To figure out if there is life in other parts of the universe, we start with Earth, where there is life now. Finding another Earth is a good way to find aliens. We have found more than 5,000 exoplanets, but we haven’t found Earth’s twin yet. This could change soon, though. Here comes the PLATO mission from the European Space Agency (ESA).

What does PLATO stand for? It stands for PLAnetary Transits and Oscillations of stars. Its goal is very clear. It will look for nearby stars like the Sun that might have habitable worlds like Earth.

“One of the main goals is to find a way to compare Earth and the Sun.” The size of Earth is in the habitable zone of a star like the Sun. “We want to find it around a star that’s bright enough that we can really figure out how heavy it is and how big it is,” Dr. David Brown from the University of Warwick told IFLScience. “If you like, that’s our main goal.”

The telescope is not only an observatory for looking for planets, but it is also an observatory for collecting data on a huge number of stars. The mission team thinks that the fact that it can do both is a key part of why this telescope will be so important.

“You have two parts of the mission.” One is exoplanets, and the other is the stars. “From a scientific point of view, I think it’s pretty cool that these two parts are working together to make the best science we can,” Dr. Brown said.

One of the secondary goals is to make a list of all the planets that are Earth-like and all the star systems that are out there. One more goal is to find other solar systems that are like ours. Even though we don’t know for sure if our little part of the universe is truly unique, it does seem to be different from everything else.

Dr. Brown told IFLScience, “We have a bunch of other scientific goals.” “Really, how well do we know how planetary systems change and grow over time?” Planetary systems are something we’re trying to understand as a whole, not just one planet at a time.

PLATO is different in more ways than just the goals. It is not just one telescope. In fact, it’s made up of 26 different ones. Two of the cameras are fast, and the other 24 are normal cameras set up in groups of six with a small gap between them. This makes the telescope work better, has a wider field of view, and lets you quickly rule out false positives.

It can be hard to tell which of the things you find when you transit exoplanets are real and which ones are not. With the help of several telescopes, we were able to block out some of the mimics that we would have seen otherwise. “Plus, it looks pretty cool,” Dr. Brown said with excitement. “This big square with all of these telescopes pointing at you looks really cool!”

This week, Dr. Brown gave an update on PLATO at the National Astronomy Meeting at the University of Hull. The telescope is being put together and has recently passed important tests. There are no changes to the planned launch date for December 2026. An Ariane 6 rocket, the same kind that made its first launch last week, will take off from French Guiana.

Gravitational waves can be turned into sound very easily. The little chirp changes into little sounds as soon as the blocks hit each other. One of those chirps is my ringtone when my phone has sound, which doesn’t happen very often. The people at Audio Universe have now made the gravitational wave data even better.

In a 3D video, the sounds of gravitational waves hit you from the direction in the sky where it is thought they came from. The sound effects and visualization are both great. There are tiny vibrations in space-time that can hit you as you move your mouse, phone, or VR headset.

Like other sonification projects, it gives blind and visually impaired people a way to get involved in astronomy. It works well with other methods like the Tactile Universe. But that’s not the only reason why they do it.

“We want to do this for three reasons.” It helps researchers look into big, complicated datasets with lots of dimensions. It could be used to make educational materials that are immersive and interesting. Rose Shepherd from Newcastle University says, “It can also make astronomy easier for more people to understand, which is an important thing.” “Making things easier to get makes them better for everyone.”

Being able to listen to the emission lines of celestial objects is one of the most interesting things about sonification for research. As an object moves, its light spectrum peaks spread out, and sonification can make something that is barely noticeable to the eye seem very clear to the ear.

This is helpful in more than one field, though. The group has thought about how adding sound to different datasets could make them better. Warming Stripes is a cool example of this. This is a simple image that shows changes in temperature over time by using a series of stripes, from blue to red. The stripes on the right side get redder as we move from the left to the right. The left side shows decades ago. It is great to see how the climate crisis is getting worse, and now sound adds a little more to it.

“By adding sounds, it can give your data an emotional meaning.” Shepherd explained, “You can use that to show the data how you feel.” “We didn’t mean for the Warming Stripes sonification to make people feel stressed, but it was interesting to see how they reacted instead of just watching the video.”

Audio Universe is making a sonic toolkit that many people can use to make their own resources.

She gave a talk about the audio universe at the National Astronomy Meeting at the University of Hull this week.

Humanity has been trying to find signals from extraterrestrial civilizations for more than a century. Prior to focusing our eyes and ears on the galaxy and universe beyond, early efforts in the Search for Extraterrestrial Intelligence (SETI) concentrated on listening for messages from within the Solar System.

There have been no alien signals found thus far in these searches. While one signal remains enigmatic, it most likely stems from a human or natural source. But given that we (aside from our stray signals) don’t broadcast ourselves on a regular basis, is it unreasonable to assume that alien civilizations would do the same?

