How can aliens exist

Area 51 - where do the aliens really live?

For some it's a joke, others mean it: 1.9 million people on Facebook agreed to storm the US military area Area 51 in Nevada on September 20. The hard core of the group firmly believes that the US government is hiding UFOs or aliens there.

It was only in 2013 that the American secret service officially confirmed the existence of the Area 51 restricted military area. Residents and visitors had repeatedly seen mysterious objects in flight over the site and speculated that they were UFOs. The US military has been researching new spy aircraft on the site for decades, which could have been the reason for the mysterious flight sightings.

The area in the remote, dry Amargosa Valley became a cult object, which is also repeatedly associated with aliens in numerous films and series. Nearby hotels and restaurants have everything decorated in an alien style.

Researchers are looking for aliens

While conspiracy fans equip themselves for the trip to Nevada and scour the Internet for traces of aliens, scientists worry about extraterrestrial life. Very few people question that this exists: "I would find it very astonishing if extraterrestrial life did not exist," says astrobiologist Dirk Schulze-Makuch from the Technical University of Berlin: "It would be strange with the trillion or more planets and moons, if we were the only place where there is life. "

More on this: Life in space: new search, new happiness

The origin of life - a mystery

Schulze-Makuch is looking for life in its simplest form, i.e. microbes. In doing so, he tries to find the exact conditions under which life can exist. There has to be an atmosphere, he says, or an ice sheet that shields life on the planet.

In addition, it needs a relatively stable air pressure, not too much radiation and still reasonably favorable temperatures. Although microbes can survive even under the most adverse conditions - for example in the Atacama Desert in Chile or at over a hundred degrees in hot springs.

Ultimately, life doesn't work without some kind of fluid. It doesn't necessarily have to be water like it is on earth. It could also be ammonia or methanol. It is often a mistake that we start too much from the conditions that make life on earth possible, explains Schulze-Makuch. Ammonia and methanol are poisonous to us. For living beings on other planets, these substances may even be vital.

More: Astrobiology - Was There Life on Mars?

The search for the second earth

Schulze-Makuch studies the conditions for life in our solar system. Other researchers are looking for planets similar to Earth, deeper in our galaxy, the Milky Way. A little more than 4000 planets have already been discovered outside of our solar system. Around 50 of them should have a suitable mass and a convenient distance to the sun that they are orbiting. A certain distance makes suitable temperatures for living beings possible.

One candidate that is getting a lot of attention right now is the exoplanet Proxima Centauri b. But he only gets it because he is so 'close' to earth, says Schulze-Makuch. Nah, that means 4.3 light years in this case. If at some point it were possible to fly at ten percent the speed of light, it would still take 43 years to get there.

More: Kepler telescope finds ten new Earth-like planets

  • New Rover Generation: This is the NASA Rover Perseverance

    Successful landing

    NASA's Perseverance Rover with the Mars helicopter Ingenuity landed safely on Mars. After two hours of intense tension, cheers broke out at the Jet Propulsion Laboratory in Pasadena, California. At 20:57 UTC on February 18, 2021, the message came that the rover was safely on the surface of Mars.

  • New Rover Generation: This is the NASA Rover Perseverance

    Farewell to the earth

    In early July 2020, NASA engineers loaded the Perseverence (Persistence) Mars Rover into this Atlas V rocket. On Thursday, July 30th, 2020, the trip started from Cape Canaveral.

  • New Rover Generation: This is the NASA Rover Perseverance

    Presentation in the clean room

    This is how it looked when Perseverance was presented to the public in 2019. He will support the most modern rover Curiosity in its work. At just over a ton, the new Rover is 100 kg heavier than its predecessor. And ten centimeters longer at three meters.

  • New Rover Generation: This is the NASA Rover Perseverance

    More powerful than all predecessors

    Perseverance can charge more research equipment and sensors than Curiosity, and its gripper arm with cameras and tools is also more powerful. The new rover can collect samples. It is equipped with 23 cameras and many other instruments. Among other things, he should find out whether oxygen can be extracted from the Martian rocks. But what is there in front of the rover on the Martian floor?

  • New Rover Generation: This is the NASA Rover Perseverance

    A small flying drone

    Correct! A small helicopter is on board. There has never been anything like it on a planetary mission. The use of an aerial drone is new territory for the developers. There is hardly any experience with flight behavior under other atmospheric conditions and gravity that is around a third less than on earth.

