Ratio of Earth-Sized exoplanets to other sizes of exoplanet?

  • B
  • Thread starter Cerenkov
  • Start date
  • #1
167
22
Hello.

In this issue of the American Scientist magazine,
https://www.americanscientist.org/magazine/issues/2018/september-october, there's an article by Dominik Kraus of the Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiation Physics about the internal composition of the planets Uranus and Neptune. In the opening paragraphs he writes...

The number of planets similar in size to Uranus and Neptune that have been found in the galaxy is roughly nine times greater than the number of much larger planets similar in size to Jupiter and Saturn.


This statistic interests me and I was wondering if other members of PF could help me explore further.
Are there any papers or articles that give other ratios? That is, the ratios of Jovians, Ice-Giants, Super-Earths and Earth-sized exoplanets to each other? Any help given would be appreciated, though I should point out that I'm coming at this from a basic level.

Thank you,

Cerenkov.
 

Answers and Replies

  • #2
494
197
Such statistic is in general very unreliable - because of observational bias. Larger planets are simply much easier to find. The Kepler survey has delivered less biased dataset for Neptune-sized planet and larger though, and i think reference you cited is referring specifically to Kepler data.

You can also see
https://en.wikipedia.org/wiki/Initial_mass_function
which shows opinions wildly different even to the jupiter-brown dwarf range.
 
  • Like
Likes jim mcnamara, TEFLing and davenn
  • #3
167
22
Thanks trurle.

Well, I suppose if I'm to pursue my interest further I'll just have to contact Dominik Kraus directly and ask him where he derived his ratio from.

Cerenkov.
 
  • #4
stefan r
Science Advisor
912
297
...Larger planets are simply much easier to find. ...

That would suggest that the number neptunes is higher than the 10:1 ratio reported.

...

This statistic interests me and I was wondering if other members of PF could help me explore further.
Are there any papers or articles that give other ratios? That is, the ratios of Jovians, Ice-Giants, Super-Earths and Earth-sized exoplanets to each other? Any help given would be appreciated, though I should point out that I'm coming at this from a basic level.
....

This website as the full list. You can sort by characteristic like mass or radius. I think wikipedia is more fun to read. You can surf directly to articles.

Planets do not cooperate and fall into neat categories. For example kepler 138b has gas planet densities but Earth like mass.
 
  • #5
167
22
Many thanks, Stefan!

I can now work with these data and discover the ratios for myself.

Cerenkov.
 
  • #8
167
22
Hey TEFling!

Not 5 minutes ago I ordered Yaqoob's book on Amazon.

It'll arrive, not just in time for Xmas, but more importantly, in time for me to better understand the TESS data release scheduled for January.

https://www.nasa.gov/ames/tess-pipeline

And that result is all down to you.

upload_2018-12-1_20-8-44.png
 

Attachments

  • upload_2018-12-1_20-8-44.png
    upload_2018-12-1_20-8-44.png
    359.9 KB · Views: 279

Related Threads on Ratio of Earth-Sized exoplanets to other sizes of exoplanet?

Replies
3
Views
1K
Replies
44
Views
5K
Replies
8
Views
1K
Replies
14
Views
1K
  • Last Post
2
Replies
29
Views
7K
Replies
2
Views
1K
Replies
4
Views
343
Replies
5
Views
1K
  • Last Post
Replies
22
Views
4K
  • Last Post
Replies
8
Views
1K
Top