Avaruus

Normally, big volcanic eruptions release large amounts of ash and gases, such as sulfur dioxide, which can create reflective compounds in the atmosphere. These volcanic byproducts can block sunlight from reaching the planet's surface, which can cool the atmosphere. However, the Tonga eruption produced surprisingly low levels of sulfur dioxide compared with similarly sized explosions, and most of the ash it ejected quickly fell to the ground.

As a result, experts initially estimated that the underwater explosion would have minimal effects on Earth's climate (opens in new tab). But these estimates were based on the amount of ash and gases that the volcano emitted and did not account for all of the excess water vapor, which could be just as problematic.

This excess water, the researchers warned, could have a radiating effect that could warm the atmosphere much as greenhouse gases (opens in new tab) do. Because the water is likely to stick around longer than other volcanic gases, like sulfur dioxide — which normally fall out of the atmosphere within two to three years — the water's warming effect will likely outlast any cooling effects the gases create.

This means the Tonga explosion will likely be the first eruption on record to cause a warming effect, rather than a cooling effect, on the planet, researchers wrote.
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www.space.com

Tonga's eruption injected so much water into Earth's atmosphere that it could weaken the ozone layer

The atmospheric water vapor could also contribute to global warming.
www.space.com www.space.com
The researchers also pointed out that such a sharp increase in water vapor could decrease the amount of ozone in the stratosphere, thus potentially weakening the ozone layer that protects life on Earth from damaging ultraviolet radiation from the sun. Stratospheric water, or H2O, can break down into OH ions over time. Those ions could react with ozone, which is made of three oxygen atoms, to create water and oxygen. However, it is unclear how this will affect the ozone layer as a whole, researchers wrote.
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A new analysis of seismic data from NASA's Mars InSight mission has revealed a couple of surprises.

The first surprise: the top 300 meters of the subsurface beneath the landing site near the Martian equator contains little or no ice.

"We find that Mars' crust is weak and porous. The sediments are not well-cemented. And there's no ice or not much ice filling the pore spaces," said geophysicist Vashan Wright of Scripps Institution of Oceanography at the University of California San Diego. Wright and three co-authors published their analysis in Geophysical Research Letters.

"These findings don't preclude that there could be grains of ice or small balls of ice that are not cementing other minerals together," said Wright. "The question is how likely is ice to be present in that form?"

The second surprise contradicts a leading idea about what happened to the water on Mars. The red planet may have harbored oceans of water early in its history. Many experts suspected that much of the water became part of the minerals that make up underground cement.

"If you put water in contact with rocks, you produce a brand-new set of minerals, like clay, so the water's not a liquid. It's part of the mineral structure," said study co-author Michael Manga of the University of California Berkeley. "There is some cement, but the rocks are not full of cement."

"Water may also go into minerals that do not act as cement. But the uncemented subsurface removes one way to preserve a record of life or biological activity," Wright said. Cements by their very nature hold rocks and sediments together, protecting them from destructive erosion.

The lack of cemented sediments suggests a water scarcity in the 300 meters below InSight's landing site near the equator. The below-freezing average temperature at the Mars equator means that conditions would be cold enough to freeze water if it were there.

Many planetary scientists, including Manga, have long suspected that the Martian subsurface would be full of ice. Their suspicions have melted away. Still, big ice sheets and frozen ground ice remain at the Martian poles.

"As scientists, we're now confronted with the best data, the best observations. And our models predicted that there should still be frozen ground at that latitude with aquifers underneath," said Manga, professor and chair of Earth and planetary science at UC Berkeley.
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www.marsdaily.com

Surprise, surprise: Subsurface water on Mars defy expectations

San Diego CA (SPX) Aug 11, 2022 - A new analysis of seismic data from NASA's Mars InSight mission has revealed a couple of surprises. The first surprise: the top 300 meters of the subsurface beneath the landing site near the M
www.marsdaily.com
 
betel1-640x426.jpg


Astronomers are still making new discoveries about the red supergiant star Betelgeuse, which experienced a mysterious "dimming" a few years ago. That dimming was eventually attributed to a cold spot and a stellar "burp" that shrouded the star in interstellar dust. Now, new observations from the Hubble Space Telescope and other observatories have revealed more about the event that preceded the dimming.