  • New Rover Generation: This is the NASA Rover Perseverance

    Curiosity: Working for science since 2012

    Curiosity is the predecessor of Perseverance and the largest Mars rover to date. He landed on the Red Planet on August 6, 2012, has covered more than 14 miles since then and is still extremely fit. It gets its energy from a radioactive isotope battery. So he practically never runs out of power. Curiosity is a complete science laboratory on wheels.

  • New Rover Generation: This is the NASA Rover Perseverance

    Impressive interior

    Curiosity has special spectrometers that can analyze samples remotely with the help of lasers. In addition to temperature, an integrated meteorological station also measures atmospheric pressure, humidity, radiation and wind speed. In addition, the robot has an analysis unit to determine organic compounds - always on the lookout for extraterrestrial life.

  • New Rover Generation: This is the NASA Rover Perseverance

    Don't just scratch the surface

    The rover has already proven that life on Mars is theoretically possible. But he hasn't found life yet. The Curiosity gripper arm has a proper drill. Here he took a sample in 2013 in the yellow knife bay of the Gale crater.

  • New Rover Generation: This is the NASA Rover Perseverance

    Off to the laboratory!

    The sophisticated technology of Curiosity makes it possible for the first time to fill the samples obtained into a wide variety of analysis devices. First, the soil sample passes through a filter system. Then the particles are sorted into different grain sizes by vibration and distributed to numerous analysis devices.

  • New Rover Generation: This is the NASA Rover Perseverance

    Tiny predecessor

    The predecessors were significantly smaller: On July 4, 1997, the NASA Mars rover Sojourner covered its first centimeters on the red planet. It was the first time that a mobile robot set out on its own. It was equipped with an X-ray spectrometer for chemical analysis of the soil and with optical cameras.

  • New Rover Generation: This is the NASA Rover Perseverance

    Size comparison of the Rover generations

    In this photo, NASA employees are standing next to models of three generations of Mars rovers. The little one at the very front is Sojourner - at 10.6 kg not much bigger than a toy car and a maximum speed of one cm / s. At 185 kg, Opportunity weighs more than an electric wheelchair. At 900 kg, Curiosity weighs as much as a small car. The two large ones reach about four to five cm / s.

  • New Rover Generation: This is the NASA Rover Perseverance

    Almost four months in use

    Sojourner was active until September 27, 1997. He has covered a good 100 meters in his life. Here is one of the last photos the Pathfinder lander took of its companion - nine days before reception broke off. The battery must have been unable to cope with the low night temperatures.

  • New Rover Generation: This is the NASA Rover Perseverance

    Paving the way for tomorrow's technology

    Without the experience with Sojourner, the following three Mars rover missions would have been unthinkable. In 2004 NASA landed two identical robots: Spirit and Opportunity. Spirit held out for six years and covered 7.7 kilometers. The robot conquered mountains, took soil samples, and survived winter and sandstorms. On February 13, 2019, I also lost contact with Opportunity.

  • New Rover Generation: This is the NASA Rover Perseverance

    Many technical refinements

    Opportunity had already managed the marathon distance of 42 kilometers in 2015 and thus still had a clear lead over Curiosity. The robot has three different spectrometers and 3D cameras. Most recently he was in the Perseverance Valley - the "Valley of Perseverance". A sandstorm sealed the end of the mission.

  • New Rover Generation: This is the NASA Rover Perseverance

    Landscapes as inspiration

    This image was captured by Curiosity's mast camera. The rover should remain in use as long as possible - another five years and significantly longer. Somehow the surface of Mars doesn't look that unusual - it reminds us of deserts on our planet. Is that supposed to be a reason for wanderlust - or should we leave Mars to the robots?

    Author: Fabian Schmidt


In search of signals from the aliens

If you can't go there and look, you have to look for aliens differently. But if there are other developed civilizations, they should also be able to emit radio waves, thought the researchers at the SETI Institute in California. With huge telescopes they try to register possible radio waves from space. "The most complex part of this is", says project manager Andrew Siemion, "filtering out all the interfering radio waves on earth".

Scientifically, extraterrestrial life has not yet been proven. From a statistical point of view, however, it is likely that if life could arise here on earth, why not elsewhere?

"We thought the earth was the center of the solar system, we thought our solar system was the center of our galaxy, we thought our galaxy was the center of the universe - all of this turned out to be wrong," says Siemion. "We are not as unique as we think."

What if we find them - or they find us

Sociologist Andreas Anton from the Freiburg Institute for Frontier Areas of Psychology and Mental Hygiene is working on what would happen if we actually had contact with extraterrestrials.

Anton describes three possible scenarios. In the signal scenario, Andrew Siemion and his colleagues from the SETI Institute would perceive an extraterrestrial signal. If the signal were 'only' up to 30 light-years away, a young researcher could send an answer and get an answer in his lifetime. Assuming he could even decipher the message.

