Carnegie: More Gas Giants Will Be Found Orbiting Sun-like Stars

[bystander]

Prediction: More Gas Giants Will Be Found Orbiting Sun-like Stars
Carnegie Institution for Science | 2017 Feb 21

[img3="Boss’ model of a planet-forming disk, which demonstrates that gas giant planets could be found orbiting Sun-like stars at distances similar to Jupiter and Saturn. The disk extends from 4 to 20 times the distance of the Earth from the Sun. You can see the spiral arms forming in the midplane of the disk. The disk instability theory suggests that gas giant planets can form from the clumps seen in the densest regions of the spiral arms."]https://carnegiescience.edu/sites/carne ... 00x800.jpg[/img3][hr][/hr]

New planetary formation models from Carnegie’s Alan Boss indicate that there may be an undiscovered population of gas giant planets orbiting around Sun-like stars at distances similar to those of Jupiter and Saturn. ...

The population of exoplanets discovered by ongoing planet-hunting projects continues to increase. These discoveries can improve models that predict where to look for more of them.

The planets predicted by Boss in this study could hold the key to solving a longstanding debate about the formation of our Solar System’s giant planets out of the disk of gas and dust that surrounded the Sun in its youth.

One theory holds that gas giants form just like terrestrial planets do—by the slow accretion of rocky material from the rotating disk—until the object contains enough material to gravitationally attract a very large envelope of gas around a solid core. The other theory states that gas giant planets form rapidly when the disk gas forms spiral arms, which increase in mass and density until distinct clumps form that coalesce into baby gas giant planets.

One problem with the first option, called core accretion, is that it can’t explain how gas giant planets form beyond a certain orbital distance from their host stars—a phenomenon that is increasingly found by intrepid planet hunters. However, models of the second theory, called disk instability, have indicated the formation of planets with orbits between about 20 and 50 times the distance between the Earth and the Sun. ...

The Effect of Protoplanetary Disk Cooling Times on the Formation
of Gas Giant Planets by Gravitational Instability - Alan P. Boss

• Astrophysical Journal 836(1):53 (10 Feb 2017) DOI: 10.3847/1538-4357/836/1/53
  arXiv.org > astro-ph > arXiv:1701.04892 > 17 Jan 2017

[BDanielMayfield]

I hope, for the frequency of truly Earth like planets, that this Boss' prediction pans out. It has been suggested that Jupiter and Saturn played an important role in helping our planet to be so life friendly.

However, contrary to Boss et al's prediction, which is based on a theory of how gas giants form, actual data on occurrence rates of Jupiter analogs (gas giant planets orbiting Sun like stars in an orbit similar to Jupiter's) are telling a different story. Rowan et al (2015), arxiv:1512.00417 reported on a Keck RV survey of 1,122 stars. They found only one Jupiter analog orbiting a sun like star. They concluded: "we estimate the frequency of Jupiter analogs across our survey at approximately 3%."

Bruce

[bystander]

...
actual data on occurrence rates of Jupiter analogs (gas giant planets orbiting Sun like stars in an orbit similar to Jupiter's) are telling a different story. Rowan et al (2015), arxiv:1512.00417 reported on a Keck RV survey of 1,122 stars. They found only one Jupiter analog orbiting a sun like star. They concluded: "we estimate the frequency of Jupiter analogs across our survey at approximately 3%."

http://asterisk.apod.com/viewtopic.php?t=35453

[BDanielMayfield]

Wow, and thanks for adding the hyperlink in the quotation bystander. I say wow because your viewtopic link tells the tale of the lead author of the paper I refenced, entitled "The Lick-Carnegie Exoplanet Survey: HD 32963 - A New Jupiter Analog Orbiting a Sun-like Star", a young lad named Dominick Rowan (not the British actor who played Doc Martin) who was a high school senior when this paper came out

Bruce