space Station’s Life to 2030 in NASA Authorization Bill

The International Space Station may get a new lease on life.

The orbiting complex is currently expected to end operations in 2024, but a group from the U.S. Senate’s Commerce, Science, and Transportation Committee proposes continuing the program until 2030 — a full six years later — in a new NASA 2019 authorization act.

“By extending the ISS through 2030, this legislation will help grow our already burgeoning space economy, fortifying the United States’ leadership in space, increasing American competitiveness around the world, and creating more jobs and opportunity here at home,” said U.S. Sen. Ted Cruz, R-Texas, chair of the Subcommittee on Aviation and Space, in the joint statement.

One probable motivation for this extension would be the space station’s growing in-space manufacturing capability, given some of the language in the authorization act. “The [NASA] administrator shall establish a low-Earth orbit commercialization program to encourage the fullest commercial use and development of space by private entities in the United States,” it states in one of its sections. The act further asks NASA to “maintain a national microgravity laboratory in space” even after the space station is decommissioned.

The other senatorial signatories include subcommittee ranking member Kyrsten Sinema, D-Ariz.; Roger Wicker, R-Miss.; and Maria Cantwell, D-Wash., chair and ranking member of the larger science committee. SpaceNews points out that the 2030 extension proposal was also included in last year’s Space Frontier Act, which the Senate passed unanimously but which the House did not pass.

Since the ISS is an international project, its extension will likely depend on the commitment of the other partners in the laboratory. The Russian Federal Space Agency (Roscosmos), the European Space Agency and the Japan Aerospace Exploration Agency are the partners that currently provide the most funding. Each agency must also determine budget priorities in the wake of NASA’s push to land humans on the moon in 2024, a program for which it is also seeking international participation.

The senators also want NASA to have the Exploration Upper Stage of the Space Launch System rocket ready for the 2024 moon landing. The powerful upper stage can carry more equipment to the lunar surface to support ongoing astronaut operations.

The authorization act asks for “scheduled availability sufficient for use on the third launch of the Space Launch System,” which (while not stated explicitly in the text) is set for 2024 and would be the scheduled first moon landing by humans since 1972. NASA, in a recent statement about Boeing production of the Space Launch System, said it expected to have the stage ready for the fourth SLS mission in 2025.

The act also directs NASA to continue developing the Wide Field Infrared Survey Telescope (WFIRST). NASA requested that this project be canceled in its fiscal year 2020 budget request in order to support budget overruns on the James Webb Space Telescope, a flagship project expected to launch in 2021. Congress has previously intervened in similar requests.

The senators’ bill also orders NASA to launch an infrared asteroid-hunting space telescope to operate in space by 2025. NASA already announced its intention to do so in September, with an instrument based on the previously proposed mission.

The act would also require NASA to develop a plan by the end of 2021 to test a new type of propulsion — nuclear thermal propulsion — in flight in 2024. This technology has the potential to cut travel times across the solar system, which is relevant for NASA’s hopes to land humans on Mars in 2033 or 2035.

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Scientists may have discovered whole new class of black holes

A new study has found that researchers may have missed a whole category of black holes which they did not know actually existed during their search.

Lead author of the study Todd Thompson along with other researchers began analysing APOGEE (Apache Point Observatory Galactic Evolution Experiment) data, which gathered light spectra radiated from about 100,000 stars in the Milk Way. They looked for the stars which showed a change in their spectra, hinting that they may be orbiting around one black hole. Next, the researchers narrowed down the data from APOGEE to 200 stars which were believed to be most fascinating. The findings showed a huge red color star orbiting around something, which was tinier than the black holes known in the Universe, but way larger than most of the neutron stars known.

After further calculations and with the help of a few additional data, they realized that they discovered one low-mass black hole, around 3.3 times larger than the sun.

In the study, astronomers have offered an all new way for searching black holes, and reveal that there’s a possibility for a new category of black holes tinier than the tiniest black holes known in the Universe.

As per Thompson, through the study, they are revealing a hint that there’s a new population in the Universe which they are yet to investigate in the hunt for black holes.

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Science/Astronomy

Origin of modern humans ‘traced to Botswana’

Scientists believe they have traced humans’ ancestral home to a wetland that existed in what is now Botswana.

The region, south of the Zambezi River, became a home for Homo sapiens some 200,000 years ago and provided space for a founding population of humans for some 70,000 years, according to scientists.

“We have known for a long time that modern humans originated in Africa and roughly 200,000 years ago, but what we hadn’t known until this study was where exactly,” Vanessa Hayes, a geneticist and senior author on the new study at the Garvan Institute of Medical Research in Sydney, told The Guadian.

For their study published on Monday, the researchers used mitochondrial DNA, which is passed down from mother to child, to determine the oldest known maternal line of humans.

Their conclusions, which have reportedly not been embraced by some experts, are based on an analysis of 1,217 samples of mitochondrial DNA.

I’m definitely cautious about using modern genetic distributions to infer exactly where ancestral populations were living 200,000 years ago, particularly in a continent as large and complex as Africa,” Chris Stringer, who studies human origins at the Natural History Museum in London, told The Guardian.

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Asteroid Hygiea could become the tiniest dwarf planet

As the debate rages on whether Pluto, currently a dwarf planet, should be given back its planet status, it may soon be joined by an asteroid that could wind up being the smallest dwarf planet in the solar system.