It seems Betelgeuse suffered a massive surface mass ejection (SME) event in 2019, blasting off 400 times as much mass as our Sun does during coronal mass ejections (CMEs). The sheer scale of the event is unprecedented and suggests that CMEs and SMEs are distinctly different types of events, according to a new paper posted to the physics arXiv last week. (It has been accepted for publication in The Astrophysical Journal.)
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arstechnica.com

Betelgeuse is bouncing back after blowing its top in 2019

"We're watching stellar evolution in real time."
arstechnica.com arstechnica.com

Kun kebler data tuli "kansalaistieteilijöille" (citizen scientist) ja pääsi metsästämään exoplaneettoja, kysyin että pystyykö CMEtä näkemään datassa. Vuosien jälkeen on ihan selvää että pystyy. Toinen kysymys on kuiden näkeminen, sitä ei olla vielä vahvistettu.
 
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NASA's 2023 annual Breakthrough, Innovative and Game-Changing (BIG) Idea Challenge asks university students to design a metal production pipeline on the Moon - from extracting metal from lunar minerals to creating structures and tools. The ability to extract metal and build needed infrastructure on the Moon advances the Artemis Program goal of a sustained human presence on the lunar surface.

Its strength and resistance to corrosion make metal key to building structures, pipes, cables and more, but the metal materials for infrastructure are heavy, making them very expensive to transport.

Student teams participating in the BIG Idea Challenge, a university-level competition sponsored by NASA and managed by the National Institute of Aerospace (NIA), will develop innovative ways to extract and convert metals from minerals found on the Moon, such as ilmenite and anorthite, to enable metal manufacturing on the Moon.

The BIG Idea Challenge, now in its eighth year, invites university students to tackle some of the most critical needs facing space exploration and help create the mission capabilities that could make new discoveries possible. The challenge provides undergraduate and graduate students working with faculty advisors the opportunity to design, develop, and demonstrate their technology in a project-based program over the course of a year and a half.

This NASA-funded challenge provides development awards of up to $180,000 to up to eight selected teams to build and demonstrate their concept designs and share the results of their research and testing at the culminating forum in November 2023.

The availability of in-situ resource utilization (ISRU) derived metals on the Moon would allow infrastructure needed for a lunar base - including pipes, power cables, landing pads, transport rails, and pressure vessels to contain volatiles like fuel - to be made locally using additive manufacturing, or 3D printing.

"Here at home, forging metal has long been a key part of building our homes and infrastructure, and the same holds true as we work towards a sustained presence on the Moon," said Niki Werkheiser, director of technology maturation within the agency's Space Technology Mission Directorate (STMD).

"This challenge gives students the opportunity to help develop the future technology that will help us find, process, and manufacture with metal on the lunar surface."

Teams are invited to submit proposals for technologies needed along any point in the lunar metal product pipeline, including, but not limited to:

+ Metal detecting

+ Metal refining

+ Forming materials for additive manufacturing

+ Testing and qualifying 3D printed infrastructure for use on the Moon

+ Drilling, excavation, and transportation of mined materials are excluded from this challenge.

A non-binding notice of intent is due Sept. 30, 2022. Written proposal and video submissions are due on Jan. 24, 2023, in which teams must include a specific, compelling use case that describes how their portion of the metal product production pipeline fits into infrastructure development on the Moon.

Teams should also identify what systems they assume will be in place to support their proposed concept, as well as consider incorporating mechanisms to enable efficient operation on the Moon, including lunar dust mitigation, thermal management, and realistic power considerations.

Teams of at least five and no more than 25 must be composed of students and faculty at U.S.-based colleges and universities affiliated with their state's Space Grant Consortium. Non-Space Grant affiliated colleges and universities may partner with a Space Grant-affiliated institution. Minority Serving Institutions are encouraged to apply. Multi-university and multi-disciplinary teams are encouraged.

