On October 19, 2017 at the Haleakala Observatory in Hawaii, human beings detected the first-ever visitor from interstellar space: an object from outside
our own solar system. A pair of Harvard
scientists say a massive, fast-moving visitor to our solar system may have been a probe sent by an advanced alien civilization. It's an alien spacecraft. Some sort of alien technology, perhaps exploring the cosmos. It's called Oumuamua, which roughly translates
as messenger from the past reaching out to us in Hawaiian. Everything in our solar
system is on a closed loop. You know, some orbits are nearly circular, some are elongated. This one was an open-ended orbit, which means it's coming from
outside the solar system. Then something even more strange happened. Upon leaving the inner solar system, astronomers reported an
unexpected acceleration, only adding to the
hypothesis that Oumuamua was some sort of alien creation. It would be exciting to think
this is an alien spacecraft. You know, one of the burning
questions on many minds is: Are we alone? But you have to be responsible about it. And if there is a perfectly
common explanation, you shouldn't go to
the exotic explanation. After observing the object, most astronomers agree
that it's probably a comet. Like 2I/Borisov, the other interstellar
object seen a year later. But we may never know for sure. Things that come in on these type of very elongated orbits move really fast when they're close to the sun, and then they're much
slower as they move out of the solar system. So when you looked at the
brightness of this object, it was going to only be easy
to observe for about a week. In that short window of time with just a pinpoint of light, scientists were able to make
guesses on the object's shape, its size, how fast it was
spinning and its color, which is thought to be reddish. But there are a lot of
questions about Oumuamua and space that'll remain unanswered unless we're able to act more quickly. Right now, many of the teams are saying we need the capability to have reactive missions, fast missions that can
respond to a discovery. Because right now, the missions, the way NASA works with
the small missions, is you put in a proposal
and it takes many years to get that approved. And then it might be a
decade between proposal and actually launching a mission. And obviously for Oumuamua, that would have been pointless. So we would like to have
missions that are maybe ready to go, built and in orbit, waiting for a new discovery or something that could
be launched immediately. That's why teams of scientists are planning missions to
wait for objects in space, and spring into action as soon as something interesting is detected. It may be humanity's only
chance to see an object from another solar system up close. The space between solar systems is huge. Unless warp drives become a reality, traveling from one to
another any time soon is probably not possible. Well, I mean, I'm a "Star Trek" fan, and according to "Star Trek" in 2063, I think, Zefram Cochrane
invents the warp drive. Zefram Cochrane? Of Alpha Centuri? The discoverer of the space warp? That's right captain. So if that happens, definitely. If not, I think it's quite difficult to reach anything within my lifetime. Currently, the only
way that we have to see some of the material from
these other star systems is stuff that is in interstellar
space that gets to us. Although we've never gone near an interstellar object, we've learned a lot
from approaching objects from within our solar system. In 2014, the European Space
Agency's Rosetta probe rendezvoused with Comet 67P. Rosetta is the first mission that ever delivered a lander
to the surface of a comet. This had never been done before. It's the first mission
that went into orbit around a comet, and it accompanied it
for two years and a bit, from 2014 to 2016. And from this mission, the
European Space Agency made a lot of interesting observations. I think this shape was
one of the major surprises that we had at the beginning. No one really expected that. Another really big
discovery, I think, was that the water that came off Comet 67P is not that kind of water
that we have on Earth. And if it's not the same, you know that they're probably not from the same source. So I think this was quite unexpected because people really thought this comet could be a real possibility to bring water to Earth. Scientists are still looking at the data from the Rosetta mission and making exciting new
discoveries about 67P. And those discoveries in turn give us hints about the early
days of our solar system. I think comets are very interesting because they can actually
tell us where we come from. The comets are always thought as kind of leftovers from the solar-system formation. And if we explore comets, we can understand how
the solar system formed, how Earth formed and basically how humans in the end came to be because without Earth we wouldn't be here. While the Rosetta mission was a success, Comet 67P orbits the sun every seven years and is affected by the heat, losing gases and changing its
composition with each orbit. Scientists at ESA recognized
the need to study a comet with a pristine surface, one that's never been near the sun, and that's largely unchanged since the formation of our solar system. This is known as a new comet. They were talking about this problem of pristine surface
versus changed surface. And they said, "Well, you
know what we should do? We should try and get to
one of those new comets." And so the Comet
Interceptor idea was born. This is very different
from previous missions that we've done where
we've always gone to comets that go round and round
in the solar system. And the reason why we go to these is that we know where they are. We can observe them and then get their position very accurately. But Comet Interceptor
doesn't want to do that. Comet Interceptor wants
to go to a very new comet and observe it with three
different little spacecraft: one mother spacecraft, as we call it, and two sub-spacecraft. And we want to basically
observe everything we can. We'll take pictures of
the comet's nucleus, which is a little thing in the middle. We'll take pictures of
the gases around it, the dust that comes off
of it, the environment. Interstellar objects are not Comet Interceptor's
primary target. Since we've only ever detected two, we don't know when or if
we'll detect another one. This mission is mainly going after unknown new comets from beyond
Neptune in the Oort cloud. This is the spherical, outer
part of the solar system and is believed to contain
trillions of comets. The majority have never
