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Lava Tubes on the Moon Maintain Comfortable Room Temperatures Inside – Universe Today



Searching for a comfortable place to set up a research station on the Moon? Look no further than the interior parts of lunar pits and caves. While lack of air will be an issue, new research indicates these underground sanctuaries have steady temperatures that hover around 17 Celsius, or 63 Fahrenheit, even though the Moon’s surface heats up to about 127 C (260 F) during the day and cool to minus 173 C (minus 280 F) at night.

Lunar pits, or lava tubes were discovered in 2009 by the Lunar Reconnaissance Obiter and Japan’s Kaguya spacecraft. These are deep holes on the moon that could open into vast underground tunnels. They likely could serve as a safe shielding from cosmic rays, solar radiation and micrometeorites for future human lunar explorers. But now we know they could provide thermally stable sites for lunar exploration.

These long, winding lava tubes are like structures we have on Earth. They are created when the top of a stream of molten rock solidifies and the lava inside drains away, leaving a hollow tube of rock. For years before their existence was confirmed, scientists thought there were hints that the Moon had lava tubes based on observations of long, winding depressions carved into the lunar surface by the flow of lava, called sinuous rilles.

Thurston Lava Tube on the Big Island of Hawaii. Credit: P. Mouginis-Mark, LPI

So far, about 200 lunar pits have been found and at least 16 of these are probably collapsed lava tubes, with the potential for ‘livable’ space, said Tyler Horvath, a UCLA doctoral student in planetary science, who led the new research. Two of the most prominent pits have visible overhangs that clearly lead to some sort of cave or void, and there is strong evidence that another’s overhang may also lead to a large cave.

Horvath processed images from the Diviner Lunar Radiometer Experiment — a thermal camera and one of six instruments on LRO — to find out if the temperature within the pits diverged from those on the surface. Diviner is designed to measure surface temperatures on the Moon, and Horvath’s team had to focus in on extremely small areas to get their data.

They focused on a pit found in the Sea of Tranquility (Mare Tranquillitatis). This image, below, was taken as the Sun was almost straight overhead, illuminating the region. By comparing this image with previous images that have different lighting, scientists can estimate the depth of the pit. They believe it to be over 100 meters.

This is a spectacular high-Sun view of the Mare Tranquillitatis pit crater, revealing the overhang and deep, dark pit. This image from LRO’s Narrow Angle Camera is 400 meters (1,312 feet) wide, north is up.
Credits: NASA/Goddard/Arizona State University

The researchers used computer modeling to analyze the thermal properties of the rock and lunar dust and to chart the pit’s temperatures over a period of time. Their research, recently published in the journal Geophysical Research Letters, revealed that temperatures within the permanently shadowed reaches of the pit fluctuate only slightly throughout the lunar day, remaining at around 17 C (63 F). If a cave extends from the bottom of the pit, as images taken by the Lunar Reconnaissance Orbiter Camera suggest, it too would have this relatively comfortable temperature. The researchers think the overhang is responsible for the steady temperature, limiting how hot things get during the day and preventing heat from radiating away at night.

However, if this particular pit was to be used as a habitat or research station, there would likely be a heat problem just inside the pit. The sunbaked part of the pit floor not protected by the overhang hits daytime temperatures close to 150 C (300 F), which is even hotter than the Moon’s surface.

“Because the Tranquillitatis pit is the closest to the lunar equator, the illuminated floor at noon is probably the hottest place on the entire moon,” said Horvath.

Two views of another lunar pit in Mare Ingenii. Credit: NASA/GSFC/Arizona State University.

Since a day on the Moon lasts nearly 15 Earth days, the lunar surface is constantly bombarded by sunlight and is frequently hot enough to boil water. Conversely, the equally long lunar nights (also 15 Earth days long) reach incredibly cold temperatures. Any habitat or base would mean inventing heating and cooling equipment that can operate under these conditions, as well as ways to produce enough energy to power it nonstop. This could prove to be an insurmountable barrier to lunar exploration or habitation.

However, the researchers say that building bases in the shadowed parts of these pits allows scientists to focus on other challenges, like growing food, providing oxygen for astronauts, gathering resources for experiments and expanding the base.

