I know, I know, this is getting comically hilarious.
Aliens, next episode.
Although maybe, aliens this episode?
Anyway, NASA made a huge announcement today, and I thought it was important enough to stop
everything we were doing, call Chad and Karla back to Universe Today headquarters to help
me cover it.
Here’s the announcement: NASA announced today that they’ve found an important chemical
for life - hydrogen gas - blasting out of Saturn’s icy moon Enceladus.
In addition to this, they confirmed that Jupiter’s Europa has icy geysers too.
We’ve known about Enceladus’ plumes for a while, so the discovery of hydrogen gas
is pretty exciting.
We’ve suspected Europa has jets, but more confirmation of their existence is great.
We don’t know if there’s hydrogen gas in Europa’s plumes… yet, but there’s
a spacecraft in the works to help us find out.
Let’s get into the details.
Earlier this week, NASA teased us that they were going to be announcing something interesting
about the ocean worlds of the Solar System.
They were vague on details, but Mike Brown confirmed what I’d always expected: Europan
Space Whales.
I was all ready to hear their mournful songs, muffled by kilometers of ice, but I was sadly
disappointed.
Okay fine, the reality turned out to be pretty cool too.
NASA announced that they’ve found evidence that there’s hydrogen gas pouring into the
water of one of Saturn’s icy moons: Enceladus.
The source of this hydrogen is probably some kind of hydrothermal activity down beneath
the ocean.
The tidal interactions between Enceladus and Saturn heat up the moon, giving it vast oceans,
which spews water into space from cracks at its southern pole.
Here on Earth, remember, wherever we find water, we find life.
And one really interesting place that we find life is surrounding volcanic hydrothermal
vents at the bottom of the ocean.
These volcanic vents belch plumes of material into the ocean, and serve as the energy source
for a vast array of lifeforms.
Heat loving thermophilic bacteria known as methanogens absorb the hydrogen coming from
these vents and use them as an energy source.
Other creatures eat this bacteria, and you’ve got a thriving ecosystem and food chain.
One of the most interesting things about these hydrothermal vents is how they provide a completely
separate ecosystem from the rest of life on Earth.
They couldn’t care one bit if the Sun disappeared tomorrow, and all life died.
They’d keep slurping up their hydrogen gas, going and going.
And that’s why this discovery about Enceladus is so exciting.
In their announcement, planetary scientists working with Cassini described how the spacecraft
detected this hydrogen gas in the plumes blasting out of Enceladus.
On October 28, 2015, the spacecraft made its deepest dive through the plumes coming out
of Enceladus.
It sampled the icy material and found that 98% of the plumes is water, 1% is hydrogen,
and the rest is a mixture of ammonia, methane and carbon dioxide.
Cassini isn’t equipped to search for life.
It just doesn’t have the instruments on board.
Its Ion and Neutral Mass Spectrometer instrument did the next best thing.
It found food for bacteria.
When this environment is found on Earth, bacteria has a feeding frenzy.
That’s pretty exciting.
The discovery over on Europa is different.
Astronomers had suspected there were plumes on Europa like Enceladus, based on images
taken by the Hubble Space Telescope back in 2014.
But the results were inconclusive.
The Hubble team took a second round of images in 2016, and detected plumes coming from the
same region of Europa, confirming their existence.
Is there hydrogen gas in those plumes too?
We have no idea yet, but we soon will.
In a second, I’m going to explain what we’re going to do about this.
What plans are in place to study this even further, but first I’d like to thank Khaled
Al Tal, Isaac Arthur, Lee Stuurmans, Larry Johnson, Ryan Williams, and the rest of our
705 patrons for their generous support.
If you love what we’re doing and want to help out, head over to patreon.com/universetoday.
Now we see another tantalizing clue that there could be life in the oceans of Europa and
Enceladus, what are we doing to do about it?
What plans are in place to go back and study these worlds up close?
Good news!
NASA has actually been working on a new spacecraft that will be able to answer our questions.
It’s called the Europa Clipper, and if all goes well, it’ll launch for Europa in 2022
on board the new Space Launch System, or SLS.
This mighty rocket will only take 3 years to reach Jupiter.
It won’t actually orbit Europa, since the radiation from Jupiter would kill even a hardened
spacecraft.
Instead, it’ll sweep in and make at least 45 flybys of the moon over the course of its
mission, building up a detailed map of the entire world.
Some of its flybys will be as close as 25 km, and will pass right through the plumes,
tasting them with an even more sophisticated suite of instruments than Cassini.
If hydrogen gas is coming out of Europa too, the Clipper will detect it.
One of most interesting and controversial instruments will be its ground penetrating
radar system.
Controversial because this instrument will consume a lot of the spacecraft’s energy
budget, which could have been used for other instruments.
Exciting because it’ll be able to determine the thickness of the icy shell on Europa,
and give us a sense of just how big these oceans are.
There could be pockets of liquid water closer to the surface.
In addition to the spacecraft itself, the Europa Clipper might be equipped with an additional
tiny lander.
After the spacecraft had mapped enough of the surface, NASA planetary geologists could
identify the best landing site to visit.
Imagine a lander touching down near the vents, sampling them up close.
So much science.
Once again, we still don’t know if there’s actually life on Enceladus or Europa, but
this announcement is a huge step forward.
It tells us that there’s food for life down there, under the ice.
And now we just have to go back and learn more.
What do you think?
Are you excited by this announcement?
Do you think this changes our priorities for exploration of the Solar System?
I’d love to know your thoughts in the comments.
Next time, it’s that UFOs episode I keep talking about, which is already shot and in
editing.
And unless there’s some really exciting episode, you’ll finally get to see it.
Promise?
Europa would be cool, and so would Enceladus, but you know where I really think we should
go?
Titan.
Here’s an episode all about what kinds of missions we could send to Titan.