More exoplanets found by TESS
Worlds without end: In confirming a candidate exoplanet previously discovered by TESS, astronomers have detected two more exoplanets orbiting the same star.
The transits TESS observed belong to GJ 357 b, a planet about 22% larger than Earth. It orbits 11 times closer to its star than Mercury does our Sun. This gives it an equilibrium temperature — calculated without accounting for the additional warming effects of a possible atmosphere — of around 490 degrees Fahrenheit (254 degrees Celsius). “We describe GJ 357 b as a ‘hot Earth,’” explains co-author Enric Pallé, an astrophysicist at the IAC and Luque’s doctoral supervisor. “Although it cannot host life, it is noteworthy as the third-nearest transiting exoplanet known to date and one of the best rocky planets we have for measuring the composition of any atmosphere it may possess.”
But while researchers were looking at ground-based data to confirm the existence of the hot Earth, they uncovered two additional worlds. The farthest-known planet, named GJ 357 d, is especially intriguing. “GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski at the Max Planck Institute for Astronomy in Heidelberg, Germany. “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”
Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size.
Even through TESS monitored the star for about a month, Luque’s team predicts any transit would have occurred outside the TESS observing window.
I think the results from TESS are soon going to overwhelm the general press. I myself had to check and make sure this story was about different exoplanets than the previous exoplanet discovery story from two days ago.
What is most interesting about these new exoplanets is their mass and size. TESS appears so far to be finding a lot of superEarths, something that Kepler did not do.
The support of my readers through the years has given me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Even today NASA and Congress refuse to recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation:
5. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.
Worlds without end: In confirming a candidate exoplanet previously discovered by TESS, astronomers have detected two more exoplanets orbiting the same star.
The transits TESS observed belong to GJ 357 b, a planet about 22% larger than Earth. It orbits 11 times closer to its star than Mercury does our Sun. This gives it an equilibrium temperature — calculated without accounting for the additional warming effects of a possible atmosphere — of around 490 degrees Fahrenheit (254 degrees Celsius). “We describe GJ 357 b as a ‘hot Earth,’” explains co-author Enric Pallé, an astrophysicist at the IAC and Luque’s doctoral supervisor. “Although it cannot host life, it is noteworthy as the third-nearest transiting exoplanet known to date and one of the best rocky planets we have for measuring the composition of any atmosphere it may possess.”
But while researchers were looking at ground-based data to confirm the existence of the hot Earth, they uncovered two additional worlds. The farthest-known planet, named GJ 357 d, is especially intriguing. “GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski at the Max Planck Institute for Astronomy in Heidelberg, Germany. “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”
Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size.
Even through TESS monitored the star for about a month, Luque’s team predicts any transit would have occurred outside the TESS observing window.
I think the results from TESS are soon going to overwhelm the general press. I myself had to check and make sure this story was about different exoplanets than the previous exoplanet discovery story from two days ago.
What is most interesting about these new exoplanets is their mass and size. TESS appears so far to be finding a lot of superEarths, something that Kepler did not do.
The support of my readers through the years has given me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Even today NASA and Congress refuse to recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation:
5. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.
Hmmm… Looking here at NASA’s Exoplanet Survey Archive https://exoplanetarchive.ipac.caltech.edu/docs/counts_detail.html
and I see these tables
Counts by Radius
R ≤ 1.25 R_Earth 400
1.25 < R ≤ 2 R_Earth 842
2 < R ≤ 6 R_Earth 1305
6 < R ≤ 15 R_Earth 418
15 R_Earth < R 156
Counts by Mass
M ≤ 3 M_Earth 28
3 < M ≤ 10 M_Earth 122
10 < M ≤ 30 M_Earth 88
30 < M ≤ 100 M_Earth 82
100 < M ≤ 300 M_Earth 196
300 M_Earth < M 337
I don't know how you define "superearths" but surely some of these would qualify. This is just for the confirmed planetary candidates in the original Kepler ("K1") mission. Counting both K1 and K2 possibilities, there have been about 2700 planets observed and confirmed, at least to the extent that they were mentioned in published scientific papers. There are another 3000 possible exoplanets in the Kepler data, observed but not yet confirmed. Analysis continues.
Meanwhile, for the newer satellite …..
Confirmed Planets Discovered by TESS 24
TESS Project Candidates 993
Candidates Yet To Be Confirmed 679
Lots of contenders which didn't make it last round ("false positives") — about one out of three in the TESS data. What I find interesting is not the number of superearths observed by TESS but the possible planets smaller than Earth; for comparison, none of the Kepler exoplanets were reported as smaller or less massive than Earth.
Note that these are conservative estimates, based on watching transits of targeted stars by these planets and guesstimating how much light they blocked. I.e., Earth, the star being observed, and the possible planets have to be more or less in a line for this to work. Planets too far from their suns to be noticed in the relatively short period they are under observation (virtually everything beyond Mars in our solar system, I’d gather) won’t be counted. Similarly, planets which orbit in a plane at an angle to the line between Earth and the star may not be observed (we might count these as exoPlutos). And it’s a nice question whether some planet-sized bodies might be concealed within extensive asteroid belts (exoJunos ? superCereses?) Also, there must be a zillion exoplanets the size of Mercury or smaller which simply aren’t big enough to register on our current instruments.
Plenty of planets yet to be see, in short.
Awesome, in the original sense of the word. When I was a kid we knew of nine planets and that was all. We had one or two fuzzy images of things that might have been accretion discs around other stars, but nothing more.
It’ll be interesting to see if the statistics shift as our imaging technology improves to the point where we don’t need to rely on transits to detect exoplanets.