Asteroid Hygiea, the fourth largest space rock in the Asteroid Belt, was observed for the first time by astronomers in high-resolution. It’s spherical in shape and may wind up taking the crown for the smallest dwarf from Ceres, also located in the Asteroid Belt.

“Thanks to the unique capability of the SPHERE instrument on the [Very Large Telescope], which is one of the most powerful imaging systems in the world, we could resolve Hygiea’s shape, which turns out to be nearly spherical,” said the study’s lead author, Pierre Vernazza, in a statement. “Thanks to these images, Hygiea may be reclassified as a dwarf planet, so far the smallest in the Solar System.”

“By comparing Hygiea’s sphericity with that of other Solar System objects, it appears that Hygiea is nearly as spherical as Ceres, opening up the possibility for this object to be reclassified as a dwarf planet,” the study’s abstract states.

In addition to the spherical requirement for dwarf planet status, Hygiea already orbits the Sun, is not a moon, and has “not cleared the neighborhood around its orbit,” the ESO added in its statement.

The research has been published in the scientific journal Nature Astronomy.

Though Hygiea may eventually be given dwarf planet status, it’s significantly smaller than Pluto or Ceres, with a diameter of just 267 miles. Pluto’s diameter is approximately 1,490 miles, while Ceres’ diameter is approximately 590 miles.

Following the discovery, the International Astronomical Union will eventually vote to determine whether Hygiea can be given dwarf planet status or if it will remain an asteroid.

Earlier this month, NASA Administrator Jim Bridenstine said at the International Astronautical Congress that Pluto should be given back its planet status. “I am here to tell you, as the NASA Administrator, I believe Pluto should be a planet,” he said to applause during a wide-ranging speech.

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NASA confirms plans to send prospecting rover to the moon

WASHINGTON — NASA Administrator Jim Bridenstine announced Oct. 25 that the agency would send a robotic rover to the moon in 2022 to look for water ice, confirming plans that had been taking shape for months.

In a speech at the 70th International Astronautical Congress, Bridenstine said the Volatiles Investigating Polar Exploration Rover (VIPER) mission would look for ice on or below the surface of the moon at its south pole, a key resource for future human missions.

“We actually have a mission right now that I’m very pleased to announce, it’s called VIPER,” he said. VIPER would fly to a moon on a commercial lander through the agency’s Commercial Lunar Payload Services (CLPS) program.

“VIPER is going to rover on the south pole of the moon and VIPER is going to assess where the water ice is,” he continued. “We’re going to characterize the water ice, and ultimately drill and find out just how the water ice is embedded in the regolith on the moon.”

Bridenstine and others have long trumpeted the presence of potentially hundreds of millions of tons water ice on the moon as a key reason human missions should go to the lunar poles. However, there’s little “ground truth” about that water ice, including exactly where it is located and in what concentrations, as well as how difficult it would be to extract that water ice.

The $250 million VIPER mission would launch in late 2022 and operate at the south pole of the moon for 100 days. The rover will use a neutron spectrometer to detect potential ice deposits below the surface, then access them with a drill than can go as deep as one meter into the surface. Subsurface samples retrieved by the drill would then be examined by a mass spectrometer and near-infrared spectrometer.

“It’s incredibly exciting to have a rover going to the new and unique environment of the south pole to discover where exactly we can harvest that water,” said Anthony Colaprete, VIPER project scientist, in a NASA statement. “VIPER will tell us which locations have the highest concentrations and how deep below the surface to go to get access to water.”

While Bridenstine announced the mission in that speech, agency officials have been discussing plans for VIPER in industry forums for several months. The rover is intended to be part of a “mobility strategy” for lunar exploration, Steve Clarke, deputy associate administrator for exploration in NASA’s Science Mission Directorate (SMD), said at the NASA Exploration Science Forum in July.

NASA had been studying another rover mission for several years, called Resource Prospector. However, the agency cancelled the mission in 2018, arguing that the agency could instead fly instruments from the rover on CLPS landers.

VIPER “heavily leverages the Resource Prospector engineering that we’re in the process of archiving now,” said Jay Jenkins, program executive in SMD’s Office of Exploration, during a panel at the Wernher von Braun Memorial Symposium in September. “But unlike Resource Prospector, we’re going to be delivering that on a CLPS lander.”

Another key difference is mission duration. Resource Prospector was intended to last just 14 days, while VIPER’s mission is currently slated for 100 days. VIPER will take advantage of locations near the south pole that are in sunlight for most of a lunar day to enable that extended mission.

Jenkins acknowledged last month that the agency had a “very aggressive schedule” to get the mission launched by the end of 2022. “In order to do that, we are employing efficient processes,” he said, such as those for the Lunar Crater Observation and Sensing Satellite (LCROSS) mission that impacted the moon in 2009 as part to search for water and other volatiles, a mission that went from “cradle to grave within two years.” Like Resource Prospector and LCROSS, VIPER will be managed by NASA’s Ames Research Center.

VIPER, described as the size of as golf cart, is too large to be carried to the moon on most CLPS landers currently under contract with NASA. The agency recently held an “on ramp” to the program, seeking proposals for landers with enhanced landing capability capable of placing several hundred kilograms of payloads on the surface. Proposals for that CLPS on ramp were due to NASA in September, and the agency expects to select one or more companies by the end of the year.