Exoplanets and Astrobiology

Because they are so numerous, exoplanet candidates must be vetted. The validation process includes the following:

Jul 2019 Deeg H, Parviainen H, Multicolor Photometry for Exoplanet Candidate Validation
'....Radial velocity follow-up can be carried out only only for the most promising candidates around bright, slowly rotating stars....Thus, before devoting RV resources to candidates, they need to be vetted using cheaper methods, and, in the cases for which an RV confirmation is not feasible, the candidate's true nature needs to be determined based on these methods alone....We show that multicolor photometry can be used to estimate the amount of flux contamination and the true radius ratio.'
 
Transit Epochs: Uncertainty

We introduced ExoClock Project for amateur assistance of ephemerides and 1,000 exoplanet targets of James Webb telescope in post #9. More information on the importance of monitoring ephemerides is here:

Deeg H, et al, Orbital Period Refinement of CoRoT Planets with TESS Observations
'....The main motivation of this study has been to derive precise new ephemerides of the CoRoT planets, in order to keep these planets' transits observable for future generations of telescopes....In three cases (CoRoT-4b, 19b and 20b), transits would have been lost for ground observations, due to the large uncertainty in the previous ephemeris, have been recovered. Updates ephemerides permit transit predictions with uncertainties of less than 30 min for observations at least until the year 2030.'
 
This report aptly covers the introduction to exoplanet monitoring of ephemerides:

NASA
U. Virginia
U. California
SETI Institute
UNM Albuquerque
Jet Propulsion Laboratory
Edith Cowan University, Australia
M.I.T.
Citizen Scientist, UK
Stanford Online High School, etc.

21 May 2020 Utilizing Small Telescopes Operated by Citizen Scientists for Transiting Exoplanet Follow-Up
'....Using EXOTIC, we find that even a single 6-inch (15.24-cm) telescope cam produce high precision data....A network of smaller telescopes (~16 >6-inch telescopes) could rapidly respond to new discoveries and high priority bright targets with large transit depths and monitor them, allowing larger telescopes to spend their time on other targets (e.g., Earth-sized planets transiting dim M-dwarf stars).'
 
Within the next six months, astonishing new finds in Astronomy will intensify. When the Extremely Large Telescope in Chile gets first light in 2027, along with the James Webb telescope and others, will take a much closer look at prime candidate expolanets such as Ross 128b, one of the best for habitability.

Extremely Large Telescope (Atacama Desert)

Any U.S. scientist proposing a great idea could get viewing time on the ELT, this trajectory which will span two hemispheres, the federally-funded transformation of science.

Ross 128b

The ELT will also look at Proxima B in Centauri.

Proxima Centauri B
 
Within the next six months, astonishing new finds in Astronomy will intensify. When the Extremely Large Telescope in Chile gets first light in 2027, along with the James Webb telescope and others, will take a much closer look at prime candidate expolanets such as Ross 128b, one of the best for habitability.

Extremely Large Telescope (Atacama Desert)

Any U.S. scientist proposing a great idea could get viewing time on the ELT, this trajectory which will span two hemispheres, the federally-funded transformation of science.

Ross 128b

The ELT will also look at Proxima B in Centauri.

Proxima Centauri B


Both Ross 128b and Proxima Centauri B orbit red dwarfs.

Red dwarfs all have significant variability. Most of the stars in our galaxy are red dwarfs. It is hard to have life on an orbiting planet when the temperature is 70F one day and 370F the next.
 
This is the instrument that will analyze the atmospheres of exoplanet candidates:

HIRES
 
Both Ross 128b and Proxima Centauri B orbit red dwarfs.

Red dwarfs all have significant variability. Most of the stars in our galaxy are red dwarfs. It is hard to have life on an orbiting planet when the temperature is 70F one day and 370F the next.
When one lives in New Mexico, one becomes aware of this temperature phenomenon which is not that devastating. That's why Navajo made the best blankets. Red dwarfs were among the first ones Deeg studied. Deeg and badger visited the Devil's Backbone in the Galisteo Basin, New Mexico, where the Pueblos (Pueblo Blanco) watched for approaching buffalo. No doubt the night sky intrigued them, for these rocks sport interesting petroglyphs. Knowledge about red dwarfs cannot be separated from the search for exoplanets.
 
When one lives in New Mexico, one becomes aware of this temperature phenomenon which is not that devastating. That's why Navajo made the best blankets. Red dwarfs were among the first ones Deeg studied. Deeg and badger visited the Devil's Backbone in the Galisteo Basin, New Mexico, where the Pueblos (Pueblo Blanco) watched for approaching buffalo. No doubt the night sky intrigued them, for these rocks sport interesting petroglyphs. Knowledge about red dwarfs cannot be separated from the search for exoplanets.


If we are going to spend our time looking for planets that support life then we can pretty much forget about Red Dwarfs because they are not stable stars. Life needs a degree of temperature stability and Red Dwarfs don't meet that criteria.

Our sun is a type G White Dwarf. Only about 3% of the stars in the galaxy are like ours. They spent several years studying sun like stars and discovered that they are also variable and that our sun is unusually stable.

Life in the universe may be much rarer than we could possibly imagine.
 
If we are going to spend our time looking for planets that support life then we can pretty much forget about Red Dwarfs because they are not stable stars. Life needs a degree of temperature stability and Red Dwarfs don't meet that criteria.

Our sun is a type G White Dwarf. Only about 3% of the stars in the galaxy are like ours. They spent several years studying sun like stars and discovered that they are also variable and that our sun is unusually stable.

Life in the universe may be much rarer than we could possibly imagine.
For example, It's probably not a good idea to dismiss red dwarfs that are tidally locked. Kristen Menou (Columbia University Astronomy) talks about this in NASA News (17 Jul 2013) in "Water-Trapped Worlds." He also says in that report, "These worlds may be among the first that we are able to probe and characterize for habitability."

Menou also has a youtube video, at timepoint 7:50 he states that the world 'habitable' is "the most ambiguous word in astronomy." At timepoint 11:30 he introduces the intriguing Trappist 1 system:

Menou: Cold Our There, Eh?
 
The argument for variability as a negative trait of a red dwarf is problematic. If a red dwarf can produce flares that double their brightness in minutes, a tidally-locked dwarf with a "twilight zone" although close to the star is still worth studying because

1. of the improvements of the technology that will be used in sending probes to the closest red dwarfs, undoubtedly benefitting future exoplanet expeditions.

2. extremophile evolution of microorganisms on other expolanets than the one being probed that may have volcanic activity and are tidally locked. Has such a red dwarf or other exoplanet planet yet been described? TESS shows that the flares occur at the poles, sparing the planet.
TESS / High Latitude Flares
https://www.universetoday.com/15210...ares-out-the-poles-sparing-their-planets-from destruction/
 
So whether or not the URL works, the fact remains: red dwarfs flare at the poles.
 
The best bet for now is to refrain from separating the concept of polar flares from either the host star or its red dwarf.
 
Here is an example of a citizen scientist helping professional astronomers while discovering new exoplanets:

Citizen Scientists Spot Jupiter-Like Planet in NASA TESS Data
'....Tom Jacobs of Bellevue, Washington....the newly discovered planet was hiding in data from NASA's Transiting Exoplanet Satellite Survey....TOI-2180b.'

TOI-2180b is a gas giant that orbits a G-type star (nuclear fusion).
 

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