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Spacewalking astronauts complete a space station battery upgrade years in the making – Space.com

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Two NASA astronauts completed the second in a pair of spacewalks today (Feb. 1), installing a European science platform and finishing up a long series of battery replacements outside the International Space Station

Today’s spacewalk, which began at 7:56 a.m. EST (1256 GMT), was the 234th spacewalk, or extravehicular activity (EVA), in support of space station assembly, maintenance and upgrades, according to NASA. The 233rd spacewalk took place just a few days prior, on Jan. 27.

This spacewalk was conducted by NASA astronaut Victor Glover and NASA astronaut Mike Hopkins. This marked Glover’s second spacewalk and Hopkin’s fourth spacewalk.

“Enjoying the view,” Hopkins said about the view of the Earth from space during the spacewalk.

Related: The International Space Station: inside and out (infographic) 

NASA astronaut Victor Glover rides on Canadarm2 to complete work during a spacewalk on Feb. 1, 2021.  (Image credit: NASA)

Glover and Hopkins had a variety of tasks to tackle when they stepped out into space. After completing their main objectives — which included configuring a battery and adapter plate and installing three separate cameras — just about four hours into what was planned to be a six-and-a-half-hour spacewalk, the astronauts were able to complete some “get-ahead” activities.

“We went out the door a little bit late today but we’ve made up all that time,” Hopkins said during the spacewalk.

The pair was assisted by personnel including NASA astronaut Kate Rubins and Japan Aerospace Exploration Agency (JAXA) astronaut Soichi Noguchi on board the space station and NASA astronaut Bob Hines, who relayed next steps to the spacewalkers from the ground. 

Throughout the duration of the mission, Glover used the “call sign,” or nickname, of “Ike, Hopkins used the name “Hopper” and Hines went by “Farmer.”

First, after leaving the space station airlock, Glover and Hopkins installed the final lithium-ion battery and adapter plate on the port 4 (P4) truss. The adapter plate completed the circuit for the battery system. This was the last in a series of battery-installment EVA activities that began in January 2017 to replace old nickel-hydrogen batteries with new lithium-ion batteries. Hopkins installed a scoop, a handling aid, on the lithium-ion battery to help with the installation.

“Final adapter plate installed on the @Space_Station. Today’s spacewalk will wrap up battery replacement work to change out batteries for 8 power channels used to route electricity on the station. Upgrades have been carried out in a series of spacewalks over the past 4 years,” NASA tweeted about the accomplishment.

“1 hr into today’s spacewalk and we have confirmation that the final Li-ion battery installed has a good configuration. @AstroVicGlover and @Astro_Illini are continuing to work on their tasks on the station,” NASA confirmed in another tweet

The astronauts then drilled one bolt to secure the Direct Current Switching Unit (DCSU), which helps to route power through the station’s battery system. 

Following the completion of this main task, Hopkins worked to remove the H-fixture, a grapple fixture bracket on the same truss as the battery that were once used for ground processing of solar arrays and are not needed any longer. Hopkins loosened and removed four bolts using a tool on a retractable tether. These fixtures are necessary for future power upgrades, NASA commentator Leah Cheshier noted during the agency’s broadcast.

NASA astronauts Victor Glover and Mike Hopkins completed the second in a series of two spacewalks today Feb. 1, 2021.  (Image credit: NASA)

Glover next began replacing a magenta-hued camera on the starboard truss; the camera’s color wheel had broken. To do this, Glover had to ride the station’s robotic arm, Canadarm2, over to the area. The arm, which provides added stability during the maneuver, was robotically controlled by Rubins from the space station. 

To get onto the arm to “ride” it to the site, Glover had to attach and configure an articulating, portable foot restraint that would connect his feet to the arm. Before the maneuver, Hopkins did a quick helmet absorption pad (HAP) check to make sure nothing was leaking inside the suit.

Once secure on the arm, and with help from Rubins inside the orbiting laboratory, Glover “flew” over to the camera’s site, with the blue hues of the Atlantic Ocean swirling hazily below. Glover successfully replaced the broken camera on the starboard truss, the first of three cameras to be installed during the spacewalk. To do this, Glover used a pistol grip tool (PGT), which astronauts use to remove and install bolts during spacewalks. 

Next, as the crew flew into orbital nighttime, Hopkins and Glover moved to work on two other camera systems on the space station. The pair worked to install a new HD camera on the U.S. Destiny laboratory module and then Hopkins worked to replace pieces of the camera system on the remote manipulator system on the Japanese robotic arm. 

