Astronomers spot 2 intriguing alien worlds around ultracool star

[Admin]

Astronomers have discovered two super-Earths orbiting an ultracool dwarf star 100 light-years away, and one of the planets could support the existence of liquid water, a vital ingredient of life.

Astronomers spot 2 intriguing alien worlds around ultracool star : Read more

 

[rod]

These must be very new, do not see yet at the confirmed exoplanet sites.

The Extrasolar Planets Encyclopaedia (exoplanet.eu), and NASA Exoplanet Archive (caltech.edu)

When searching these two sites, I find some 60 to 90% of all exoplanets listed fall within 3 au or less from the parent stars and many of these planets show much more mass than seen in our solar system from the Sun out to the main belt asteroids. Very different exoplanet configurations out there. Water by the way, as flowing water disrupts abiogenesis experiments here on Earth and so do asteroid impacts

 

[rod]

Okay, the exoplanet.eu site is now updated with these two new planets. They are confirmed and listed at 13 and 25 earth masses The Extrasolar Planet Encyclopaedia — LP 890-9 b (exoplanet.eu) and The Extrasolar Planet Encyclopaedia — LP 890-9 c (exoplanet.eu)

Note the article lead here, "Astronomers have discovered two super-Earths orbiting an ultracool dwarf star 100 light-years away, and one of the planets could support the existence of liquid water, a vital ingredient of life." and "The newly discovered planets orbit an ultracool dwarf star and one is in the habitable zone, making it a prime target for further investigation."

 

[rod]

Here is some more I found on the potential habitable zone and these two exoplanets reported.

Potentially habitable "super-Earth" discovered 100 light-years away, Potentially habitable "super-Earth" discovered 100 light-years away (msn.com)

From this report, "An international team of scientists announced on Wednesday that they have discovered two new "super-Earth" planets just 100 light-years away. Both of them are significantly larger than our own planet — and one of them may even be suitable for life... But it's a second planet previously unknown to scientists that has proven to be the most intriguing. LP 890-9c, or SPECULOOS-2c, lies slightly farther away from its star than the first planet. It's about 40% bigger than Earth with a radius of more than 5,400 miles and takes about three times as long as its neighboring planet to orbit its star... According to researchers, that orbit duration is within the star's habitable zone. "Although this planet orbits very close to its star, at a distance about 10 times shorter than that of Mercury around our sun, the amount of stellar irradiation it receives is still low, and could allow the presence of liquid water on the planet's surface, provided it has a sufficient atmosphere," study co-author Francisco Pozuelos said. That's because the planet's star, LP 890-9, is about 6.5 times smaller and is roughly half as cool temperature-wise as our sun, he explained. "This explains why LP 890-9c, despite being much closer to its star than the Earth is to the Sun, could still have conditions that are suitable for life," Pozuelos added. Researchers now plan to study the atmosphere of the planet to determine just how habitable it could be. Based on their findings, it's believed that it could be the second most favorable terrestrial planet to sustain life."

The exoplanet.eu site is updated with these two new exoplanets as my post #3 shows. They are listed at 13 and 25 earth masses which is near the Uranus and larger than Neptune mass in our solar system. Looks like plenty of hype concerning habitable zone, water, and life when reporting on such large exoplanets if the properties are accurate. Given the mass and radius shown for LP 890-9 c, mean density ~ 54.431 g cm^-3.

5.4431E+01​

 

[rod]

Here is some more on the exoplanets. Hot Earth or Young Venus? A nearby transiting rocky planet mystery, [2209.03105] Hot Earth or Young Venus? A nearby transiting rocky planet mystery (arxiv.org)

From the paper, "Although the masses of the two planets remain to be measured, the discovery team estimated that LP 890-9c is the second most favorable HZ terrestrial planet for atmospheric characterization in transmission, assuming similar atmospheres, with Trappist-1 being the most favorable system. But since LP 890-9c is close to the inner edge of the conservative HZ, a water-rich atmosphere would boost its atmospheric signals compared to the cooler Trappist-1 planets in the HZ. While there are many possible atmospheric
models for exoplanets like LP 890-9c (see (Turbet et al., 2020; Fauchez et al., 2021) for a recent review
of models of Trappist-1), here we explore the specific question of how a rocky, Earth-like planet could evolve at LP 890-9c’s position and if the resulting spectra can be used to distinguish these scenarios and deepen our understanding of the conditions at the inner edge of the HZ."

It seems accurate masses are lacking for these new reports. Another report, Two temperate super-Earths transiting a nearby late-type M dwarf, [2209.02831] Two temperate super-Earths transiting a nearby late-type M dwarf (arxiv.org)

I note the radii shown at the arxiv.org site is somewhat larger than Earth size. Some 1.32 to 1.367 earth radii (same as exoplanet.eu site). Uranus and Neptune are closer to 4 earth radii size.

 

[Unclear Engineer]

Rod, what is the capability/probability that our current planet hunting equipment would be able to find a planet approximately the size of Earth orbiting about 1 AU from a star that is approximately the size and brightness of our Sun?

 

[rod]

Rod, what is the capability/probability that our current planet hunting equipment would be able to find a planet approximately the size of Earth orbiting about 1 AU from a star that is approximately the size and brightness of our Sun?

Good question. Using this site, The Extrasolar Planets Encyclopaedia (exoplanet.eu)

I found 193 exoplanets using MS ACCESS and MS SQL query. I selected for earth radii size between 0.8 to 1.1 earth radii. Most if not, all found using primary transit method. Stellar masses range 0.08 Msun to 1.35 Msun. Their distances however, packed in close to the parent stars. Semi-major axis range 0.00580 au to 0.68 au from the host stars. So, for the 193 I found, with radii in the 0.8 to 1.1 earth radii, they orbit close to the parent stars, inside of Venus and where Mercury is in our solar system.

 

[rod]

I did run the query using semi-major axis 0.9 au to 1.1 au. 66 exoplanets show up. The planets with masses are large. 6.2407 earth masses up to 18,115 earth masses Stellar masses run 0.039 Msun up to 2.17 Msun. It seems when I review these exoplanet sites, there is no place quite like home here

 

[rod]

Sometimes when I examine the exoplanet sites and using MS SQL queries, I am reminded of Star Trek. *To boldly go where no man has gone before. * However, when you get there, you may wish you never made that long trip

 

[Unclear Engineer]

Rod, thanks for the investigative effort and response.

Your results are what I was suspecting. Basically, we are detecting only large planets about 1 or more AU from their stars, and small planets can only be detected closer to stars, especially lighter mass stars. But detecting a twin of the Earth orbiting around a twin of the Sun does not seem so easy with the methods currently at our disposal. Have we assessed our current ability to detect transits of Earth sized planets for the nearest Sun-like stars? It seems that we can easily find the Sun-like stars, but not yet the Earth-like planets that may be orbiting them, especially if they don't transit their stars from our vantage point.

So I don't think we are yet in a good position with respect to using the current exoplanet data to try to quantify the parameter in the Drake Equation that deals with the number of Earth-like planets in our region of space/galaxy. So, we really don't yet know if "there's no place like home" in our local region of the galaxy.

 

[rod]

FYI. I used the criteria of 0.8 to 1.1 earth radii size and the NASA exoplanet archive site, NASA Exoplanet Archive (caltech.edu)

I found 204 exoplanets in this size range, very similar to the exoplanet.eu site results. Whether there are exoplanets with life (small or large forms) in our galaxy besides Earth, remains to be validated as true in science compared to the science for the round Earth vs. flat earth teaching today or the heliocentric solar system vs. the geocentric solar system, still in use by those in the flat earth community. Just my observation here.