On a space mission to Proxima Centauri B

This is considered an important condition for life. But it is still too early to predict this. We don’t even know if this exoplanet has an atmosphere that can hold liquid water and is suitable for life. In fact, we have never seen Proxima Centauri b. What’s up with that?

Proxima Centauri B remains under the radar

Using ultra-powerful space telescopes like the James Webb and Euclid, we can see stars billions of light-years away. However, observing exoplanets orbiting these stars is not always easy, Lichtenberg explains. “This is because these planets are relatively much smaller and emit much less light.”

Exoplanets are generally not glowing fireballs. That’s why a planet like Proxima Centauri B, which is only 4.2 light-years away, still manages to stay out of the spotlight. But how do we know that this planet exists?

How do you discover an exoplanet?

“There are two ways to determine the presence of an exoplanet,” Lichtenberg says. “The first is a method of measuring transitional light.” You might forget that name right away, but what it boils down to is that we’re trying to detect an exoplanet by looking closely at the star for a long time. “When there is a decrease in starlight, we know that an exoplanet is passing in front of the star.”

One problem: “This method only works if the exoplanet lies exactly on the line between Earth and the star at some point in its orbit.” Otherwise there would be no eclipse visible to us. And you guessed it: Proxima Centauri B doesn’t. Therefore, we defined the existence of an exoplanet in a different way.

The dance of stars and exoplanets

There’s something special happening with the Proxima Centauri system. Because the star is much smaller than our Sun, and Proxima Centauri B is relatively close to it, not only does the star’s gravity pull on the exoplanet it orbits, but the exoplanet’s gravity also has a noticeable effect on the star, Lichtenberg explains.

As a result, the star is not exactly at the center of the system, but is oscillating with the orbit of its planet. “By looking at the anomalies in the star’s motion, we can conclude that there is likely a large exoplanet nearby. This is Proxima Centauri b.”

Earthy with strange colors

“From the motion of the star we can also deduce that Proxima Centauri B must be slightly larger than Earth.” “It’s about 1.3 times the size,” Lichtenberg continues. But it’s hard to say what that will look like after that. I suspect this exoplanet is completely rocky and somewhat Earth-like, but there’s no evidence for that.

The researcher says: What we know is that everything will have a somewhat strange color. “This has something to do with the star system.” This is a red dwarf star. The light coming from here has a different wavelength than the wavelength of our Sun. You’ll mainly see this on liquid surfaces. For example, the water will appear black.

Eternal days on the exoplanet Proxima Centauri B

Because Proxima Centauri b is so close to its star, the calendar looks very different. The year lasts a little more than eleven days. On the other hand, a day will likely last forever, or a night, depending on which side you’re visiting.

Lichteberg explains that this is due to a phenomenon called synchronous rotation. “Just as we on Earth always look at the same side of the Moon, Proxima Centauri B will likely always face the same side of its star.” This is because the exoplanet revolves around its star at the same speed as it rotates around its axis.

Always the sun

So one side of the exoplanet will be permanently under starlight, and the other will be forever in darkness. This would have serious consequences for the weather on the exoplanet. It gets warmer on the bright side. “This would create a massive flow of wind from the warm side to the cold side.”

This also happens on Earth: warm air moves from an area of ​​high pressure to an area of ​​cooler low pressure. This is how wind is created. But on Earth, warm and cold regions move. The researcher says this is not the case in Proxima Centauri b, because the dark side is always cooler. “As a result, a giant storm is constantly raging from the sunny half of the exoplanet to the dark half.”

Proxima Centauri B is on the horizon

It must be said that many of our ideas about Proxima Centauri b are still very theoretical. After all, we don’t have a picture of the exoplanet yet. Lichtenberg says this may change in the not-too-distant future. “A new super telescope is currently being built in Chile that may be able to see the exoplanet. It should be completed around 2029.”

For those who have more patience, it is also being worked on at the moment A somewhat paranoid plan to travel to a planetary system on a drone ship. With the help of A Light sail This probe will take about twenty to thirty years to complete the journey. It will then take about four years before the images taken by the probe reach Earth. The launch is scheduled for 2036, so it will require a lot of dedication for a planet we’ve never seen before.

Exoplanets come in all shapes and sizes. For example, Proxima Centauri b is a super-Earth. What other types of planets are there?