Glover then moved to exit the foot restraint on Canadarm2, jokingly saying, “I’d fly with ‘Air Rubins’ anytime,” as astronaut Rubins commanded the arm as he rode it. 

At this point, just about four hours into the spacewalk, the astronauts had completed all major tasks set out for the event and moved on to “get ahead” tasks, or extra objectives that would otherwise be done during a later spacewalk. 

During this final stretch of the spacewalk, Hopkins removed an additional H-fixture and took photos of the space station’s exterior to document its current state. Glover prepared the foot restraint configuration (that he earlier used for the robotic arm ride) for a future spacewalk. Glover also removed and replaced an airlock magnet, a metal plate that helps to keep the thermal cover on the space station’s Quest Joint Airlock closed.

NASA astronaut Kate Rubins (right) and JAXA astronaut Soichi Noguchi (left) watch and wait for NASA astronauts Mike Hopkins and Victor Glover to return from a spacewalk on Feb. 1, 2021.  (Image credit: NASA)

Five hours and 20 minutes after they began, at 1:16 p.m. EST (1816 GMT), the astronauts began repressurizing the airlock and the spacewalk was officially over. 

“Just want to say thank you to the entire … Farmer and vincent and everybody else, well done … i think we had a very very very good day … Thanks to everyone,” Hopkins said as the spacewalk ended.

Following today’s spacewalk, the Expedition 64 astronauts will conduct two additional spacewalks in the near future, according to NASA. Next, Glover and Rubins will prepare the space station’s power system for the installation of new solar arrays and, in the spacewalk after that, Rubins and Noguchi will continue to upgrade space station components, according to NASA. The exact dates for those spacewalks have not yet been set. 

Today’s spacewalk coincides with the first day of Black History Month. Glover, who completed today’s spacewalk with Hopkins, is the first Black astronaut to take part in a long-duration mission on the station, staying for over six months as part of Expedition 64 and Expedition 65. Glover, who launched to the space station on Nov. 15, 2020, as part of SpaceX’s Crew-1 mission, is only the 15th Black astronaut to ever reach space.

“It is something to be celebrated once we accomplish it, and, you know, I am honored to be in this position and to be a part of this great and experienced crew,” Glover said during a 2020 news conference before he launched to the space station. “And I look forward to getting up there and doing my best to make sure that, you know, we are worthy of all the work that’s been put into setting us up for this mission.”

This spacewalk also coincides with the anniversary of the loss of STS-107, the Space Shuttle Columbia mission that, on Feb. 1, 2003, ended in tragedy the shuttle broke up while returning to Earth, killing all seven astronauts on board: Rick Husband, Michael Anderson, David Brown, Kalpana Chawla, Laurel Clark, William McCool and Ilan Ramon. The crew had successfully made it to space, where they spent 16 days and performed about 80 experiments before attempting to return to Earth. 

An investigation determined that during launch, a large piece of foam fell from the shuttle’s external tank and hit the spacecraft’s wing. That damage caused the shuttle’s reentry failure. This tragic event moved NASA to take a hard look at their safety protocols and internal workplace culture to prioritize future astronaut safety. 

Email Chelsea Gohd at cgohd@space.com or follow her on Twitter @chelsea_gohd. Follow us on Twitter @Spacedotcom and on Facebook.

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NASA Moves Forward With Next-Gen Solar Sail Project – ExtremeTech

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Getting from point A to point B in the solar system is no simple feat, and inefficient, heavy rockets aren’t always the best way. Therefore, NASA has announced it is moving ahead with a new solar sail concept that could make future spacecraft more efficient and maneuverable. The Diffractive Solar Sailing project is now entering phase III development under the NASA Innovative Advanced Concepts (NIAC) program, which could eventually lead to probes that use solar radiation to coast over the sun’s polar regions. 

The concept of solar sails is an old one — they were first proposed in the 1980s. The gist is that you equip a vessel with a lightweight sail that translates the pressure from solar radiation into propulsion. The problem is that a solar sail has to be much larger than the spacecraft it’s dragging along. Even a low-thrust solar sail would need to be almost a square kilometer, and you need to keep it intact over the course of a mission. Plus, you have little choice but to fly in the direction of sunlight, so you have to make tradeoffs for either power or navigation. Futuristic diffractive light sails could address these shortcomings. 

This work is being undertaken at the Johns Hopkins University Applied Physics Laboratory under the leadership of Amber Dubill and co-investigator Grover Swartzlander. The project progressed through phase I and II trials, which had the team developing concept and feasibility studies on diffractive light sails. The phase III award ensures $2 million in funding over the next two years to design and test the materials that could make diffractive light propulsion a reality. 