"NASA is already thinking about supporting longer-term missions to the Moon. This BIG Idea Challenge theme links university teams to the push toward sustained human presence on the Moon and on other planets," said Tomas Gonzalez-Torres, Space Grant project manager in NASA's Office of STEM Engagement.

"This theme goes beyond initial Artemis missions and starts tackling the mission planning needs once we've returned humans to the Moon. We are excited to see what these teams develop."

The 2022 BIG Idea Challenge is sponsored by NASA through a collaboration between STMD's Game Changing Development program and the Office of STEM Engagement's Space Grant project.
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www.moondaily.com

NASA seeks student ideas for extracting, forging metal on the Moon

Greenbelt MD (SPX) Aug 15, 2022 - NASA's 2023 annual Breakthrough, Innovative and Game-Changing (BIG) Idea Challenge asks university students to design a metal production pipeline on the Moon - from extracting metal from lunar miner
www.moondaily.com
 

"Several of the proposed sites within the regions are located among some of the oldest parts of the Moon, and together with the permanently shadowed regions, provide the opportunity to learn about the history of the Moon through previously unstudied lunar materials," Sarah Noble, Artemis lunar science lead for NASA's Planetary Science Division, added.

The crewed Artemis III mission is not scheduled to launch earlier than 2025, and will carry and man and the first woman to set foot on the lunar surface.
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www.theregister.com

NASA identifies landing sites for next trip to the Moon

Hopefully Lucky 13 spots suggested, all on the south pole near water ice
www.theregister.com www.theregister.com
 
En ollut varma, mihin ketjuun tämän laittaisi joten menkööt tänne:

https://twitter.com/x/status/1562963693490475010

Pari lainausta: LÄHDE

If the Starship program is “delayed longer than expected,” he said the company is considering initially downsizing second-generation satellites — “a sort of Starlink V2 mini” — so they would fit on a Falcon 9.

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“It’s not a substitute for ground cell stations,” Musk said, because those “especially in urban and suburban areas will definitely be superior to what we’re talking about here.

“This is really meant to provide basic coverage to areas that are currently completely dead.”

Redditissä on tästä lisää:

https://www.reddit.com/r/Starlink/comments/wxtrj4/spacex_is_live_with_tmobile_announcement/

Tuossa on SpaceX:n ja T-Mobilen yhteinen julkistusvideo, poimin ketjusta kommentin jossa tiivistetään sen sisältö:

T-Mobile is giving Starlink a small portion of their midband spectrum.

Starlink Sats V2 will have a new antenna that can use that midband spectrum.

2-4Mb/s speeds over like 50sq miles or whatever.

So each person in like, Yellowstone wilderness, gets a few kb for texts. If you're the only one in a 50 or 100 sw mile radius, you could send longer texts or even voice call.

Such that your existing T-Mobile cellphone can send texts, maybe a phone call in ALL the cell tower dead zones of the world (pending partnership with foreign and domestic cell service) T-Mobile states they want to do "reciprocal roaming" where foreign visitors to the US can us their existing phones in the dead zones in T-Mobile/Starlink. And T-Mobile users could use their phones in like , rural Mongolia or whatever.

Basically it's emergency text, calls, possibly SD video once it's out of beta for people adventuring into the wilderness and oceans.

Using your EXISTING phone antenna bands.

Quite remarkable.

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Kuten heidän Starlink internet, tämä ei sovellu kaikkialle: tiheään asutuissa kaupungeissa on parempia ja nopeampia keinoja puheluiden ja internetin välittämiseen. Se missä tämä toimii erinomaisesti ja paljon muita halvemmalla ovat harvaan asutut alueet minne olisi hyvin kallista ulottaa mastojen avulla. Heidän koko bisnesajatus olisi tarjota näitä palveluita (korvausta vastaan tietysti, kapitalisteja tässä ollaan) maailmanlaajuisesti jolloin asiakaskunnan määrä rahoittaisi toiminnan.

Starlink satelliittit pysyvät kiertoradalla viiden vuoden ajan joten uusia pitää ampua lisää kokoajan jotta saadaan korvattua ilmakehään palaavat. Maailmanlaajuinen peitto vaatii suuren määrän satelliitteja, he ovat hakeneet FCC:ltä lupaa yli 30 000 satelliitille. Tällä hetkellä heillä on kiertoradalle ammuttuna yli 2 000 Starlink satelliittia ja lupa laukaista 12 000 satelliittia lisää.

