Name: This Image Might Show Exomoons Forming! | SciShow News
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Every now and then, astronomers give us an image of space

And another one of those images was published

last week in the Astrophysical Journal Letters.

This is an image of a star about 370 light-years away.

See that little spot on the right edge of the disk?

conclusively imaged before: a circumplanetary disk.

This is the cloud of stuff that the planet is

pulling from in order to grow, and someday,

if it hasn't already, the leftover material in it

trillions of kilometers away is mind-blowing,

It's about 5 million years young, and it has

the second of which was announced just last month.

The first planet we found orbits about as far away

second planet is about where Neptune would be.

It's called PDS 70 c, and it's the planet

Initially, though, scientists weren't just focusing on this world.

Instead, they were trying to study both planets,

along with the disk of stuff they formed from.

To do that, they re-analyzed some data taken by

a suite of Chilean telescopes called ALMA.

And the signal was brighter than astronomers expected.

Combining that observation with both optical

and infrared data from other telescopes, the team concluded

there must be a circumplanetary disk around PDS 70 c.

Now, although this image does look pretty clear,

it's important to know that it doesn't actually show the disk itself.

so this picture just shows the general region around it.

But astronomers are really good at pulling information

out of smudgy images, which is why they're so confident

and why they can say they've conclusively imaged it.

partly because it can teach us about the planet.

For example, using some assumptions based on

astronomers were able to estimate the amount of dust in the disk.

It's between 0.2 and 0.4 percent the mass of Earth.

Also, one data point suggests that hydrogen gas

is still falling from the disk onto the planet,

Because some of that disk material won't join the planet:

If it hasn't already, it'll clump together into a multi-moon system,

like those we see around Jupiter and the other gas giants.

but we could also get a small spherical body or two.

There's a lot to unpack here, but one of the best parts

is that this image isn't only important for

Because, maybe surprisingly, this isn't something we totally understand yet.

Collecting more data about PDS 70 c will help teach us

how gas and dust collect around large planets in their early years,

and how circumplanetary disks interact with the disks around stars.

This information might even help us understand our own solar system,

since we have some big gas giants of our own.

Speaking of, not all astronomers are studying Jupiter-like planets:

Some researchers are studying the real deal.

why our solar system looks the way it does.

But also, studying this planet is cool in its own right.

the world learned something new about its auroras.

According to a new study, these light shows

Jupiter is the fastest-spinning planet in our solar system,

making one rotation about every ten Earth hours.

That means its magnetic field rotates really fast,

and it generates a force that actually steals

charged sulfur compounds off of its closest spherical moon, Io.

When charged particles move, they generate a current.

And this electric current is kind of a big deal on Jupiter.

It directs electrons toward the planet's upper atmosphere,

atmospheric particles and make a pretty UV aurora.

Generally speaking, this is about the same way

auroras form here on Earth, although our charged particles

come mostly from the Sun and not from the Moon.

But it turns out that the electric currents around Jupiter