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arXiv · 2210.02420

Most planets might have more than 5 Myr of time to form

Susanne Pfalzner·Shahrzad Dehghani·Arnaud Michel
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Abstract

The lifetime of protoplanetary disks is a crucial parameter for planet formation research. Observations of disk fractions in star clusters imply median disk lifetimes of 1 -- 3 Myr. This very short disk lifetime calls for planet formation to occur extremely rapidly. We show that young, distant clusters ($\leq$ 5 Myr, $>$ 200 pc) often dominate these types of studies. Such clusters frequently suffer from limiting magnitudes leading to an over-representation of high-mass stars. As high-mass stars disperse their disks earlier, the derived disk lifetimes apply best to high-mass stars rather than low-mass stars. Including only nearby clusters ($<$ 200 pc) minimizes the effect of limiting magnitude. In this case, the median disk lifetime of low-mass stars is with 5 -- 10 Myr, thus much longer than often claimed. The longer timescales provide planets ample time to form. How high-mass stars form planets so much faster than low-mass stars is the next grand challenges.

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Susanne Pfalzner, Shahrzad Dehghani, Arnaud Michel. 2022-10-05. Most planets might have more than 5 Myr of time to form. https://arxiv.org/abs/2210.02420

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