Heidän Starship-raketti on ainoa joka kykenee ampumaan Starlink 2.0 satelliitteja kiertoradalle, ei onnistu nykyisillä Falcon 9 ja Falcon Heavy -raketeilla, tosin kuten Musk kommentoi, jos Starship lipsuu aikataulusta niin on mahdollista että Starlink 2.0 satelliitteja muutetaan siten että on mahdollista ampua niitä Falcon 9 rakteilla. Starship tekee mahdolliseksi ampua 110-120 satelliittia yhdellä laukaisulla, kun nykyisellään ampuvat Falcon 9 raketilla 50-60 satelliittia per laukaisu, tosin nämä satelliitit ovat huomattavasti pienempiä ja kevyempiä verrattuna 2.0. Musk on sanonut että Starlink 2.0 painaa 1 250 kg kun taas nykyiset Starlink-satelliitit painavat 260 kg. Starlink 2.0 ovat reilusti suurempia mittojen puolesta ja olen lukenut että niiden irtoaminen kiertoradalle pitää tehdä eri tavalla, mikä on yksi syy miksei voida laukaista Falcon 9 raketeilla. On myös kirjoitettu että Starlink 2.0 ei mahtuisi mittojen puolesta Falcon 9 kuormatilaan, mutta en ole varma kuinka luotettava "tieto" on kyseessä ja vaikka pitäisikin paikkansa, onko tuo asia joka voidaan korjata "pienellä muutoksella" satelliitteihin.

Joka tapauksessa jo pelkästään painon takia Starlink 2.0 laukaisut Falcon 9 raketeilla ei olisi niin kustannustehokasta kuin mitä Starship-raketeilla - toki Starship pitää ensin saada toimimaan ja sen jälkeen lentämään tiuhaan. Sen ensilento ehkä tänä vuonna, tosin voi myös lipsahtaa ensi vuoden puolelle. Tiheään lentäminen vaatii tietyt luvat ja niiden käsittely on kesken.

SpaceX:n koko toiminnan ydinajatus on tämä maailmanlaajuinen internet ja puhelinpalvelu Starlink-satelliittien kautta: siitä halutaan hyvin lypsävä lehmä joka puolestaan rahoittaa kaiken muun toiminnan - erityisesti Mars-lennot. He eivät tietysti tee hyväntekeväisyyttä vaan ampuvat raketeilla muidenkin satelliitteja sekä osallistuvat NASA:n ja muiden tarjouskilpailuihin. Nämä ovat kuitenkin lopulta pienehköjä rahavirtoja jos vertaa siihen, että saisi tietyn palasen koko maailman internet-markkinoista: se on helposti kymmeniä miljardeja per vuosi ja rahavirta olisi tasainen. Heillä on omissa käsissä rakettien kehitys, laukaisu sekä satelliitit joten eivät ole riippuvaisia ulkopuolisista tekijöistä. Hyvin kallista lystiä siis, kehitystyöhön on palanut kymmeniä miljardeja viimeisen 10 vuoden aikana mutta onnistuessaan palkinto olisi huomattava.
 
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“There are certain fundamental aspects of deep space exploration that are really independent of money,” says Jim Geffre, Orion Vehicle Integration Manager at the Johnson Space Center in Houston. “The laws of physics haven’t changed since the 1960s. And capsule shapes happen to be really good for coming back into the atmosphere at Mach 32.”

Roger Launius, who served as NASA’s chief historian from 1990 to 2002 and as a curator at the Smithsonian Institution from then until 2017, tells of a conversation he had with John Casani, a veteran NASA engineer who managed the Voyager, Galileo and Cassini probes to the outer planets.

“I have a name for missions that use too much new technology,” he recalls Casani saying. “Failures.”

