Last week, NASA released the first full-frame image from its newest
planet-hunting spacecraft and astronomers have already used it to
detect two brand-new extrasolar planets. Welcome back to Launch Pad, I'm Christian
Ready, your friendly neighborhood astronomer. In my previous video I talked
about the Transiting Exoplanet Survey Satellite, or TESS. NASA released the
very first full frame image, but flying in under the radar were three new papers
submitted by three teams of astronomers announcing the discovery of TESS' first
two exoplanets. Now it's very important to remember that the papers that have
been submitted are what are called 'pre- prints'. In other words, they have not yet
been vetted by peer review or the editors of the journals they've been
submitted to. So with those caveats out of the way, let's talk about what they
found out. Now TESS uses the transit method to detect planets around other
stars. That means it watches for a repeating drop-off of light caused by a
planet making a regular periodic orbit around the star. Not only that, but the
larger the drop-off in light, the larger the planet must be. So astronomers can
measure things such as a planet's orbital period, its distance from its
host star, and even its radius. The first planet was discovered around the star
pi Mensa. This star is already known to host one planet called pi Mensae b. Pi
Men b is a super Jupiter that takes about 5.7 years on a very
elliptical orbit to go around its star. But this new planet, pi Men c, is a
very different kind of animal. It orbits its host star once every 6.3 days!
Yeah, its year is less than one of our weeks! But in order to have such a
short orbital period, pi Men c has to orbit at a distance of just 0.07
astronomical units. That's about seven percent the distance from the Earth to
the Sun. So yeah, New Year's parties every week or so, not
bad, right? But the second planet that was discovered is even stranger than pi
Mensa c. LHS 3844 B orbits around a red dwarf star. That is it's a star that is
smaller and cooler than our Sun. However, LHS 3844 b's period is
only 11 hours! That's it's year. That puts this particular planet at something like
0.006 astronomical units or 1/6000th
the distance from the Earth to the Sun. Crazy, right? Now both of these planets
are larger than Earth and they're presumed to be rocky planets, although we
really can't tell this for sure just by looking at the light curve data.
Nevertheless, it's widely suspected that these two planets fall into the so-called
'super Earth' category. They're a little bit larger than Earth and
probably not gaseous giants like Neptune or Saturn. To really know more about
these planets, we need to follow-up with larger ground-based telescopes or the
James Webb Space Telescope to study their atmospheres. Assuming, of course
they even have atmospheres to study. pi Men c has an estimated surface
temperature of over 1100 Kelvin. Because LHS 3844 b orbits a red dwarf sta,r it's
merely 800 Kelvin. Still, that's probably going to be plenty hot enough to have
stripped away any atmospheres that these planets may once have had. It's also
likely that these planets are tidally locked to their stars. That means the
daytime sides that these planets are in constant daylight and are being blasted
by the scorching heat of their host stars. Their far sides, on the other
hand, are probably plunged into perpetual darkness. By the way, Perpetual Darkness
was the name of my progressive metal band in college. So the possibilities
that life could exist on either of these two worlds are probably next to zero, but
we won't know for sure until we can do some follow-up studies with the James
Webb Space Telescope or the upcoming super telescopes on the ground. After all,
all we can really learn about these planets right now are just their orbital
distances, their are periods around their stars, and their sizes, well from there we
can calculate things like their effective surface temperatures, but
that's about it. Now because TESS only spends 27 days observing a single sector,
it's going to be sensitive to these really short period planets. At least at
first. However, over time it will become
possible to detect longer period planets because the fields that are near the
ecliptic poles will overlap with one another, allowing more observation time.
If TESS gets an extended mission, it could even observe both of these
hemispheres for a lot longer. Now there's no way I'll be able to report on every
single planet TESS discovers, but TESS has only been at it for about a month
before it bagged its first two planets! There's going to be a lot of really cool,
strange new worlds coming down the pike. Now if you haven't seen my video already
about TESS, you definitely want to check that out so you can learn more about the
TESS mission. And if you'd like to learn more about how astronomers detect
planets around other stars, feel free to check out a video that I've done on that
as well. I'll have links of them here and in the description below. So what do you
think about these first announcements? Let me know in the comments below and
I'll be sure to check it out. And if you'd like to join me on this journey
through this amazing universe of ours, well please make sure to subscribe and
ring that notification bell so that you don't miss out on any new videos. Until
next time, keep watching the skies.
this thing right...?
This planet orbits the star LHS 3844 [BEEP]