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We might be sitting next to the largest bomb in the galaxy and NASA's InSight lander will touch down on Mars this Monday!

Host: Hank Green

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[ ♪ Intro ].

I don’t want to alarm you, but we might be sitting near the largest bomb in the galaxy. It’s a star just 8000 light-years away, and when it explodes, it could release more energy in seconds than the Sun will emit in its entire lifetime.

Fortunately, it doesn’t seem to be pointed at us. We think. An international team of researchers announced this star’s discovery on Monday in the journal Nature Astronomy.

It’s part of a binary star system surrounded by a cloud of dust, which scientists are calling Apep after the ancient Egyptian god of chaos. But the system’s official name is… honestly, it’s the most complicated name I’ve ever seen. So thanks for the snappier name, astronomers!

Apep as a whole is pretty interesting, but it’s the brighter of the two stars that’s the big deal. It has astronomers excited because when it explodes, it may release what’s called a gamma-ray burst. Gamma rays are the most energetic form of light, and gamma ray bursts are some of the universe’s most powerful events.

They’ve been observed in other galaxies since the 1960s, but never here in the Milky Way. Bursts seem to happen when large stars die under certain conditions, and this new star in Apep seems to fit the bill. This object is an example of a Wolf–Rayet star.

They occur when certain massive stars, called O-types, run out of hydrogen fuel and begin to burn heavier elements. Those elements release more energy, which takes the form of a wind that blows away the star’s outer layers. Then, the object’s exposed core is left behind.

The star in the Apep system has winds blowing at some 12 million kilometers per hour, or about 1% the speed of light. But what’s unusual is that the dust surrounding the star is moving more slowly. Almost ten times slower.

Usually, the two move at about the same speed because the wind pushes the dust along too. In the paper, the authors consider a bunch of reasons why this might be happening in the Apep system, but only one really makes sense. If the star is spinning at nearly the speed necessary to break it apart and is interacting with winds from a second, slower star, an uneven wind pattern could occur.

This could explain the dust’s unusual motion. And that rapid rotation is also the condition needed to form a gamma-ray burst when this thing finally explodes. Thankfully, when that happens, it probably won’t affect us.

From what scientists can tell, these bursts tend to shoot out along a star’s rotational axis, and this star is not pointed our way. If it was, it’s hard to know for sure what would happen, but it probably wouldn’t be great. The gamma rays would likely destroy much of the ozone in Earth’s upper atmosphere, which protects us from the Sun’s harmful ultraviolet light.

Without that protection, DNA could mutate much more often, which wouldn’t be good for things like cancer rates. So let’s just say we’re glad Apep is pointed the wrong way. It’s amazing that we can be effected by something eight thousand light years away!

But in even happier news, we’re about to get a new spacecraft on Mars! Six and a half months after launching, NASA’s InSight lander is scheduled to touch down on the Red Planet Monday, November 26th. If all goes well, it will land on Elysium Planitia, which is, wait for it, possibly the most boring place on Mars.

But before you get your pitchforks out and start like, hunting NASA people, there’s a really good reason why they sent an $800 million dollar lander to one of the solar

system’s least interesting places. InSight’s mission is to study the interior of Mars, so it doesn’t really matter what’s going on at the surface. Therefore, scientists and engineers chose a place to land where all the non-science stuff would be as simple as possible.

InSight will land near the equator, where there’s plenty of solar power, at a spot that’s level and debris-free. The site is also low in elevation, which will give the spacecraft plenty of time to slow down during its descent, and NASA thinks the soil is soft enough to make drilling easy. InSight will enter the atmosphere around 3 PM Eastern Time and use its combination of a heat shield and parachute to slow down in the thin Martian air.

Once it’s nearly on the surface, twelve small rockets will fire, slowing it down for a gentle, precise landing. Then, the spacecraft will use its two-year mission to carry out two big tasks.

One: it will hammer a probe several meters into the surface to measure the heat flowing out of the planet. And two: will also use a seismometer to listen for Marsquakes, earthquakes on Mars. Together, these experiments will help scientists understand what’s going on inside the planet and how those processes are different than those found on Earth. Much of InSight’s landing system is borrowed from 2007’s Phoenix Mars Lander, with one big addition.

The lander is joined in space by MarCO, a pair of briefcase-sized cubesats that have been traveling alongside InSight since launch. During the six-minute landing, they’ll act as a communication relay, sending critical data back to Earth. If InSight crashes, MarCO will be the main reason we’ll know why.

But the cubesats’ real mission is to prove that such tiny spacecraft can survive interplanetary space and carry out useful tasks. If they succeed, they could usher in a new era of space exploration that will make the cost of exploring the solar system way lower. It’s not, like, a giant space bomb or anything, but it is still pretty exciting stuff.

Thanks for watching this episode of SciShow Space News! If you want to keep up with the latest discoveries happening in space, like landing on Mars, which I am very excited about, you can go to to subscribe. [ ♪ Outro ].