Space Stories: Old Stars Harboring Exoplanets, a Hot “Earth” Located, and the Role of Exomoons

Posted on by onespaceman2000
Image (Credit): Artist’s rendering of an Earth-like exomoon orbiting a gas giant planet in a star’s habitable zone. (NASA/JPL-Caltech)

Here are some recent stories of interest related to exoplanets.

—Phys.org: “Old Stars May Be the Best Places to Search for Life“

Once upon a cosmic time, scientists assumed that stars apply an eternal magnetic brake, causing an endless slowdown of their rotation. With new observations and sophisticated methods, they have now peeked into a star’s magnetic secrets and found that they are not what they expected. The cosmic hotspots for finding alien neighbors might be around stars hitting their midlife crisis and beyond. This groundbreaking study, shedding light on magnetic phenomena and habitable environments, has been published in The Astrophysical Journal Letters.

—NASA: “Earth-sized Planet Has a ‘Lava Hemisphere’“

In a system with two known planets, astronomers spotted something new: a small object transiting across the Sun-sized star. This turned out to be another planet: extra hot and Earth-sized…The newly-spotted planet, called HD 63433 d, is tidally locked, meaning there is a dayside which always faces its star and a side that is constantly in darkness. This exoplanet, or planet outside of our solar system, orbits around the star HD 63433 (TOI 1726) in the HD 63433 planetary system. This scorching world is the smallest confirmed exoplanet younger than 500 million years old. It’s also the closest discovered Earth-sized planet this young, at about 400 million years old.

—UniverseToday: “Big Planets Don’t Necessarily Mean Big Moons’”

Does the size of an exomoon help determine if life could form on an exoplanet it’s orbiting? This is something a February 2022 study published in Nature Communications hopes to address as a team of researchers investigated the potential for large exomoons to form around large exoplanets (Earth-sized and larger) like how our Moon was formed around the Earth. Despite this study being published almost two years ago, its findings still hold strong regarding the search for exomoons, as astronomers have yet to confirm the existence of any exomoons anywhere in the cosmos. But why is it so important to better understand the potential for large exomoons orbiting large exoplanets?

Space Stories: Tom Hanks Returns to the Moon, Exomoons are Questioned, and Our Moon Enters a New Phase

Posted on by onespaceman2000
Image (Credit): Tom Hanks at the opening of his new show in London. (Apollo Remastered)

Here are some recent stories of interest.

—Reuters: “Tom Hanks Brings Love of Space to New Immersive London Show“

Archive footage of space rockets taking off beam across giant walls in a new immersive show in London, as Hollywood actor Tom Hanks narrates the story of human voyages to the moon. “The Moonwalkers: A Journey With Tom Hanks” looks at the first moon landings of the Apollo missions from 1969 to 1972 and their successor, NASA’s human spaceflight program, Artemis. The next mission – the Artemis II lunar flyby – is planned for next year and interviews with the four-member team are also projected on the walls at the Lightroom gallery space in London’s King Cross area.

—Max Planck Institute for Solar System Research: “Giant Doubts About Giant Exomoons“

Just as it can be assumed that the stars in our Milky Way are orbited by planets, moons around these exoplanets should not be uncommon. This makes it all the more difficult to detect them. So far, only two of the more than 5300 known exoplanets have been found to have moons. A new data analysis now demonstrates that scientific statements are rarely black or white, that behind every result there is a greater or lesser degree of uncertainty and that the path to a statement often resembles a thriller. In observations of the planets Kepler-1625b and Kepler-1708b from the Kepler and Hubble space telescopes, researchers had discovered traces of such moons for the first time. A new study now raises doubts about these previous claims. As scientists from the Max Planck Institute for Solar System Research and the Sonnenberg Observatory, both in Germany, report in the journal Nature Astronomy, “planet-only” interpretations of the observations are more conclusive.

—The University of Kansas: “Scholars Say it’s Time to Declare a New Epoch on the Moon, The ‘Lunar Anthropocene’“

Human beings first disturbed moon dust Sept. 13, 1959, when the USSR’s unmanned spacecraft Luna 2 alighted on the lunar surface. In the following decades, more than a hundred other spacecraft have touched the moon — both crewed and uncrewed, sometimes landing and sometimes crashing. The most famous of these were NASA’s Apollo Lunar Modules, which transported humans to the moon’s surface to the astonishment of humankind. In the coming years, missions and projects already planned will change the face of the moon in more extreme ways. Now, according to anthropologists and geologists at the University of Kansas, it’s time to acknowledge humans have become the dominant force shaping the moon’s environment by declaring a new geological epoch for the moon: the Lunar Anthropocene.