entered the inner solar system. But every once in a while, one of these icy bodies
gets a gravitational bump from another object, flinging it into the inner solar system. And Comet Interceptor hopes
to be ready for the next one. And there is another very
interesting target family, let's say, which is interstellar objects. So if there is an interstellar object like Oumuamua or Borisov, that's obviously where we we will be going because that's by far the
most interesting thing that we can explore. And Comet Interceptor is the only mission that has the capability to explore such an interstellar object. But to catch up to a new comet from our solar system or
an interstellar object, they needed to come up with a way to deal with the short lead time, something that's never been done before. The problem is that these dynamically new
comets are usually detected just a couple months before
they get close to Earth. And a couple months as everyone involved in any space mission knows is not enough to build a spacecraft and go somewhere with it. So we're actually more looking
at a timeframe of five years for the mission, where we have
five years of waiting time and we can choose whenever
we detect a suitable comet. And we think that the chance of detecting a suitable, dynamically new comet that we can reach is over
90% over these five years. To be able to wait for
a comet out in space for up to five years,
they'll send a small probe to the Earth-Sun Lagrange point, a place where the gravitational pull from both bodies cancel each other out, creating a stable orbit. And when Comet Interceptor gets there, it will just wait for five years. And once we detect the comet we'll be setting off towards rendezvous point, and this will be done
with chemical propulsion. Data gathered by the interceptor could be compared to other comet missions, so scientists will be able
to predict the effects of the sun on comets, giving them clues as to what the formation of our solar system was like, and in turn teach us about
how Earth came to be. It is a very ambitious mission. That's, I think, why it's so exciting. I mean, if you just do
things that are easy, it's a bit boring. So this mission is very
difficult to pull off. And I think that the team here at ESA
has done a very good job in kind of reminding everyone of the constraints of the mission while still getting the
best science out of it that we can expect at the end. Although not as far along as ESA's Comet Interceptor, which is set to launch in 2029, there is a team at MIT in
its initial planning stages, designing a mission specifically targeting interstellar objects. We see interstellar objects as the new frontier in planetary sciences. And now that we detected them, it really opens up the door of like, oh, what new things can we discover? And how do these new discoveries frame our thinking about the
formation of this star system and other star systems? So it's really science in a nutshell. Their proposal is called Dynamic Orbital Slingshot for Rendezvous with Interstellar Objects. Much like the Comet Interceptor, it will wait in space
and spring into action at the right time. So the unique part about our concept is that using the solar sail, our payload remains stationary. We can completely cancel
out this force of gravity. Of course, the materials that are required for this are exotic. Some of the materials are
currently being developed at academic labs. So we think it's within
the realm of possibility for a future mission to
do something like this. We can lay in wait, watch our local space for
any interstellar objects that might be entering that space and then spring to action
and get a close-up view of that interstellar object. Once an object is detected, it would be allowed to leverage
the gravitational force of the sun in a free-fall trajectory towards the detected
object, matching its path. The team received phase-one
funding from NASA, which gives them nine months to come up with a solid plan before
applying for the next phases. We're optimistic about phase two and we hope to find to
eventually get to a phase three. And if we're able to get there, then this technology becomes
closer to becoming reality. And both of these missions are coming at a good time. Telescopes that are coming
online in the next few years will be able to detect
more pristine comets and interstellar objects than ever before. Large synoptic survey telescope, the Rubin Observatory, is being built in Chile and that's going to be much bigger. And scientists are predicting we might start to see one of these each year once that is built,
because it goes much fainter. Why is it important to
study objects like this? Well, I think Oumuamua and
other interstellar objects are really important because
they are the likely leftovers of building planets in
another solar system. And right now, we don't
have the sensitivity or resolution to really
watch that process unfold. You know, for example,
are all solar systems chemically the same? Is it
the same physical processes that build planets? 'Cause this is important for
the question of, are we alone? And so some of the ways
to answer those questions require detailed chemical compositional makeup, which you can't do remotely. I think we should be interested
in interstellar objects because it really tells us something about our own history, whether or not our star system is unique or is our star system similar
to other star systems? And if we find out maybe some compositions of the material around other star systems, it could inform us what's out there. If we can explore an interstellar object, we can explore by proxy another solar system. And that's something really exciting because we know there's so
many other solar systems with exoplanets and with maybe even exoplanets that
are kind of like Earth. And understanding those systems better I think is really interesting.
Really amazing video! I recommend watching the other Bloomberg Quicktake 'Moonshot' episodes as well.
What do they mean when they say the water on the comet is not the same as water on Earth?
Quite an incredible object, caused kind of a morality panic on this board with people absolutely dedicated to the fact that it had to be a completely unremarkable comet or asteroid, when in reality it was so revolutionary and strange that a new classification, U was created for it.
I hope more of these remarkable objects are detected so we can get to the bottom of its non-gravitational acceleration, which is still hotly debated and a wonderful scientific mystery.
Check out these podcasts about it
https://overcast.fm/+NJ4JA0yZE
https://overcast.fm/+eZyAFuMjA
It is a lost starship that could be even related to our origins.