This video is part of my continuing coverage of the Trappist
- 1 system. This star system is known to harbor at least 7 roughly earth-sized
planets, and may hold the potential for liquid water on at least one of them.
For the back story on this system, see my previous videos on this channel.
Much new information has come to light about this system, so
much so that I'm barely able to keep up with the veritable snowstorm of
scientific papers that have been coming out. One thing that hasn't changed
about this system though are the uncertainties surrounding it, and it will be a
while before any sort of consensus can be made on what these worlds are really
like.
One of the main uncertainties involved with Trappist - 1 was
the role of the outermost seventh planet and how it relates to the inner
planets and the orbital stability of the system as a whole. This is because in
the initial observations that planet had only been observed to transit once in
front of the star.
But, in a paper from March 12, Rodrigo Luger and colleagues
report further observations done with the Kepler space telescope that have
narrowed down this planet's orbit and suggest that Trappist - 1h, which is
thought to be larger than Mars but smaller than earth, could harbor liquid
water with the right atmosphere, which would be some mix of hydrogen, nitrogen and
carbon dioxide and could thusly be habitable.
But that's a could be, as with most of the planets in this
system. A big factor here is stability, and that's a question that's in flux. Planets
without stable orbits aren't conducive to life, especially if they occasionally
ram into each other. So, while it's not yet known just how stable this system
is, it seems to be moving into more stable territory. A paper from this morning
by E.V. Quintana and colleagues suggests that the presence and characteristics
of the seventh planet actually serves to help stabilize the system according to
their models.
Another issue that's recently come to light that affects the
habitability of the Trappist planets comes from a paper by Peter Wheately and
colleagues, links to all papers in the description below. They suggest that the
environment that the Trappist planets orbit in would be one with very, very
high ultraviolet radiation streaming from the star. UV does not favor life as
we know it, and would put some constraints on what sorts of atmospheres these
planets can have.
And there's a further problem, according to a paper by K.
Vida and colleagues, the Trappist -1 star displays frequent solar flares. This
could mean that the atmospheres of these planets, if they have them at all, are
continuously altered by the star's actvity. That too disfavors life.
On the opposite side of things, another big hurdle as far as
the potential for life at Trappist -1 was the age of this star system. The Luger
and colleagues paper however lays out indications from the star itself that the
system is actually significantly older than originally thought with an age of between
3 and 8 billion years. This favors the potential for life, our own sun is in
that age range at 4.6 billion years-old and that's proven to be enough time to
produce an advanced civilization.
Civilizations are always unlikely and there is no indication
whatsoever of one being at Trappist -1. But it was still worth it for SETI to
take a look, however. Using the Allen Telescope Array, Seth Shostak and his
colleagues searched for radio signals emanating from this system and the
surrounding area. They found nothing. But that doesn't close the door for life
in general, and indeed, the lack of good atmospheres might not either.
These planets orbit very close to their star, in fact they
all orbit Trappist - 1 closer than Mercury orbits our sun. They also are very
close to each other, a routine sight on one of these worlds would be another
planet passing by appearing larger than our moon does in our sky. This would
create tidal heating and perhaps subsurface oceans in the grain of Europa might
be possible.
Another thing about this system that stands out is that
because these worlds are so close to each other, they would be prime territory
for panspermia, meaning that if one planet evolved life it could have easily
been seeded to the other planets and vice versa. Multiple abodes favor life
long-term.
So what of future studies of these planets? With the advent
of the James Webb Space Telescope on the horizon along with European Extremely
Large Telescope, we should soon have the ability to study the atmospheres of
these planets in some detail. As noted in a paper by O'Malley-James and
Kaltenegger, scientists will want to look for gases like ozone, if you see that
one then the ultraviolet light equation changes significantly and indeed, that
would be a strong indicator of life.
And, as a note for the curious, the original team
investigating this world were mainly Belgian. Belgium
is famous for it's many beers and Trappist is perhaps the most famous of them
leading some to wonder if this system was in fact named after a beer. As it
turns out, technically no.
It's named after the TRAPPIST telescope at La Silla
observatory in Chile ,
though the team is said to have toasted the discovery with said beer. But don't
feel let down, the telescope itself is named after the beer. It is a backronym to
highlight the Belgian origin of the project, and rumor has it that the planets
themselves are all informally nicknamed by the team after various other Belgian
beers.
Thanks for listening! I am futurist and science fiction
author John Michael Godier and I would like to officially announce the launch
of my second channel! It's called John Michael Godier II, how's that for
imaginative youtube channel names, link in the description below. It's dedicated
to science fiction and the science behind it and I have already uploaded a
sampling of content to explore and be sure to check out my books at your
favorite online book retailer and subscribe to my channel for regular, in-depth
explorations into the interesting, weird and unknown aspects of this amazing
universe in which we live
No comments:
Post a Comment