A standard lightsail developed by the Planetary Society in 2019.

A diffractive light sail, as the name implies, takes advantage of a property of light known as diffraction. When light passes through a small opening, it spreads out on the other side. This could be used to make a light sail more maneuverable so it doesn’t need to go wherever the solar winds blow. 

The team will design its prototypes with several possible mission applications in mind. This technology most likely won’t have an impact on missions to the outer solar system where sunlight is weaker and the monumental distances require faster modes of transportation. However, heliophysics is a great use case for diffractive lightsailing as it would allow visiting the polar regions of the sun, which are difficult to access with current technology.

A lightsail with the ability to essentially redirect thrust from a continuous stream of sunlight would be able to enter orbit over the poles. It may even be possible to maneuver a constellation of satellites into this difficult orbit to study the sun from a new angle. In a few years, NASA may be able to conduct a demonstration mission. Until then, it’s all theoretical.

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Tau Herculid meteor shower will happen Monday night, Tuesday morning – USA TODAY

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461 new objects discovered at the edge of our solar system

It increases our knowledge of what’s floating in the Kuiper Belt by a significant margin.

Buzz60, Buzz60

  • The meteor shower, known as the tau Herculids, could be spectacular, or it could be a total dud.
  • If it does reach thousands of meteors per hour, it would be a “meteor storm.”
  • Maximum activity is expected around 1 a.m. EDT Tuesday morning, May 31.

Sky watchers could be in for a memorable spectacle Monday night and early Tuesday morning as the Earth passes through debris from a disintegrating comet, leading to a potential meteor shower with thousands of shooting stars per hour. 

The meteor shower, known as the tau Herculids, could be spectacular, or it could be a total dud, astronomers said.  

“This is going to be an all or nothing event,” NASA meteor expert Bill Cooke said in a statement. If it does reach thousands of meteors per hour, it would be a “meteor storm,” as opposed to a shower.

There is “a small chance of something extraordinary – perhaps one of the most dramatic meteor displays since the spectacular Leonid meteor showers of more than 20 years ago,” said Joe Rao of Space.com

Maximum activity is expected around 1 a.m. EDT Tuesday, the Space Weather Archive blog said. 

The comet is known as 73P/Schwassmann-Wachmann 3 (SW3), named after the two German astronomers who discovered it in 1930. The comet is breaking into dozens of pieces as it orbits the sun, which it does every 5.4 years, NASA said. 

EYE TO THE SKY: How to watch every meteor shower in 2022

In all, SW 3 has broken into more than 68 fragments. At its most recent appearance in March 2017, it showed signs that it sheds pieces in each return through the inner solar system, Rao said. 

If it makes it to us this year, the debris from the comet will strike Earth’s atmosphere at 10 miles per second, which is on the slow side for a good meteor shower. 

Stargazers will pay attention this year because meteors should be high in the night sky at the forecast peak time, NASA said. The higher the radiant point is in the sky, the more meteors you are likely to see.

Even better, the moon is new, so there will be no moonlight to wash out the faint meteors.

For ideal viewing of this or any meteor shower, find a spot away from city lights. Your eyes will need to adjust to the darkness, which could take 15 to 20 minutes. Watching meteor showers can take time, so be patient, experts advise. It could be worth the wait!

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Toward customizable timber, grown in a lab – EurekAlert

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image: In an effort to provide an environmentally friendly and low-waste alternative, researchers at MIT have pioneered a tunable technique to generate wood-like plant material in a lab.
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Credit: Image courtesy of Luis Fernando Velásquez-García, Ashley Beckwith, et al

Each year, the world loses about 10 million hectares of forest — an area about the size of Iceland — because of deforestation. At that rate, some scientists predict the world’s forests could disappear in 100 to 200 years.

In an effort to provide an environmentally friendly and low-waste alternative, researchers at MIT have pioneered a tunable technique to generate wood-like plant material in a lab, which could enable someone to “grow” a wooden product like a table without needing to cut down trees, process lumber, etc.

These researchers have now demonstrated that, by adjusting certain chemicals used during the growth process, they can precisely control the physical and mechanical properties of the resulting plant material, such as its stiffness and density.

They also show that, using 3D bioprinting techniques, they can grow plant material in shapes, sizes, and forms that are not found in nature and that can’t be easily produced using traditional agricultural methods.

