Colloquia

They Came from Outer Space: Comets, Unseen Planets, and 'Oumuamua'

Wed 4 Dec 2019
Location:

Space Telescope Science Institute (STScI)
3700 San Martin Drive
Baltimore, MD 21218

Time:

2:45 PM - 4:00 PM

Contact Information:

Have questions? Please contact Kailash Sahu.

Description:

Speaker: Scott Tremaine (IAS, Princeton University)

Comets have inspired awe since prehistoric times, but the modern study of comets only began with Halley's successful prediction of the return of what is now called Halley's comet.  Even today there are only a few thousand comets with well-determined orbits. Nevertheless, the analysis of these orbits yields a compelling model for the formation, evolution and present distribution of comets. This model implies that there are two distinct sources of comets: the Oort cloud, containing over 100 billion comets at 5,000 to 50,000 times the Earth-Sun distance; and the Kuiper belt outside Neptune's orbit. I will review our current understanding of the formation of the Oort cloud and Kuiper belt, and what they can tell us about possible undiscovered planets beyond Neptune. I'll also describe some of the puzzles arising from the recent discovery of the interstellar asteroid/comet 'Oumuamua.'

Notes:

All talks are held on Wednesdays in the STScI John N. Bahcall Auditorium at 3:00 p.m. preceded by tea at 2:45 p.m.

Please direct questions or comments to the contact above. The 2019-20 committee members are Paule Sonnentrucker (STScI Chair), Annalisa Calamida (STScI), Will Fischer (STScI), Ethan Vishniac (JHU Co-chair), Kevin Schlaufman (JHU), and Graeme Addison (JHU).