Exoplanet Stats

Page 2 - Seeking answers about space? Join the Space community: the premier source of space exploration, innovation, and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier.
Here's an update, with some minor improvements (header info of User settings).

[There are 128 total HZ exoplanets, but this list meets the User's settings (at top)]



Although all these are in the HZ (Habitable Zone), there are only 3 exoplanets that meet all three criteria of what likely, using today's standards, qualify for an HZ exoplanet.

TOI-700d is the first. [It is in reddish highlight because it is too far south to be observed from the User's location (Tuscaloosa) at any time.

Exoplanet.eu is still just under 5k exoplanets.
 
  • Like
Reactions: Catastrophe
Oct 23, 2019
49
20
1,535
Visit site
Oh .I didn't know Helio downloaded the exoplqnet data then crunched it with Excel
...now I understand a little better the process of how he put those spreadsheets together. Sounds like he is manually typing on the books he reads to a catalog though so he is doing his own data entry too on that. I'm digging this idea of cataloging books in a spreadsheet or some other way.
 
Oh .I didn't know Helio downloaded the exoplqnet data then crunched it with Excel.

Yes. The exoplanet.eu website has a catalog that, with one click, will download all their data into a format (.csv) that Excel can easily handle. A simple copy and paste will put it into an Excel tab where the VBA code, written in my program, can crunch all the data into useful information.

The HZ equations are straight-forward and pretty simple, really. It only takes seconds for the program to go through the ~ 5000 planets to yield many different results, especially those thar are in the HZ, and done so colorfully. Excel (VBA) was a bit cryptic at first to learn but it isn't that hard if one is willing to make use of Youtube to get the right command or formula.

BTW, this program I'm pleased to make available to all that request it. Simply send me a private message (envelope icon at top right next to your avatar) that has your email.

Cat tried it and it seems you don't have to be on the Microsoft monthly payment plan to use it.

...now I understand a little better the process of how he put those spreadsheets together. Sounds like he is manually typing on the books he reads to a catalog though so he is doing his own data entry too on that. I'm digging this idea of cataloging books in a spreadsheet or some other way.
Yes, but Word is almost as useful.

If you have over, say, 100 books, I recommend Excel, or Word. I have many more than this, though I just donated about 150 as we are moving and I'm getting less active so I doubt I would read them or use them for references.

Having a category can greatly improve finding them if you've forgotten the title or author. I also include the publication date.
 
  • Like
Reactions: Catastrophe
Yes Helio, 5001 are listed as confirmed now. This entry caught my eye :) The Extrasolar Planet Encyclopaedia — TOI-2180 b (exoplanet.eu)

Looking at the exoplanet mass, semi-major axis, and host star mass is what I noticed. I did a MS SQL query for semi-major axis between 0.5 and 1.1 au. 226 exoplanets reported for duty, quite a number with large masses like Jupiter or more. Very different than what we see in our solar system with Venus and Earth here.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Rod, that is an interesting point. Of course, many Jupiter size planets would look very much like Earth or Venus (themselves not exactly congruent ;) ) at other points in the development of their stars. (OR Mercury or Mars, for that matter).

Helio, please, (and/or Rod), Is any account taken when making such comments as the what might be the case at other development stages of their stars?

Please pardon my ignorance in this matter, which is not currently close to my core interests.

Cat :) :) :)
 
  • Like
Reactions: Helio and rod
Rod, that is an interesting point. Of course, many Jupiter size planets would look very much like Earth or Venus (themselves not exactly congruent ;) ) at other points in the development of their stars. (OR Mercury or Mars, for that matter).

Helio, please, (and/or Rod), Is any account taken when making such comments as the what might be the case at other development stages of their stars?

Please pardon my ignorance in this matter, which is not currently close to my core interests.

Cat :) :) :)

Cat, in answer to *Is any account taken when making such comments as the what might be the case at other development stages of their stars?*

It seems so, however I note with much difficulty like this report. ALMA constraints on assembly of Core Accretion planets, https://arxiv.org/abs/2204.05372, and reference paper, https://arxiv.org/pdf/2204.05372.pdf, 11-April-2022, 17-pages.

