The Search for Extraterrestrial Life 17Interest in moon exploration and bases is growing and it turns out there is more water there (carried by the solar wind) than thought
In our universe:
We’re always learning new things now. The universe “has 2−3× more light than expected from the integrated light from galaxies” “According to new measurements by New Horizons, the light coming from stars beyond the Milky Way is two to three times brighter than the light from known populations of galaxies – meaning that there are even more out there than we thought! – Matt Williams, Universe Today, (December 24, 2022) The paper is open access.
While we’re here, rogue stars may be even older than we thought: “”We don’t exactly know what made them homeless. Current theories cannot explain our results, but somehow they were produced in large quantities in the early universe,” James Jee, an astronomer at Yonsei University in South Korea and co-author on the new research, said in a statement. “In their early formative years, galaxies might have been pretty small and they bled stars pretty easily because of a weaker gravitational grasp.”” – Stephanie Walden, Space.com, (January 5, 2022)
Here’s what the Sci Show tells us to expect from space exploration in 2023:
In our galaxy:
At Medium, physics writer Richard Vincent offered last year, “Who is to say the Earth is typical? Or that life tends to appear on planets like Earth? Maybe we are a cosmic accident in an otherwise desolate and lifeless universe? The problem is, it’s not a good idea to imagine we’re special. Cosmology — the study of the universe itself — is specifically built on us not taking a privileged vantage point. For us to apply our laws of physics to the whole of reality, we rely on the fact that whatever happens here applies, broadly speaking, everywhere else too.” – “Are we wrong about aliens?” (February 19, 2022)
This sounds confused. First, Earth is not typical. It is a rare type of planet. So we are special. But there is a difference between being special and being unique. There is a very large number of planets out there and some, though not most, may be special too.
Our Milky Way — to take another, much larger example — is thought to be similar only to some other galaxies. “There’s still much to learn, but this study offers a lot of new possibilities to chew on when it comes to galactic evolution. Fundamentally, it shows that we are not entirely unique. There is an enormous variety of galaxy types in the Universe, but at least some of them play by the same rules as the Milky Way, and many are at the same life stage.” – Scott Alan Johnston, Universe Today (December 23, 2022) The paper is open access.
While we are here, cosmology — like all sciences — is based on evidence, not on opinions about vantage points. All that out of the way…
Astrophysicist David Kipping, in a lecture at Columbia University (November 18, 2022), argues that we might be alone in the universe:
He summarized his argument on Twitter, based on his 2020 open access paper: “Our late arrival gentle nudges us towards the view that we may be rare. The rare-intelligence scenario is favored over a marginalized ensemble at 3:2 odds. But 3:2 isn’t far off 50:50! So really it remains v uncertain & by no means discourages SETI!”
Stony Brook astrophysicist Paul Sutter, meanwhile, offers a rather different take on why we don’t encounter intelligent aliens. Assume there are other intelligent beings in the universe: “If the aliens were to receive a signal, they would spring into action, crafting a message of their own or even a probe to visit their new friends. But all this takes time. A lot of it. We’ve been broadcasting for less than a century, meaning our “radio bubble” is less than 200 light-years wide, compared with the 100,000-light-year width of the entire Milky Way. So it may take hundreds or thousands of years for our signals to reach an alien civilization. If they respond with a signal of their own, we could get it in another few thousand years — that is, if we see it at all, because we would have to be looking in the right direction at the right time to capture it. If the aliens decide to send a probe, it will have to crawl along the interstellar depths at a fraction of the speed of light, so it will take even longer to get here.” – Space.com (December 20, 2022)
Meantime, we look for exoplanets that might feature life.
What’s happening with exoplanets today:
Space.com’s picks for the nine biggest alien planet discoveries of 2022 here. Includes: “In September, astronomers announced that a new type of exoplanet had been discovered. Made of about half-rock and half-water, either in liquid or ice form, the exoplanets were found orbiting the most common stars in the universe. The finding may have great consequences in the search for life in the cosmos, researchers say. Red dwarfs are the most common type of star, making up more than 70% of the universe’s stellar population. Astrophysicists examined small worlds found around closer — and thus brighter and easier to inspect — red dwarfs observed by NASA’s Transiting Exoplanet Survey Satellite (TESS).” – Charles Q. Choi, 9 alien planet discoveries that were out-of-this-world in 2022 (December 30, 2022)
More: “New class of exoplanet! Half-rock, half-water worlds could be abodes for life” (September 8, 2022)
In our solar system:
A large volcanic outburst was recently spotted on Jupiter’s moon Io: “Io is the innermost of Jupiter’s four large moons and is the most volcanic body in the Solar System thanks to the tidal stresses it feels from Jupiter and two of its other large satellites, Europa and Ganymede. ” – Planetary Science Institute, Phys.org, (January 3, 2023)
Could we have space colonies on asteroids? “The metal-rich asteroid 16 Psyche is a good possibility. Mining the interior of its estimated trillions of dollars worth of rare earth metals would also provide a radiation-shielded habitat, as long as rapidly spinning Psyche doesn’t cause it to fly apart. On this point, the concept looks promising. One study of spinning asteroids found that solid ones up to a few hundred yards in diameter should tolerate a spin rate fast enough to sustain artificial gravity up to half a gee or so.” – Brian Koberlein and Universe Today, MSN (December 15, 2022) The idea is not yet considered practical.
Here’s what such a colony might look like:
More re metal-rich 16 Psyche:
Right in our neighborhood
Winter on Mars: “Thanks to these dedicated orbiters, landers, and rovers, scientists have learned a few salient facts about snow on Mars: it comes in two varieties (water ice and dry ice), and it only ever snows in the coldest regions and times – at the poles, under cloud cover, and at night. Because Mars’ atmosphere is so thin and its temperatures so extreme, water and carbon dioxide do not freeze but sublimate, transforming from a gas directly to ice (and back again). On top of that, dry ice snowflakes are cubic, meaning they have four sides instead of the familiar six-sided configuration we are familiar with.” – Matt Williams, Universe Today, (January 3, 2023)
Water on the surface of the moon:
First clearly discovered in 2008, water on the moon is carried on the solar wind. “The amount of water on the lunar surface varies widely both based on the time of the lunar day and the latitude it is located at. There is so much variability that the water content of the lunar soil can be 200 ppm higher or lower at different times of the day. ” – Andy Tomaswick, Universe Today (December 29, 2022)
“We thought that the water on the sunlit part of the Moon would have evaporated – but we found it! Now we will delve deeper into how this water is created and how it persists.” – Molly Wasser, “There’s Water on the Moon?”, NASA, (November 5, 2020)
The possibility of capturing water affects where moon bases might be placed.
Here at home
Earth as seen from the Moon by Danuri, South Korea’s low lunar orbit mission:
Everybody is going to the Moon now. The new destination for the truly adventurous will likely be Venus, if not Mars. 😉
Another way the universe is fine-tuned for life
Steve Meyer notes,
Physicists have determined that if the matter at the beginning of the universe had been configured even slightly differently, there would be either an extreme clumping of matter resulting in a universe in which only black holes would exist or, alternately, a highly diffuse arrangement of matter without any large-scale structures at all. Both of these alternatives would have prevented the formation of stable galaxies and stars in which life-friendly solar systems might later emerge. –Stephen C. Meyer. The Return of the God Hypothesis, HarperCollins. Kindle Edition, 2021, p. 228, Kindle edition).
You may also wish to read: The search for extraterrestrial life 16. The Webb wraps up a year of solid achievements, including the first direct image of an exoplanet. So far, our solar system seems to be unusual but it’s too early to be sure because systems with other types of planets may be easier to spot.