“Humans evolved living in caves, and to caves we might return when we live on the moon,” said UCLA professor of planetary science David Paige, who leads the Diviner Lunar Radiometer Experiment and participated in the research.

Further reading: Press releases from UCLA and NASA, and the team’s research paper

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NASA releases new 'Penguin and Egg' image from James Webb Space Telescope –



NASA has released a stunning new image from the James Webb Space Telescope (JWST) marking the two-year anniversary of the release of its first images. And the space agency is calling it the “Penguin and Egg.”

What exactly are we looking at? Well, it’s two interacting galaxies known jointly as Arp 142 that lie 326 million light-years from Earth.

They are 100,000 light-years apart, which may sound far, but in astronomical terms, that’s very close. In contrast, our Milky Way and the closest major galaxy to us — the Andromeda galaxy — are separated by 2.5 million light years.

The Penguin and Egg galaxies made their first pass some time between 25 and 75 million years ago, NASA said in a release. This, in turned, triggered a new star formation in the Penguin.

Galactic mergers can cause galaxies to form thousands of new stars a year over millions of years. In the case of the Penguin, NASA said, research suggests that about 100 to 200 new stars have formed each year. This is many times more than what is happening in our own galaxy, where only roughly six to seven new stars form each year.

Webb’s mid-infrared view of interacting galaxies Arp 142. This image was taken by MIRI, the telescope’s mid-infrared instrument, which astronomers use to study cooler and older objects, dust, and extremely distant galaxies. (NASA, ESA, CSA, STScI)

Before the galactic interaction, the Penguin was a spiral galaxy. Now, the centre forms the “eye” of the Penguin. The Egg, on the other hand, is an elliptical galaxy, which contains much older stars. 

At the top right of the image is the PGC 1237172 galaxy, which is 100 million light-years closer to Earth, according to a release by the Space Telescope Science Institute in Baltimore, Md.

And, of course, in the background lie thousands more galaxies.

The gift that keeps on giving

JWST is the successor to the Hubble Space Telescope.

Unlike Hubble’s one mirror, JWST has 18 individual mirrors that make up for one giant one. That makes it a light-catching machine, allowing it see some of the faintest objects and to peer far back into the earliest times of the universe. 

That’s why astronomers were so excited when this game-changing telescope was launched on Dec. 25, 2021. It was a Christmas gift headed to orbit around the moon, just waiting to be unwrapped.

The first image released blew astronomers away.

The blackness of space is dotted with bright stars and galaxies.
The first image released by the James Webb Space Telescope shows thousands of galaxies. (NASA)

It was the telescopes’s first wide-field image, which provided the sharpest and deepest infrared image of thousands of galaxies.

And JWST is the gift that keeps on giving, particularly to astronomers looking to better understand our universe and how we got here.

The telescope, with its massive light-collecting capability, is changing the way astronomers look at our universe. Its observations have challenged the idea of how stars form and even how fast the universe is expanding.

The view from inside the Milky Way galaxy looks crowded with so many stars on a black background in a colourful spectrum, from cyan to magenta.
This image from the James Webb Space Telescope reveals a 50 light-years-wide portion of the Milky Way’s dense centre. An estimated 500,000 stars shine in this image of the Sagittarius C (Sgr C) region, along with some as-yet unidentified features. (Samuel Crowe/UVA/STScI/NASA/ESA/CSA/NASA/ESA/CSA)

“[I’m] incredibly, incredibly grateful because the pictures that we are able to see now … it was not something that we thought we will be able to see,” said Lamiya Mowla an assistant professor at Wellesley University in Wellesley, Mass.

She is one of several scientists who are part of the Canadian NIRISS Unbiased Cluster Survey (CANUCS).

“[Previously,] we were talking about that we will be able to resolve things down to … hundreds of light years or so, down to that level in a very, very early universe. Now, we can see that we can almost get down to tens of light years.”

Data on exoplanets a ‘game changer’

And while we don’t get the jaw-dropping images from Webb when it comes to the study of exoplanets — planets orbiting other stars — its data is proving to be incredibly helpful in understanding planetary atmospheres, especially larger planets that are more similar to our outer planets, such as Jupiter and Neptune.