This was refreshing for me to see.

"1 INTRODUCTION A planet formation theory is a set of equations describing evolution of planet variables, such as its mass Mp, separation a, metallicity zp, etc., inside the parent protoplanetary disc. Protoplanetary disc evolution is itself a field of intense research (Williams & Cieza 2011; Alexander et al. 2014), with data indicating a tremendous variety in protoplanetary disc properties even for stars of similar mass, age, and environment (e.g., Manara et al. 2017; Andrews 2020). Furthermore, exoplanetary data are very strongly dominated by planets orbiting stars much older than ∼ 10 Myr (e.g., Winn & Fabrycky 2015). These stars have lost all signs of their primordial discs from which they grew. This makes it impossible to ascertain the properties of the disc in which a given planet formed. We also face similar uncertainties for the planets in the Solar System..."

It is clear that the *primordial discs* for the majority of exoplanets documented today, is not seen in astronomy but assumed to be there in the unobserved past *to fit with the theory* and computer simulations using accretion discs around *young stars*. This is true for the solar nebula and how the MMSN (Minimum Mass Solar Nebula) is used in computer models to explain how our solar system formed. Seldom do I find this clearly acknowledged. The computer simulations commonly create numerous unobserved objects in nature today, a classic example is Theia used in the giant impact model to explain the origin of our Moon or a variety of proto-planetary cores near 5 to 10 earth masses to simulate the evolution of ice giants like Uranus or Neptune, even Jupiter, Saturn. We do not see the MMSN in the ecliptic today or proto-planets or even planet embryos in our solar system, language found in the computer models.

So Cat, the effort is there but explaining how a 1.1 solar mass star, perhaps near 8 Gyr old with unobserved primordial disc today, gave birth to an exoplanet near 2.76 Jupiter mass in a location in the system where Venus and Earth are in our solar system moving around the Sun, 1 solar mass star is challenging. Somehow these interesting exoplanet configurations managed to not appear in our solar system, and thus, somehow you and I can live and read interesting issues like this :)
 
For listings or cataloging, I prefer Access (or the LibreOffice equivalent, Base). But Excel (LibreOffice Calc) is like the greatest math tool. I have a number of files that does astronomical equations, that once ‘programmed’ (not difficult), gives results up to 16 decimal precision. Even does iterations, geometry, logs, trig, and the like. It also does perfect calendar and clock math from 1 January 1900 on. I created one page that does the calendar for any date from Julian Day 1 ( 4713 BCE) to present.
 
  • Like
Reactions: Helio

Catastrophe

"Science begets knowledge, opinion ignorance.
Rod, re yr post #33,
"The computer simulations commonly create numerous unobserved objects in nature today, a classic example is Theia used in the giant impact model to explain the origin of our Moon or a variety of proto-planetary cores near 5 to 10 earth masses to simulate the evolution of ice giants like Uranus or Neptune, even Jupiter, Saturn."

I must be careful not to cross the intentions of the much respected OP, who stated:
"It might be nice to have a thread on the latest exoplanet data presentations."

I hope exoplanet data include cognisance of the position of the exoplanet within the cycle of its star, as well, as you so effectively point out, the effects of late (or any other) bombardments by 'third party' bodies.

I do not wish to add anything further which might obfuscate Helio's excellent work, so I will take my leave. Nonetheless, finally, just a few words, please, on progression through time, with its possible (or probable) effects. Many stars will change in size and mass; gravitational interactions will change; satellites will no longer be held in their former orbits - as planets will forsake their previous 'habits'. But, enough, we can leave the future billions of years to run their courses. I have no further comments to add.

Cat :) :) :)
 
Yes Helio, 5001 are listed as confirmed now. This entry caught my eye :) The Extrasolar Planet Encyclopaedia — TOI-2180 b (exoplanet.eu)
Yes. I would consider this one of those low-hanging fruits. Big exoplanets are just easier to see than small ones, whether by transit or by Doppler.

My prog. shows it is ~85% the HZ width inside the inner limit. So it is too hot for an exoplanet for liquid water. But it does have a fairly high e value, so it will be a little cooler on average, just not likely cool enough.