“The idea is that you can grow these plant materials in exactly the shape that you need, so you don’t need to do any subtractive manufacturing after the fact, which reduces the amount of energy and waste. There is a lot of potential to expand this and grow three-dimensional structures,” says lead author Ashley Beckwith, a recent PhD graduate.

Though still in its early days, this research demonstrates that lab-grown plant materials can be tuned to have specific characteristics, which could someday enable researchers to grow wood products with the exact features needed for a particular application, like high strength to support the walls of a house or certain thermal properties to more efficiently heat a room, explains senior author Luis Fernando Velásquez-García, a principal scientist in MIT’s Microsystems Technology Laboratories.

Joining Beckwith and Velásquez-García on the paper is Jeffrey Borenstein, a biomedical engineer and group leader at the Charles Stark Draper Laboratory. The research is published today in Materials Today.

Planting cells

To begin the process of growing plant material in the lab, the researchers first isolate cells from the leaves of young Zinnia elegans plants. The cells are cultured in liquid medium for two days, then transferred to a gel-based medium, which contains nutrients and two different hormones.

Adjusting the hormone levels at this stage in the process enables researchers to tune the physical and mechanical properties of the plant cells that grow in that nutrient-rich broth.

“In the human body, you have hormones that determine how your cells develop and how certain traits emerge. In the same way, by changing the hormone concentrations in the nutrient broth, the plant cells respond differently. Just by manipulating these tiny chemical quantities, we can elicit pretty dramatic changes in terms of the physical outcomes,” Beckwith says.

In a way, these growing plant cells behave almost like stem cells — researchers can give them cues to tell them what to become, Velásquez-García adds.

They use a 3D printer to extrude the cell culture gel solution into a specific structure in a petri dish, and let it incubate in the dark for three months. Even with this incubation period, the researchers’ process is about two orders of magnitude faster than the time it takes for a tree to grow to maturity, Velásquez-García says.

Following incubation, the resulting cell-based material is dehydrated, and then the researchers evaluate its properties.

Wood-like characteristics

They found that lower hormone levels yielded plant materials with more rounded, open cells that have lower density, while higher hormone levels led to the growth of plant materials with smaller, denser cell structures. Higher hormone levels also yielded plant material that was stiffer; the researchers were able to grow plant material with a storage modulus (stiffness) similar to that of some natural woods.

Another goal of this work is to study what is known as lignification in these lab-grown plant materials. Lignin is a polymer that is deposited in the cell walls of plants which makes them rigid and woody. They found that higher hormone levels in the growth medium causes more lignification, which would lead to plant material with more wood-like properties.

The researchers also demonstrated that, using a 3D bioprinting process, the plant material can be grown in a custom shape and size. Rather than using a mold, the process involves the use of a customizable computer-aided design file that is fed to a 3D bioprinter, which deposits the cell gel culture into a specific shape. For instance, they were able to grow plant material in the shape of a tiny evergreen tree.

Research of this kind is relatively new, Borenstein says.

“This work demonstrates the power that a technology at the interface between engineering and biology can bring to bear on an environmental challenge, leveraging advances originally developed for health care applications,” he adds.

The researchers also show that the cell cultures can survive and continue to grow for months after printing, and that using a thicker gel to produce thicker plant material structures does not impact the survival rate of the lab-grown cells.

“Amenable to customization”

“I think the real opportunity here is to be optimal with what you use and how you use it. If you want to create an object that is going to serve some purpose, there are mechanical expectations to consider. This process is really amenable to customization,” Velásquez-García says.

Now that they have demonstrated the effective tunability of this technique, the researchers want to continue experimenting so they can better understand and control cellular development. They also want to explore how other chemical and genetic factors can direct the growth of the cells.

They hope to evaluate how their method could be transferred to a new species. Zinnia plants don’t produce wood, but if this method were used to make a commercially important tree species, like pine, the process would need to be tailored to that species, Velásquez-García says.  

Ultimately, he is hopeful this work can help to motivate other groups to dive into this area of research to help reduce deforestation.

“Trees and forests are an amazing tool for helping us manage climate change, so being as strategic as we can with these resources will be a societal necessity going forward,” Beckwith adds.

This research is funded, in part, by the Draper Scholars Program.

###

Written by Adam Zewe, MIT News Office

Additional background

Paper: “Physical, mechanical, and microstructural characterization of novel, 3D-printable, tunable, lab-grown plant materials generated from Zinnia elegans cell cultures”

https://www.sciencedirect.com/science/article/pii/S1369702122000451


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