Connect with us

Science

U.S.-Russian crew launches to International Space Station for 6 month stay

Published

 on

A trio of space travelers launched successfully to the International Space Station, for the first time using a fast-track maneuver to reach the orbiting outpost in just three hours.

NASA’s Kate Rubins along with Sergey Ryzhikov and Sergey Kud-Sverchkov of the Russian space agency Roscosmos lifted off as scheduled Wednesday morning from the Russia-leased Baikonur space launch facility in Kazakhstan for a six-month stint on the station.

For the first time, they tried a two-orbit approach and docked with the space station in just a little over three hours after lift-off. Previously it took twice as long for crews to reach the station.

They will join the station’s NASA commander, Chris Cassidy, and Roscosmos cosmonauts Anatoly Ivanishin and Ivan Vagner, who have been aboard the complex since April and are scheduled to return to Earth in a week.

Speaking during Tuesday’s pre-launch news conference at Baikonur, Rubins emphasized that the crew spent weeks in quarantine at the Star City training facility outside Moscow and then on Baikonur to avoid any threat from the coronavirus.

“We spent two weeks at Star City and then 17 days at Baikonur in a very strict quarantine,” Rubins said. “During all communications with crew members, we were wearing masks. We made PCR tests twice and we also made three times antigen fast tests.”

She said she was looking forward to scientific experiments planned for the mission.

“We’re planning to try some really interesting things like bio-printing tissues and growing cells in space and, of course, continuing our work on sequencing DNA,” Rubins said.

Ryzhikov, who will be the station’s skipper, said the crew will try to pinpoint the exact location of a leak at a station’s Russian section that has slowly leaked oxygen. The small leak hasn’t posed any immediate danger to the crew.

“We will take with us additional equipment which will allow us to detect the place of this leak more precisely,” he told reporters. “We will also take with us additional improved hermetic material which will allow to fix the leak.”

In November, Rubins, Ryzhikov and Kud-Sverchkov are set to greet NASA’s SpaceX first operational Crew Dragon mission, bringing NASA astronauts Mike Hopkins, Victor Glover and Shannon Walker, and Japan Aerospace Exploration Agency astronaut Soichi Noguchi to the space station aboard the Crew Dragon vehicle. It follows a successful Demo-2 mission earlier this year.

The Crew Dragon mission was pushed back from Oct. 31 into November, and no new date has been set yet. The delay is intended to give SpaceX more time to conduct tests and review data from an aborted Falcon 9 launch earlier this month.

 

Source:

Source link

Continue Reading

Science

Scientists Peer Inside an Asteroid – Is Bennu in the Process of Spinning Itself Into Pieces? – SciTechDaily

Published

 on


OSIRIS REx Arrives at Asteroid Bennu

This series of images taken by the OSIRIS-REx spacecraft shows Bennu in one full rotation from a distance of around 50 miles (80 km). The spacecraft’s PolyCam camera obtained the thirty-six 2.2-millisecond frames over a period of four hours and 18 minutes. Credit: NASA’s Goddard Space Flight Center/University of Arizona

New findings from NASA’s OSIRIS-REx mission suggest that the interior of the asteroid Bennu could be weaker and less dense than its outer layers—like a crème-filled chocolate egg flying though space.

The results appear in a study published in the journal Science Advances and led by the University of Colorado Boulder’s OSIRIS-REx team, including professors Daniel Scheeres and Jay McMahon. The findings could give scientists new insights into the evolution of the solar system’s asteroids—how bodies like Bennu transform over millions of years or more.  

OSIRIS-REx rendezvoused with Bennu, an asteroid orbiting the sun more than 200 million miles from Earth, in late 2018. Since then, the spacecraft, built by Colorado-based Lockheed Martin, has studied the object in more detail than any other asteroid in the history of space exploration.

So far, however, one question has remained elusive: What’s Bennu like on the inside?

Bennu Orbit Diagram

Diagram of the orbit of Bennu in relation to Earth and other planets. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

Scheeres, McMahon and their colleagues on the mission’s radio science team now think that they have an answer—or at least part of one. Using OSIRIS-REx’s own navigational instruments and other tools, the group spent nearly two years mapping out the ebbs and flows of Bennu’s gravity field. Think of it like taking an X-ray of a chunk of space debris with an average width about the height of the Empire State Building.