Video: More on the Importance of Exomoons

Posted on by onespaceman2000
Image (Credit): Artist’s rendering of an exomoon. (Cool Worlds Lab)

If you watched my earlier post on Cool Worlds Lab’s missed opportunity on an exomoon proposal with the James Webb Space Telescope, then you will enjoy this updated video where Assistant Professor of Astronomy David Kipping provides five reasons that the study of exomoons is so important.

I do not want to give too much away, but one of the reasons is that the search for life on exoplanets needs to consider not only the chemical composition of the exoplanet, but the orbiting exmoon as well. If we assume everything we are seeing in the light from the observed exoplanet comes from only the exoplanet, we may experience a number of false positives because the life-affirming chemicals may not be combined in one object but instead come from two dead objects that only appear as one.

This makes sense, but it also throws a wrench into things. If we are struggling to build telescopes large enough to truly understand an exoplanet’s composition, we are now much farther away from a useful telescope because of the impact of exomoons. Of course, this is not the fault of the exomoons, but rather a reality that must be added to the equation.

Check out the video as Dr. Kipping makes his argument. It is pretty convincing.

In Case You Missed It/Video: Missed Opportunity on Exomoons

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Image (Credit): Assistant Professor of Astronomy David Kipping sharing his story of rejection. By the way, the image behind him is the exomoon Pandora from the movie Avatar. (Cool Worlds Lab)

A few months back, Assistant Professor of Astronomy David Kipping shared a short video regarding his organization’s failure to secure James Webb Space Telescope (JWST) time to search for exomoons that he knows are there. His organization, Cool Worlds Lab, has done some amazing work studying and publicizing issues related to astronomy. You should visit his site for some challenging topics.

What is unique about his video is that it was recorded only one hour after he learned that his organization would not be able to use JWST for his exomoon search and he wanted to share what rejection felt like “in real time.” He goes on to say that such rejection is part of science, as brutal as it may feel at the moment, noting that for every seven JWST proposals, only one will be approved.

Fortunately, we have scientists out there with very thick skin sharing new ideas and proposals. And Dr. Kipping will not be giving up on his exomoon push anytime soon. That is good news for all of us.

Are We Too Focused on the Goldilocks Zone?

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Image (Credit): Saturn’s moon Enceladus. (NASA)

Astronomers peering into the night sky always talk about exoplanets located in the “Goldilocks Zone,” or “Habitable Zone,” similar to the Earth’s location from the sun. But what if that is too limited? What if we should also be focusing on colder regions as well as exomoons?

The new study released this week based on data from NASA’s spacecraft Cassini has found that Saturn’s moon Enceladus contains the ingredients for life as we know it. The study states:

Saturn’s moon Enceladus harbours a global ice-covered water ocean. The Cassini spacecraft investigated the composition of the ocean by analysis of material ejected into space by the moon’s cryovolcanic plume. The analysis of salt-rich ice grains by Cassini’s Cosmic Dust Analyzer enabled inference of major solutes in the ocean water (Na+, K+, Cl–, HCO3–, CO32–) and its alkaline pH. Phosphorus, the least abundant of the bio-essential elements, has not yet been detected in an ocean beyond Earth. Earlier geochemical modelling studies suggest that phosphate might be scarce in the ocean of Enceladus and other icy ocean worlds. However, more recent modelling of mineral solubilities in Enceladus’s ocean indicates that phosphate could be relatively abundant.

Again, this represents the building blocks of life and it is the first time all these ingredients have been discovered in our solar system outside of Earth. We did not find it on Venus or Mars, two other planets in the Goldilocks Zone. No, it was found in a much colder part of the solar system on a tiny moon.

This discovery certainly mixes up the situation and provides a much broader region for life to appear in other solar systems. It’s not a new idea, but it has more credibility now that we know a little more about our own neighborhood.

Maybe Goldilock’s concerns about something being too cold was not such a problem after all.

Note: It seems James Cameron figured this out years ago. The planet visited in the Avatar movies, Pandora, is portrayed as a moon (or exomoon) in the Alpha Centauri System.

Image (Credit): Pandora and its host  gas giant Polyphemus from the movie Avatar. (20th Century Fox)