Scientists say aliens may be hiding in ‘terminator zones’ on distant exoplanets
aliens may hide in special “terminator zones” on distant planets, where it is not too hot and not too cold, scientists say.
Many exoplanets are planets beyond our own. solar system – are tide-locked, meaning that one side is always facing the star they orbit, while the other side is in constant darkness.
Astronomers from the University of CaliforniaIrwin discovered that there is a band around these planets that could contain liquid water, a key component of life.
This is called the “terminator zone”, where the terminator is the dividing line between exoplanetday side and night side.
Any water that is reachable will likely freeze on the cold night side, but the bright day side will be so hot that it will evaporate.
Astronomers at the University of California, Irvine have discovered that tide-blocked exoplants have a band around them that could contain liquid water, a key ingredient in life.
Lead author Dr Ana Lobo said: “The day side can be very hot, far beyond habitability, and the night side will be icy and may be covered in ice.”
“There might be big glaciers on the night side.
“You need a planet that is in the sweet spot with the right temperature for liquid water.”
Everything that has mass has gravity, and the more massive it is, the stronger its gravitational pull.
In the case of a planet orbiting a star, the gravitational force of the star pulls the planet towards it, while the planet’s own gravity also pulls it towards the star.
The orbital path of a planet is determined by a combination of these forces, as well as the speed and direction of its movement before it is fixed in orbit.
If the planet orbits very close to the star, the star’s gravity can distort the planet’s shape so that it bulges out on one side.
The gravitational force felt by this bulge is stronger than in other regions of the planet, so it begins to slow the planet’s axial rotation.
Eventually, this slows down to the point where the rotation stops completely and only the bulbous side faces the star, causing it to become tidally blocked.
Tide-blocked exoplanets most likely exist around M-dwarf type stars, a type of red dwarf that is colder and smaller than our Sun.
This is because smaller stars are more likely to trap smaller exoplanets in their orbit, which are more susceptible to tidal forces than larger ones.
Many exoplanets are tidally locked, meaning that one side is always facing the star they orbit, while the other side is in constant darkness. Pictured: surface temperature (°C) of various simulated tide-blocked exoplanets. Black lines represent the terminator
Because M dwarfs make up about 70 percent of the stars seen in the night sky, tide-blocked exoplanets are considered relatively common.
For his research, published in Astrophysical journalThe researchers wanted to find out if these planets have the conditions to support life, such as the ability to hold water in liquid form.
If so, this would greatly increase the number of planets that astronomers could study for extraterrestrial life.
The researchers modeled the climates of several tide-locked exoplanets by looking at their varying temperatures, wind patterns and radiative forcing.
They used software commonly used to model the Earth’s climate, but slowed its rotation on its axis.
This highlighted the “necessary” zone around the terminator of these planets, which could contain liquid water, which ensures the existence of life.
However, this was only the case when the planet had a lot of land, as if it were largely covered by an ocean, the water on the dayside would evaporate and cover the planet in steam.
This will change the temperature of the terminator zone and make it uninhabitable.
“Ana showed that if there is a lot of land on the planet, the scenario we call “terminator habitability” can exist much more easily,” said study co-author Dr. Aomawa Shields.
“These new and exotic habitability states that our team is discovering are no longer the stuff of science fiction – Ana has done the work to show that such states can be climate stable.”
Most studies evaluating the potential for life focus on water-rich planets.
Dr. Lobo said: “We’re trying to draw attention to water-limited planets that, despite not having extensive oceans, may have lakes or other smaller bodies of liquid water, and this climate could actually be very promising.”
The researchers say they believe astronomers have proven for the first time that they have the potential for life in the terminator zone of exoplanets.
Their discovery could mean that scientists looking for signs of life on exoplanets should be aware that they may be hidden in certain areas.
It also increased the number of planets to search for, including those not heavily covered in water.
“By exploring these exotic climate states, we increase our chances of finding and correctly identifying a habitable planet in the near future,” Dr. Lobo said.
KEY DISCOVERIES IN HUMANITY’S SEARCH FOR FOREIGN LIFE
Discovery of pulsars
British astronomer Dame Jocelyn Bell Burnell was the first person to discover a pulsar in 1967 when she spotted a radio pulsar.
Since then, other types of pulsars have been discovered that emit X-rays and gamma rays.
Pulsars are essentially spinning, highly magnetized neutron stars, but when they were first discovered, it was thought they could come from aliens.
‘Wow!’ radio signal
In 1977, an astronomer looking for alien life in the Ohio night sky noticed a radio signal so powerful that he excitedly wrote, “Wow!” next to his date.
In 1977, an astronomer looking for alien life in the Ohio night sky noticed a radio signal so powerful that he excitedly wrote, “Wow!” next to his date
The 72-second explosion, seen by Dr. Jerry Eyman through a radio telescope, was from Sagittarius but did not match any known celestial object.
Conspiracy theorists have since argued that “Wow! The signal, which was 30 times stronger than the background radiation, was a message from intelligent aliens.
Fossilized Martian Microbes
In 1996, NASA and the White House made a big announcement that the rock contained traces of Martian bugs.
The meteorite, cataloged as Allen Hills (ALH) 84001, fell into the frozen wastelands of Antarctica 13,000 years ago and was discovered in 1984.
Photographs were released showing elongated, segmented objects that appeared startlingly lifelike.
Photographs have been released showing elongated, segmented objects that look startlingly lifelike (pictured).
However, the excitement did not last long. Other scientists wondered if the meteorite samples were contaminated.
They also argued that the heat released when the rock was ejected into space could create mineral structures that could be mistaken for microfossils.
Tubby Star behavior in 2005
The star, also known as KIC 8462852, lies 1,400 light-years away and has baffled astronomers since its discovery in 2015.
It is dimming much faster than other stars, which some experts believe is a sign that aliens are harnessing the star’s energy.
The star, also known as KIC 8462852, is located 1,400 light-years away and has been baffling astronomers since its discovery in 2015 (artist’s impression).
Recent research has “eliminated the possibility of an alien megastructure” and instead suggests that the dust ring may have been causing strange signals.
Exoplanets in the Goldilocks zone in 2017
In February 2017, astronomers announced they had discovered a star system with planets that could support life as little as 39 light-years away.
Seven Earth-like planets have been found orbiting the dwarf star Trappist-1, and each of them could have water on the surface, one of the key components of life.
The three planets are in such good conditions that, according to scientists, life could already have developed on them.
The researchers say they’ll know if there’s life on any of the planets within a decade and say, “This is just the beginning.”