But the question is also whether it would be a message to us at all or whether we would have just picked up something that was not intended for us at all. Would it be dangerous for us to answer? The British astrophysicist Stephen Hawking, who warned against contact with possibly superior civilizations, was of the same opinion.

The second scenario is the artifact scenario. That would mean we would find an object in our solar system that was made by another civilization. Then we should ask ourselves who should examine it, how and where. Should we bring it down to earth, it could be dangerous if, for example, it is a weapon. And who should research it and possibly learn new technologies?

The most extreme scenario is the direct scenario. Spaceships or probes would land with us on earth. Even if they were unmanned, this would create great uncertainty and perhaps even mass panic and political chaos. It would mean that there is a civilization that is vastly superior to us, says Anton.

"That is why we would do well to think systematically about how we should behave in the worst-case scenario," demands sociologist Anton. For example, how we use rules to prevent mass panic and political chaos and who, as a representative of humanity, makes contact with aliens.

This event is extremely unlikely. But if it did, it would have far-reaching consequences. That is why Anton would like a global committee of experts to draw up an emergency plan for such an extreme case.

One of the oldest riddles of mankind

For Siemion and Schulze-Matuch, the question of extraterrestrial life is one of the greatest questions facing humanity. Anton confirms that the ancient Greeks were already wondering whether we were alone in the universe.

In the Renaissance the question came up again and shortly afterwards the first forerunners of science fiction novels appeared. Even Johannes Kepler wrote a story about possible inhabitants of the moon. Later science fiction novels and films even inspired science, says Anton.

Anton, Siemion and Schulze-Matuch agree on one point. The human fascination with aliens, which is also expressed in the hype surrounding Area 51, is based on the existential question: Are we alone in the universe and if not, is there someone or something out there that is our equal?

  • About UFOs that aren't

    Are humans threatened by alien invasion?

    People keep claiming that they discovered a UFO in the sky. Even if no alien has yet set foot on earth, one reads and hears again and again about strange flying objects in the sky. A lot is hidden behind the supposed spaceships: rockets, drones or helium balloons, for example.

  • About UFOs that aren't

    Do aliens like soccer?

    A mysterious flying object caused a sensation during the 2018 World Cup in Russia. Local residents believed they had sighted a UFO in the night sky over the city of Kazan. But are aliens really interested in soccer? No. It was just a Soyuz rocket with a satellite on board.

  • About UFOs that aren't

    Crash landing at 300 kilometers per hour

    A UFO landed in the desert in Utah, according to American media in 2004. But it wasn't a spaceship, it was the remains of the Genesis space capsule. NASA sent this capsule into space to study the sun. A soft landing was actually planned. Instead, Genesis crashed to the ground at 300 kilometers per hour. The parachute hadn't opened.

  • About UFOs that aren't

    Interstellar comet causes turmoil

    In October 2017 a strange object suddenly appeared in the solar system: Oumuamua. The asteroid got this name because it was first discovered in Hawaii. In Hawaiian, this tongue twister means "ambassador". Now, however, experts are of the opinion that this is more likely a comet than an asteroid.

  • About UFOs that aren't

    Mysterious flying object on the radar

    In December 2017, the Pentagon surprised with the news that they had been researching UFOs for years. After this statement, David Fravor, an ex-fighter pilot, dared to tell of his observation. In 2004 he claims to have seen a UFO during an aerial exercise on the California coast. "Something that wasn't of this earth," was how he described what had appeared on his flight radar.

  • About UFOs that aren't

    UFO sighted in Scotland

    A burning object sped across the sky near the Scottish town of Kippen in September 2018. Internet users are divided on what has really burned in the Scottish sky. Some insist that it was a spaceship. Others speak of a parachutist who ignited pyrotechnics or of a drone.

  • About UFOs that aren't

    The star everyone thinks is a UFO

    "Oh, there's a UFO in the sky!" No, this is not a spaceship with aliens, but Capella. This is the name of the sixth brightest star in the sky. No wonder that the main star in the constellation Fuhrmann ensures that people pick up the phone and report a UFO sighting.

  • About UFOs that aren't

    Helium number balloon held for UFO

    In Neuaubing near Munich, too, a resident believed he had seen a UFO: "It's round, resembles a donut and flies against the wind," was his description. In the end, however, it wasn't aliens who wanted to pay the Bavarians a visit. The flying object was a helium-filled balloon shaped like the number zero.

    Author: Ann-Christin Herbe