How do planets form? A 'baby Jupiter' hundreds of light-years away offers new clues

[Admin]

In new research, we have spotted a hot, Jupiter-like gas giant in the process of forming around a star about 500 light-years from Earth.

How do planets form? A 'baby Jupiter' hundreds of light-years away offers new clues : Read more

 

[rod]

Interesting exoplanet AB Aurigae b. I dug a bit into AB Aurigae b. http://exoplanet.eu/catalog/ab_aur_b/, using these properties I calculate P = 5.8632E+02 years or 2.1415E+05 days. In 1 Gyr period, 1.7056E+06 revolutions completed around the host star (the star is considered about 0.002 Gyr). The 9 Mjup exoplanet = 2.8604E+03 or 2860 earth masses. Using the MMSN for 2.4 solar mass star, a postulated primordial disk mass = 7.991028E+03 or close to 8,000 earth masses. I did not find a specific protoplanetary disk mass size presented in the 51-page report, https://arxiv.org/ftp/arxiv/papers/2204/2204.00633.pdf

When reports are published about *young stars* with disks, I think the total gas and dust mass estimate should be clearly presented too, including the size, example in AU units, and disclose clearly what new simulations use as well.

My note from the 51-page arxiv paper, "Table 1| System Properties" shows mass estimates for this postulated exoplanet range 9 Jupiter mass up to near 130 Jupiter mass or some 41,000 earth mass or possibly larger. AB Aur star is reported to show a massive disk in other reports and as the paper states, "Optical to near infrared (IR) scattered light imaging of its massive protoplanetary disk reveals numerous spiral arms on 200--500 au scales32-34".

My note. This link reports gas mass in some areas of AB Aur estimated at 4.2E-4 Msun so total gas and dust disk mass could be 1.398360E+04 earth masses (nearly 14,000 earth masses), https://arxiv.org/pdf/1906.11638.pdf

This NASA ADS Abstract from June 2015 reports a disk mass estimated at 0.01 Msun for 110 au out to 550 au, https://ui.adsabs.harvard.edu/abs/2015A&A...578A..81P/abstract, this is ~ 3329 earth masses.

Okay, I went geeky here on the stats for the report However, geeky can be summarized quickly. The mass estimate for AB Aur b seems to range from 9 Mjup up to nearly 130 Mjup. The disk mass size could be all over the map, perhaps nearly 14,000 earth masses and as low as close to 3300 earth masses. Using the canonical MMSN for our Sun and applying to a 2.4 Msun star, could result in a disk mass near 8,000 earth masses. Running simulations for variables like this could be fun

 

[Helio]

The problem in all models comes in guessing the initial conditions. It’s not too surprising that it may take lots of detailed knowledge of proto systems to eventually have a great model. Last I read, we don’t actually have one for our solar system, but this may due only to trying to account for Pluto, IIRC.

 

[billslugg]

This might be a good target for JWST. It can look through dust to see what is inside.

 

[Helio]

This might be a good target for JWST. It can look through dust to see what is inside.

Is the ALMA data as good or better than what the JWST might see?

I wonder how well the JWST can see into these systems. If the dust is significant (earlier formation periods), it may not penetrate this cloud, or am I wrong?

 

[billslugg]

Hubble has a range .1 micron to 2.5 microns - this is UV/visible/near-infrared spectrum
JWST has a range .6 microns to 28.8 microns - this is near/far infrared.
ALMA has a range of 600 microns to 10,000 microns, this is millimeter wavelengths.
JWST and ALMA will be sensitive to different sized dust particles. I don't know exactly how this works.