Looking at the exoplanet mass, semi-major axis, and host star mass is what I noticed. I did a MS SQL query for semi-major axis between 0.5 and 1.1 au. 226 exoplanets reported for duty, quite a number with large masses like Jupiter or more. Very different than what we see in our solar system with Venus and Earth here.

I see I never gave the size distribution for the first 25 size bins (size categories), so here 'tis...

 
  • Like
Reactions: Catastrophe
Helio, please, (and/or Rod), Is any account taken when making such comments as the what might be the case at other development stages of their stars?
Yeah, that's a good question. On the one hand the planets form from the early protostar's accretion disk, so planets are almost as old as the stars, unless captured from neighboring systems.

But astronomers have described their orbital history as the action of a pin ball machine. :) This may be like herding cats in trying to determine which one will go where, or how they got to where they are. Perhaps there's a video of the current model for the solar system that seems to fit all but perhaps Pluto.
 
  • Like
Reactions: Catastrophe
So Cat, the effort is there but explaining how a 1.1 solar mass star, perhaps near 8 Gyr old with unobserved primordial disc today, gave birth to an exoplanet near 2.76 Jupiter mass in a location in the system where Venus and Earth are in our solar system moving around the Sun, 1 solar mass star is challenging. Somehow these interesting exoplanet configurations managed to not appear in our solar system, and thus, somehow you and I can live and read interesting issues like this :)
Yes.

Another thing I think that is a big factor is the radial disk mass distribution in the early phases of formation. Recall that most stars form with one or more stars, so there should be a wide range of mass distributions within disks, not to mention the disturbing action from a very close protostar (future binary) affecting those density changes.

Clouds seem to collapse only under significantly disturbing conditions, including supernovae and super sonic flows within the cloud. These make for some very mess equations on how to make any one set of messy things to settle into something as nice as a solar system.
 
  • Like
Reactions: Catastrophe

Catastrophe

"Science begets knowledge, opinion ignorance.
Helio,
"explaining how a 1.1 solar mass star, perhaps near 8 Gyr old with unobserved primordial disc today, gave birth to an exoplanet near 2.76 Jupiter mass in a location in the system where Venus and Earth are in our solar system moving around the Sun, 1 solar mass star is challenging."

I am still battling with 'Nice' and related - talk about hurting heads.

"Is that a Saturn I see before me, its Rings toward my hand?"
To grab, or not to grab - that is the question."

Remember, I lived 6 miles from Stratford-upon-Avon.

Cat :)
 
  • Like
Reactions: Helio
Here's another update. This one includes the change in the HZ due to eccentricity. There is a paper that demonstrates a significant shift outward in the HZ limits for an eccentric orbit of e = 0.4. [Oddly, the greater amount of time traveled in the outer part of the orbit where it will become cooler, doesn't offset the hotter period during the inner half (periapsis) that is travelled faster but much hotter (inv. square law for radiation).

The program now allows the User to either choose their own adjustment "fudge" factors or enter their adjustment percent for an e=0.4, which then calculates the HZ limit change given the eccentric orbit for each exoplanet (linear model).

This bumps the number of HZ exoplanets by almost 40%! It adds one more to the total for those in the HZ for a planet similar to Earth is size.



 
Last edited:
  • Like
Reactions: Catastrophe
Now we have 5020 exoplanets at the .eu site. We also have another report indicating defining the HZ may involve more to find a earth like exoplanet and habitable. Not as easy it may look.

Ref - Team finds younger exoplanets are better candidates when looking for other Earths, https://phys.org/news/2022-05-team-younger-exoplanets-candidates-earths.html

"As the scientific community searches for worlds orbiting nearby stars that could potentially harbor life, new Southwest Research Institute-led research suggests that younger rocky exoplanets are more likely to support temperate, Earth-like climates...However, even within this so-called "Goldilocks zone," planets can still develop climates inhospitable to life..."

