<p>We know that peak of star formation already passed</p>
<p>10.1146/annurev-astro-032620-021910<br />
<a href="https://i.sstatic.net/NhRgz.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/NhRgz.png" alt="enter image description here" /></a></p>
<p>and it looks like peak of planet formation occurred slightly after formation of Earth</p>
<p>10.1017/S1473550415000208
<a href="https://i.sstatic.net/u2fQI.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/u2fQI.gif" alt="enter image description here" /></a></p>
<p>Even if we ignore possibility of life around red dwarfs that may live for trillions of years (as there a numerous problems with this - for example core of the planet cools much quicker), there is still possibility that planet formation will go for tens and hundreds of billions of years at reasonable rates (long-tail of the distribution) and that most planets will be formed in the future.</p>
<p>Can we exclude/prove this long-tailed possibility?</p>

CC BY-SA 4.0
2021-11-09T06:53:47.680Z
Planet formation is a process that requires enormous amounts of side-product material from the star formation process to be present. So it is no surprise that the PF time should coincide with the SF time. There might be some late stages of PF, such as when binary stars evolve into Roche-lobe overflowing systems (e.g. Pulsar planets), but those episodes should be very bursty. For the entire main sequence lifetime of stars, there shouldn't be any PF activity, except if you count dynamical instabilities.
AtmosphericPrisonEscape
CC BY-SA 4.0
2021-11-09T13:27:18.603Z
Planet formation must tally with star formation since planets form around stars at the time of star formation. Can you please say where you go the plots from and what they are supposed to represent?
ProfRob
CC BY-SA 4.0
2021-11-12T06:41:51.353Z
I don't think we know the PF history to the accuracy this plot seems to imply. There are no observational traces of PF, so this is all based on models. These are calibrated by other observations, namely the data for exo-planets, but those are still rather biased by the detection methods -- preferentially detecting short-period planets, quite unlike Jupiter or Saturn (who make most of the planet mass in the Solar system).
Walter
CC BY-SA 4.0
2021-11-12T06:42:59.283Z
@ProfRob Yes, PF occurs during SF, but with a probability (relative rate) that depends on metallicity.
Walter
<exoplanet><star-formation><earth-like-planet><distribution-function>
Can distribution of stars / planets formation be a long-tailed one?
Vashu
# Can distribution of stars / planets formation be a long-tailed one?

(Asked by: username_0 on 2021-11-09)

We know that peak of star formation already passed

10.1146/annurev-astro-032620-021910  
[![enter image description here](https://i.sstatic.net/NhRgz.png)](https://i.sstatic.net/NhRgz.png)

and it looks like peak of planet formation occurred slightly after formation of Earth

10.1017/S1473550415000208
[![enter image description here](https://i.sstatic.net/u2fQI.gif)](https://i.sstatic.net/u2fQI.gif)

Even if we ignore possibility of life around red dwarfs that may live for trillions of years (as there a numerous problems with this - for example core of the planet cools much quicker), there is still possibility that planet formation will go for tens and hundreds of billions of years at reasonable rates (long-tail of the distribution) and that most planets will be formed in the future.

Can we exclude/prove this long-tailed possibility?

**Tags:** exoplanet, star-formation, earth-like-planet, distribution-function

> **Comments:**
> **username_1**: Planet formation is a process that requires enormous amounts of side-product material from the star formation process to be present. So it is no surprise that the PF time should coincide with the SF time. There might be some late stages of PF, such as when binary stars evolve into Roche-lobe overflowing systems (e.g. Pulsar planets), but those episodes should be very bursty. For the entire main sequence lifetime of stars, there shouldn't be any PF activity, except if you count dynamical instabilities.  
> **username_2**: Planet formation must tally with star formation since planets form around stars at the time of star formation. Can you please say where you go the plots from and what they are supposed to represent?  
> **username_3**: I don't think we know the PF history to the accuracy this plot seems to imply. There are no observational traces of PF, so this is all based on models. These are calibrated by other observations, namely the data for exo-planets, but those are still rather biased by the detection methods -- preferentially detecting short-period planets, quite unlike Jupiter or Saturn (who make most of the planet mass in the Solar system).  
> **username_3**: @username_2 Yes, PF occurs during SF, but with a probability (relative rate) that depends on metallicity.  

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## 0 answers