“If you can measure the gravity field with enough precision, that places hard constraints on where the mass is located, even if you can’t see it directly,” said Andrew French, a coauthor of the new study and a former graduate student at CU Boulder, now at NASA’s Jet Propulsion Laboratory (JPL).

What the team has found may also spell trouble for Bennu. The asteroid’s core appears to be weaker than its exterior, a fact that could put its survival at risk in the not-too-distant future.

“You could imagine maybe in a million years or less the whole thing flying apart,” said Scheeres, a distinguished professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences.

Evolution of asteroids

Of course, that’s part of the fun of studying asteroids. Scheeres explained that Bennu belongs to a class of smaller bodies that scientists call “rubble pile” asteroids—which, as their name suggests, resemble loosely held-together mounds of debris. 

Asteroids also change over time more than people think. 

“None of them have sat out there unchanging since the dawn of the solar system,” Scheeres said. “They’re being changed by things like sunlight affecting how they spin and collisions with other asteroids.”

To study how Bennu and other similar asteroids may change, however, he and his colleagues needed to take a peek inside.

Asteroid Bennu Particles

OSIRIS-REx observed small bits of material leaping off the surface of the asteroid Bennu on January 19, 2019. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

This is where the team got lucky. When OSIRIS-REx first arrived at Bennu, the spacecraft spotted something unusual: Over and over again, tiny bits of material, some just the size of marbles, seemed to pop off the asteroid and into space. In many cases, those particles circled Bennu before falling back down to the surface. Members of the mission’s radio science team at JPL were able to witness how the body’s gravity worked first-hand—a bit like the apocryphal story of Isaac Newton inferring the existence of gravity after observing an apple falling on his head. 

“It was a little like someone was on the surface of the asteroid and throwing these marbles up so they could be tracked,” Scheeres said. “Our colleagues could infer the gravity field in the trajectories those particles took.”

Squishy center

In the new study, Scheeres and his colleagues combined those records of Bennu’s gravity at work with data from OSIRIS-REx itself—precise measurements of how the asteroid tugged on the spacecraft over a period of months. They discovered something surprising: Before the mission began, many scientists had assumed that Bennu would have a homogenous interior. As Scheeres put it, “a pile of rocks is a pile of rocks.” 

But the gravity field measurements suggested something different. To explain those patterns, certain chunks of Bennu’s interior would likely need to be more tightly packed together than others. And some of the least dense spots in the asteroid seemed to lie around the distinct bulge at its equator and at its very core.

“It’s as if there is a void at its center, within which you could fit a couple of football fields,” Scheeres said.

[embedded content]
Now, thanks to laser altimetry data and high-resolution imagery from OSIRIS-REx, we can take a tour of Bennu’s remarkable terrain. Credit: NASA’s Goddard Space Flight Center

The asteroid’s spin may be responsible for that void. Scientists know that the asteroid is spinning faster and faster over time. That building momentum could, Scheeres said, be slowly pushing material away from the asteroid’s center and toward its surface.  Bennu, in other words, may be in the process of spinning itself into pieces.

“If its core has a low density, it’s going to be easier to pull the entire asteroid apart,” Scheeres said.

For the scientist, the new findings are bittersweet: After measuring Bennu’s gravity field, Scheeres and his team have mostly wrapped up their work on the OSIRIS-REx mission. 

Their results have contributed to the mission’s sample analysis plan—currently in development. The returned sample will be analyzed to determine the cohesion between grains—a key physical property that affects the mass distribution observed in their study.

“We were hoping to find out what happened to this asteroid over time, which can give us better insight into how all of these small asteroids are changing over millions, hundreds of millions or even billions of years,” Scheeres said. “Our findings exceeded our expectations.”

Read Asteroid Bennu Secrets Unlocked by NASA’s OSIRIS-REx Ahead of Historic Heist for more on this and related research.

“Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu” by D. J. Scheeres, A. S. French, P. Tricarico, S. R. Chesley, Y. Takahashi, D. Farnocchia, J. W. McMahon, D. N. Brack, A. B. Davis, R.-L. Ballouz, E. R. Jawin, B. Rozitis, J. P. Emery, A. J. Ryan, R. S. Park, B. P. Rush, N. Mastrodemos, B. M. Kennedy, J. Bellerose, D. P. Lubey, D. Velez, A. T. Vaughan, J. M. Leonard, J. Geeraert, B. Page, P. Antreasian, E. Mazarico, K. Getzandanner, D. Rowlands, M. C. Moreau, J. Small, D. E. Highsmith, S. Goossens, E. E. Palmer, J. R. Weirich, R. W. Gaskell, O. S. Barnouin, M. G. Daly, J. A. Seabrook, M. M. Al Asad, L. C. Philpott, C. L. Johnson, C. M. Hartzell, V. E. Hamilton, P. Michel, K. J. Walsh, M. C. Nolan and D. S. Lauretta, 8 October 2020, Science Advances.
DOI: 10.1126/sciadv.abc3350

The University of Arizona leads science operations for OSIRIS-REx. NASA’s Goddard Space Flight Center in Maryland manages the overall mission.

Other coauthors on the new study include researchers at the Jet Propulsion Laboratory, Smithsonian Institution, The Open University, Northern Arizona University, KinetX Aerospace, Inc., NASA Goddard Space Flight Center, University of Maryland, Johns Hopkins University, York University, University of British Columbia, Southwest Research Institute, Université Côte d’Azur and University of Arizona.

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Geologists might have found a long-lost tectonic plate – Tech Explorist

Published

 on


Jonny Wu and Spencer Fuston
Jonny Wu (left), assistant professor of geology in the UH Department of Earth and Atmospheric Sciences, and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era.

The existence of a tectonic plate called Resurrection has long been controversial among geophysicists. Some believe that it never existed, while others say that it is subducted into the Earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.

A new study by the University of Houston College of Natural Sciences and Mathematics shed light on this- suggesting that the Resurrection plate existed. Scientists believe they have found the remains of the missing plate, Resurrection in northern Canada-crushed, reshaped, and buried through subduction processes.

For this study, scientists used a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era.

D block diagram across North America showing a mantle tomography image
A 3D block diagram across North America showing a mantle tomography image reveals the Slab Unfolding method used to flatten the Farallon tectonic plate. By doing this, Fuston and Wu were able to locate the lost Resurrection plate.

The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates, and geologists have always known there were two plates in the Pacific Ocean around then called Kula and Farallon. Be that as it may, there has been discussion about a potential third plate, Resurrection, which has shaped a unique volcanic belt along with Alaska and Washington State.

According to scientists, this study could help geologists predict volcanic hazards and mineral and hydrocarbon deposits.

 plate tectonic reconstruction
This image shows plate tectonic reconstruction of western North America 60 million years ago showing subduction of three key tectonic plates, Kula, Farallon and Resurrection.

Spencer Fuston, a third-year geology doctoral student, said, “We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data support.”

Using 3-D mapping technology, scientists applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.

[embedded content]

Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences, said, “When ‘raised’ back to the Earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record.”

Journal Reference:
  1. Spencer Fuston et al., Raising the Resurrection plate from an unfolded-slab plate tectonic reconstruction of northwestern North America since early Cenozoic time, GSA Bulletin (2020). DOI: 10.1130/B35677.1

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Researchers rediscover tectonic plate lost for 60 million years – lintelligencer

Published

 on


Researchers rediscover tectonic plate lost for 60 million years

The existence of a tectonic plate called Resurrection has long been a topic of debate among geologists, with some arguing it was never real. Others say it subducted – moved sideways and downward – into the earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.

A team of geologists at the University of Houston College of Natural Sciences and Mathematics believes they have found the lost plate in northern Canada by using existing mantle tomography images – similar to a CT scan of the earth’s interior. The findings, published in Geological Society of America Bulletin, could help geologists better predict volcanic hazards as well as mineral and hydrocarbon deposits.

“Volcanoes form at plate boundaries, and the more plates you have, the more volcanoes you have,” said Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences. “Volcanoes also affect climate change. So, when you are trying to model the earth and understand how climate has changed since time, you really want to know how many volcanoes there have been on earth.”

Wu and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era. The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates and geologists have always known there were two plates in the Pacific Ocean at that time called Kula and Farallon. But there has been discussion about a potential third plate, Resurrection, having formed a special type of volcanic belt along Alaska and Washington State.

“We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data supports,” Fuston said.

Using 3D mapping technology, Fuston applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.

“When ‘raised’ back to the earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record,” explained Wu.

[embedded content]

Let’s block ads! (Why?)



Source link

Continue Reading

Trending