Reference paper, Mantle Degassing Lifetimes through Galactic Time and the Maximum Age Stagnant-lid Rocky Exoplanets Can Support Temperate Climates, https://iopscience.iop.org/article/10.3847/2041-8213/ac6596#apjlac6596t2, 03-May-2022. “Abstract The ideal exoplanets to search for life are those within a star's habitable zone. However, even within the habitable zone, planets can still develop uninhabitable climate states. Sustaining a temperate climate over geologic (∼gigayear) timescales requires a planet to contain sufficient internal energy to power a planetary-scale carbon cycle. A major component of a rocky planet's energy budget is the heat produced by the decay of radioactive elements, especially 40K, 232Th, 235U, and 238U. As the planet ages and these elements decay, this radiogenic energy source dwindles..."

My observation. In the reference paper cited, 17 exoplanets are noted in the study. "Table A2. Sample of Likely Solid Rocky Planets", table A2 lists some properties for these 17 exoplanets. TRAPPIST-1 f is the smallest mass listed, 1.039 earth mass, density 5.0 g cm^-3 with 7.6 Gyr age. The largest mass exoplanet on the table, Kepler-197 c, 5.3 earth mass, density 15.6 g cm^-3. The ages listed range 1.4 Gyr - 11 Gyr. Temperature is provided too in the table. 199 K - 1224 K. The first exoplanet on the table is K2-36 b, http://exoplanet.eu/catalog/k2-36_b/, a = 0.0223 au, P= 1.422614 day. Searching for an earthlike exoplanet is very difficult and rocky is very difficult.
 
  • Like
Reactions: Helio
A recent article (Star Date?) emphasized the importance of phosphines, also limiting our chances, perhaps.

Of the 5020, only 9 are found in the HZ of a size comparable to Earth. Venus is also in the HZ, IIRC, showing us more reason to suspect problems.
 
  • Like
Reactions: rod
Now the .eu site shows 5029 exoplanets :) I did some MS SQL query and descriptive stats.

2342 exoplanets with radii <= 3.0 earth radii. 252 exoplanets with masses Uranus to Saturn type sizes (12.75 - 95.35 earth masses or 0.04 Jupiter to 0.3 Jupiter mass), and 496 Jupiter types with masses 0.5 Jupiter - 3.0 Jupiter.

Comparing to our solar system configuration and these exoplanet configurations is very interesting :)
 
  • Like
Reactions: Helio
Now the .eu site shows 5029 exoplanets :) I did some MS SQL query and descriptive stats.

2342 exoplanets with radii <= 3.0 earth radii. 252 exoplanets with masses Uranus to Saturn type sizes (12.75 - 95.35 earth masses or 0.04 Jupiter to 0.3 Jupiter mass), and 496 Jupiter types with masses 0.5 Jupiter - 3.0 Jupiter.
It's surprising to me that almost half of the exoplanets are <= 3 Earth radius. The "low-hanging fruit" for astronomers are the larger planets simply because they are easier to detect.

The even greater challenge is to detect those of greater distances from their host star since the statistical probability of seeing these in transit is much less, and the smaller they are, the more they fade into the noise. Another drawback to finding them is that their orbit takes years so the opportunities to catch them is much less.

I checked with the change in the size distribution from February and there is essentially no change for the smaller radii.

Here is a current distribution:
 
  • Like
Reactions: Catastrophe and rod
The following is something new I'm trying in my program. The database from exoplanet.eu does not attempt to assign a star type even when temperatures are stated. This isn't wrong since not all are main sequence stars, so errors are likely if one sets a star type based on temperature.

But if we look at a range of planet radii to 5.0 that of the Earth radius, we will only find 387 planets of a known star type.

So, if we guess the star type based on their known temperature, we get a great deal more in number -- 2,712. [There are only about 40 planets that cannot be classified up to 5.0 Earth radius.]

The following is the radii distribution by star type using the guess method.

 
Here is a Space.com report on how the majority of the HZs may qualify as overlapping with the "Venus zone" -- a nightmare scenario for exoplanets.

Too little, however, is known about how Venus became so incipient and how it developed its run-a-way greenhouse effect, so perhaps this VZ will be far more limited in size once we understand things better.

It's obvious there is no assurance that the Venus zone may dominate most HZs given the fact the Earth is deep within the Venus zone for our Sun.
 
  • Like
Reactions: Catastrophe and rod