September 19, 2018, 3:30 p.m.
Building 3, Goett Auditorium
UNIVERSITY OF HAWAII
The First Interstellar Comet"
The Pan-STARRS1 telescope, located at the summit of Haleakala on
Maui, is tasked with finding Near Earth Objects (NEOs) that may
one day pose a hazard to Earth. On October 19, 2017, a fast
moving object was discovered, which by October 30 had an orbital
eccentricity of 1.196 ± 0.006 making it -- now designated
1I/2017 U1 (`Oumuamua) -- the first asteroid or comet of
interstellar origin. In the following weeks, we began an intense
follow-up campaign before it faded from view to characterize
`Oumuamua and the possible nature of its violent ejection from
its home planetary system. Its red colored lightcurve had a 7.34
hour period, implying it has a highly elongated shape, about 800
x 80 x 80 meters. From the largest ground-based telescopes, it
showed no cometary activity, but later Hubble Space Telescope
data showed it has a non-gravitational component of its motion
implying it is in fact a comet, but one with dust production
very different from anything else in our own solar system.
About the Speaker:
Robert Weyrk completed his Ph.D. at the University
of Western Ontario in London Ontario with Peter Brown, where he
made simultaneous radar and video measurements of meteors in
order to better constrain mass estimates of meteoroids. He did a
short postdoc after that with Bob Hawkes at Mount Allison
University in Sackville New Brunswick where he worked on
meteoroid ablation modelling. Following this, he moved to Hawaii
to work with Richard Wainscoat and the Pan-STARRS survey to find
much larger asteroids and comets, with a focus on Near Earth
Objects (NEOs). He has been there for 3.5 years.
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