Messaging for Extraterrestrial Intelligence, or METI, is introduced. While it wouldn’t be accurate to state that humanity hasn’t communicated with the cosmos, there have undoubtedly been a few. The Golden Records are audio and visual files that NASA’s Voyager I and Voyager II spacecraft “selected to portray the diversity of life and culture on Earth.” Aliens will probably never find these. However, we have also sent other signals, like the Arecibo Message, which was directed about 21,000 light-years from Earth toward the globular star cluster M13. With only 210 bytes of data, the message was small but contained information about the 4 billion people that lived on Earth at the time, a stick figure of a person, a double helix, and a drawing of the Arecibo radio telescope that sent the message.

The organization METI International was founded in 2015 with the intention of communicating with extraterrestrial civilizations. They delivered a similar message to the super-Earth exoplanet GJ273b in October 2017, which is only 19 light-years away from Earth and may be habitable.

This is where METI becomes a little contentious. A map of the solar system was also included in the Arecibo message, and there are (very speculative) reasons why we might not want to communicate with aliens in our cosmic backyard or even send a return address.

The explanation of the Fermi paradox offered by what is now widely referred to as the “Dark Forest Hypothesis” is one of the reasons METI is controversial.

In short, it looks like the universe is full of planets that might be habitable, but we have never picked up a signal from an alien civilization.

The very dark Dark Forest Hypothesis, which is explained in Liu Cixin’s Remembrance of Earth’s Past trilogy, says that alien civilizations hide their existence because you can’t be sure what other civilizations want. There’s no way for you to know if they are hostile or friendly, or what their intentions are.

It’s possible that you, as a friendly civilization, find an alien civilization that is also friendly and about the same level of development as yours. You know you’re nice, but you don’t know if they’re also calm. Even worse, because of how far away these civilizations are and how long it takes to receive light and signals from them, you have no idea how their society has changed since the signal from them reached yours. In the meantime, they may have made huge technological leaps. This means that even if the planet you are looking at seems peaceful and not too far ahead of yours, everything could have changed by the time the light gets to you.

On top of that, there is the pressure of resources. According to the books, you also know from your own planet that life uses and spreads all the resources it can find. But there are only so many resources in the universe.

You still have to deal with the fact that you don’t know if they know that you are peaceful if you decide that they are peaceful. Since they think or even just suspect that you are bad, it makes sense that they would try to kill you before you could kill them. You could talk to them, just like you can here on Earth, to reassure them even more of your plans. In space, though, it could take hundreds or even thousands of years for your new message to get there. During that time, they could have began an attack to destroy you. With this many red flags, Liu comes to the conclusion that the only smart thing for a civilization that wants to stay alive is to hide in the forest and kill any civilizations that make noise, before they kill you.

Scientists are serious about the idea of hostile aliens, even though the idea became popular in fiction. In 2015, Stephen Hawking started a project to look for alien civilizations. He talked about why it might not be a good idea to say hello back.

According to Space.com, Hawking told the crowd, “We don’t know much about aliens, but we know a lot about humans.” “If you look at history, interactions between humans and less intelligent creatures have often been terrible for them, and interactions between civilizations with advanced and primitive technologies have also been bad for the less advanced.” If someone reads one of our messages, they might be billions of years ahead of us. They will be much stronger if that’s the case, and they might not value us more than we value bacteria.

However, the Dark Forest theory is still a long way from being proven. It is important to think about hostile aliens when deciding whether to contact other species and who should make that decision. David Brin, an American author and scientist, asked “whether small groups of zealots should bypass all institutions, peer critique, risk appraisal, or public opinion, to shout ‘yoohoo’ into a potentially dangerous cosmos.”

In a way, the fact that METI exists could be used to show that the Dark Forest Hypothesis is wrong. Let’s say there are very advanced societies out there. Assuming that some people in these advanced civilizations have access to advanced broadcast technology is a reasonable thing to do. Another reasonable guess is that if they were that advanced, they would have built this civilization with science instead of magic.

The civilizations would probably gather information about other star systems in the same way that we do, unless they have a good reason for not wanting to know about life beyond their own planet. Assuming that this information and broadcast technology aren’t somehow limited across all civilizations, there must be some people who would be crazy enough to try to get in touch with other civilizations. While obviously speculating wildly, it’s possible that an alien METI species that likes to take risks might try to warn other, younger civilizations about how the universe is like a dark forest. Also, we haven’t heard from these actors, which could mean that the long silence has a different cause than the Dark Forest Hypothesis.

That, or the METI problem, might only happen in new civilizations that send out messages every so often before we learn about the universe’s dark side and do everything we can to stay quiet.