The Artemis I flight is slated for about six weeks. (Apollo 11 lasted eight days.) The ship roughly follows Apollo’s path to the moon’s vicinity, but then puts itself in what NASA calls a distant retrograde orbit. It swoops within 110 km of the lunar surface for a gravity assist, then heads 64,000 km out—taking more than a month but using less fuel than it would in closer orbits. Finally, it comes home, reentering the Earth’s atmosphere at 11 km per second, slowing itself with a heatshield and parachutes, and splashing down in the Pacific not far from San Diego.
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spectrum.ieee.org

NASA’s Artemis I Revives the Moonshot

On Artemis I, the first test flight, mission managers say they are taking the SLS, with its uncrewed Orion spacecraft up top, and “stressing it beyond what it is designed for”—the better to ensure safe flights when astronauts make their first landings, currently slated for Artemis III in 2025.
spectrum.ieee.org spectrum.ieee.org
“That extra time in space,” says Geffre, “allows us to operate the systems, give more time in deep space, and all those things that stress it, like radiation and micrometeoroids, thermal environments.”

There are, of course, newer technologies on board. Orion is controlled by two vehicle management computers, each comprised of two flight computer modules (FCMs) to handle guidance, navigation, propulsion, communications and other systems. The flight control system, Geffre points out, is quad-redundant; if at any point one of the four FCMs disagrees with the others, it will take itself offline and, in a 22-second process, reset itself to make sure its outputs are consistent with the others’. If all four FCMs fail, there is a fifth, entirely separate computer running different code to get the spacecraft home.

Guidance and navigation, too, have advanced since the sextant used on Apollo. Orion uses a star tracker to determine its attitude, imaging stars and comparing them to an onboard database. And an optical navigation camera shoots the Earth and moon so that guidance software can determine their distance and position and keep the spacecraft on course. NASA says it’s there as backup, able to get Orion to a safe splashdown even if all communication with Earth has been lost.

But even those systems aren’t entirely new. Geffre points out that the guidance system’s architecture is derived from the Boeing 787. Computing power in deep space is limited by cosmic radiation, which can corrupt the output of microprocessors beyond the protection of Earth’s atmosphere and magnetic field.
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Beginning in April of this year, NASA conducted four separate "wet dress rehearsal" tests during which the agency aimed to fully fuel the SLS rocket and countdown to T-10 seconds, ending the test before ignition of the main engines. Each of these four tests ultimately ended prematurely, although the fourth attempt in June saw engineers bring the rocket down to T-29 seconds.

However, to reach that late stage in the countdown, NASA had to "fool" the flight computer. During the test, a 4-inch hydrogen line—smaller than the problematic 8-inch line on Monday—had a leaky seal. To complete the wet dress test, NASA chose to mask the leak from the ground launch sequencer, the ground-side computer that controls the majority of the countdown.

Because of this masking, NASA could not complete the engine chill portion of the test. Had it done so, the agency may well have uncovered the problem that caused a scrub on Monday. In hindsight, therefore, NASA probably should have completed a full wet dress rehearsal before rolling the rocket out for a launch. Instead, the agency effectively attempted a fifth wet dress test on Monday, when the world was expecting a launch.

NASA's chief of human exploration systems development, Jim Free, defended the decision to attempt a launch on Monday without completing a wet dress test. "We felt, and still feel, like going for today was the right thing to do," Free said of the launch attempt.

Free said NASA is conscious of the wear-and-tear involved in rolling the SLS rocket to and from the launch pad for additional wet-dress tests and in pressurizing the tanks during fueling. Those risks must be balanced against challenges during the countdown.

Now, NASA may be rolling the rocket back to the Vehicle Assembly Building at Kennedy Space Center anyway. Agency officials said they were leaving open the possibility of a launch attempt at 12:48 pm ET on Friday, September 2. After a meeting on Tuesday afternoon to discuss possible fixes to the engine bleed issue, mission managers will announce a plan forward.

If the rocket cannot launch by September 5, it will need to go back to the hangar for additional work. Then, it's likely that the rocket would not launch before mid-October.
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arstechnica.com

Warning sign? NASA never finished a fueling test before today’s SLS launch attempt

"I am very proud of this launch team."
arstechnica.com arstechnica.com
 
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