“If you look at other planets like hot Jupiters, or even colder, like Neptune, or Neptune-sized planets that are a bit colder … James Webb is really a game changer,” said Olivia Lim, a PhD student at the Université de Montréal and member of the Trottier Institute for Research of Exoplanets, who’s main area of focus is the seven-exoplanet system known as TRAPPIST-1

“People are able to measure things that we weren’t able to measure before or they’re they’re able to do it with so much more precision.”

And, of course, the telescope has also provided images of phenomena closer to home, such as a jaw-dropping image of Uranus and its rings.

A ringed planet hangs in the blackness of space with stars and galaxies scattered around it.
This image of Uranus from NIRCam (near-infrared camera) on NASA’s James Webb Space Telescope shows the planet and its rings in new clarity. (NASA, ESA, CSA, STScI)

Mowla said that she’s incredibly grateful for JWST and what it can tell us about our own origins.

“The things that we are seeing over here is what it has taken the universe to get us to the point that we are at today, the world that we take for granted. It has spent 13.7 billion years to build this perfect Earth,” she said.

“I’m pretty sure there are habitable planets in every galaxy. We just haven’t found them yet.”

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NASA Hopeful Boeing Starliner Can Return Astronauts to Earth



With NASA astronauts docked at the International Space Station far longer than planned, the agency’s leadership on Wednesday acknowledged potential alternatives to Boeing’s (NYSE:BA) Starliner for returning the crew to Earth.

Still, the Boeing’s spacecraft remains the primary option for returning crew, officials said.

Officials say Starliner capsule “Calypso” may return as soon as the end of this month from its extended ISS stay, pending results of testing a faulty propulsion system. Starliner has now been in space 36 days and counting as the agency and Boeing perform additional testing in New Mexico before clearing the spacecraft to return.

The mission is the first time Starliner is carrying people, flying NASA astronauts Butch Wilmore and Suni Williams.

NASA’s Commercial Crew manager Steve Stich emphasized during a press conference that the first “option today is to return Butch and Suni on Starliner,” adding, “we don’t see any reason” currently to turn to the agency’s other transportation option, which would be SpaceX’s Crew Dragon, to bring back the astronauts.

Stich — while acknowledging that a SpaceX capsule could be part of contingency plans in case Starliner were to return from the ISS empty — noted that NASA does not yet need to “make a decision as to whether we need to do anything different.”

BA, for its part, saw its stock gain 69 cents first thing Thursday to $184.42.



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Milky Way galaxy can be larger than expected: study



This photo taken on Sept. 13, 2023 shows the Milky Way at the Altun Mountains National Nature Reserve in northwest China’s Xinjiang Uygur Autonomous Region. (Xinhua/Hao Zhao)

KUNMING, July 12 (Xinhua) — The Milky Way galaxy can be larger than previously expected and have a more complex radial structure, according to scientists.

The study, conducted by researchers from Yunnan University and several international institutes, was recently published in Nature Astronomy.

Using data from stellar spectroscopic surveys, researchers constructed a radial density distribution of stars from the inner to the outer regions of the Galaxy, measuring the Galaxy’s radius.

The result indicates that the Galactic disk structure in the outer disk region conforms to a classical exponential distribution while the inner disk region remains nearly flat. This finding is distinct from the long-standing assumption of a single exponential disk for the Galaxy, according to Lian Jianhui, a researcher at Yunnan University.

Lian said the study can impact measuring the Galaxy’s key physical properties. Based on the assumption in the past, the half-light radius of the Galaxy, within which half of its luminosity is contained, was estimated to be about 10,000 light-years. The radius was extraordinarily smaller compared to galaxies of similar mass, and thus, the Galaxy was classified as a compact galaxy.

However, based on the complex density distribution proposed in the study, the Galaxy’s half-light radius is 19,000 light-years, almost in line with the radius of nearby galaxies of similar mass. This indicates that the Galaxy is a typical disk galaxy in terms of size, said Lian.

Lian said the study contributes to understanding the Galaxy’s overall structure and evolution.  ■



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