[Music throughout] My name is
Karl Battams, I’m a computational scientist at the Naval Research Lab, and for nearly 17 years
I’ve been in charge of NASA’s Sungrazer Project. The Sungrazer Project is
a citizen science project that allows anyone in the world to discover new comets
that are seen in images recorded by the joint ESA/NASA SOHO satellite.
Recently, the project has reached a very special milestone:
SOHO has found 4000 previously unknown comets in nearly
25 years. So I want to share with you my favorite comets
that SOHO has discovered. [#4 Twin Comets] These were a pair of bright comets,
both members of what’s known as the Kreutz group, which is a very large
family of comets that all follow the same path in space.
Unfortunately, and like nearly all of SOHO’s comets, these guys were completely
vaporized by the Sun’s radiation. [#3 SOHO 422] Most of
SOHO’s comets are what we call sungrazers, which means they follow an orbit that almost
grazes the surface of the Sun. But we’ve also discovered a lot of comets
that stay just a bit further away from the Sun, and, unlike sungrazers,
manage to at least partially survive passing by the Sun. This comet,
SOHO’s 422nd discovery, was found back in
2002. Here we see it swinging around the sun at a seemingly safe
distance. Unfortunately, it kind of looks to me like this comet may
have turned entirely to dust towards the end of the movie.
It can be hard to know the exact fates of comets like this because
they’re often impossible to locate from Earth because they’re so close to the Sun.
[#2 C2015 D1] One of the great things about SOHO’s comet discoveries
is they also teach us things about the Sun. Here we see what looks like a
typical bright sungrazer racing through the LASCO cameras and in this case disappearing
behind LASCO’s solar occulting disk. And normally this is
the last we see of them. But this comet, to our absolute astonishment,
was also visible in images recorded by NASA’s
Solar Dynamics Observatory, which looks at the Sun’s million-degree atmosphere
in extreme ultraviolet light. This was the first time anyone had ever
seen something like this. We were completely blown away by this result. And
we can use comets like this almost like remote probes. They
allow us to learn about the environment close to the Sun
by watching how the comet is reacting within that
really extreme environment. [#1 The 4,000th] Finally, this is certainly not
the biggest or brightest comet SOHO has ever found, but for me it’s
absolutely one of the most important. This is SOHO’s 4000th
comet discovery. That’s a truly remarkable milestone for this mission to reach.
Particularly as it was never designed to look at
or discover comets. This milestone is also a huge testament to
the NASA and ESA scientists and engineers in support
teams that have kept SOHO running so well all these years.
And of course, probably most of all, it’s a testament to the
army of citizen scientists who have contributed so much
free time to scouring the SOHO images and
helping us realize all of this incredible science that we’ve gained so far.
Here’s hoping for another 4000 comets.
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