Alien life will be found very soon, British astronomy professor says
Humanity will discover extraterrestrial life on distant worlds in the coming years, a top British astronomer predicted.
Professor Sasha Hinkley, an associate professor of astrophysics at the University of Exeter, said it was ‘increasingly likely’ that the telltale signs of extraterrestrial life would be discovered ‘within its lifetime’.
He said devices such as the powerful $10bn (£7.4bn) James Webb Space Telescope are poised to discover “biosignatures” – atmospheres on exoplanets containing gases emitted by living things, such as oxygen found on could point to life.
Prof Hinkley added that even if ‘biosignatures’ were found, it may not indicate signs of an alien civilization on a distant world.
The scientist’s comments come as a task force of experts from the UK, US and Switzerland insisted extraterrestrial life would be found on thousands of worlds in the next 10 to 20 years, in what would be the greatest discovery in human history.
Prof Hinkley said: ‘The probability that life exists in some form in the universe is quite high. I would even say that it is becoming more and more likely that the discovery of life on an exoplanet will happen in my lifetime.’
But the astrophysicist said that even if telltale signs of life were detected on distant worlds, it doesn’t necessarily mean an alien encounter.
“To be clear, the discovery of life on another planet does not necessarily mean that an alien civilization exists on another planet, nor that we are about to have some form of communication with such life forms,” added he adds in his article The spectator.
Discovery: NASA’s James Webb telescope has already detected carbon dioxide for the first time in the atmosphere of a planet outside our solar system. The technology could be used to detect the telltale signs of life on other planets. This illustration shows what exoplanet WASP-39 b might look like
‘The evidence of the discovery of life will likely be found by observing imbalances in the ratios of chemical species (e.g. ozone and carbon dioxide), which otherwise would not exist naturally without possibly some form of biological activity driving this imbalance .’
One hundred million worlds in our galaxy could host extraterrestrial life, according to a “conservative” prediction from NASA.
And the space agency claims we’ll be able to find that life in 20 years, with a high probability that it will be outside our solar system.
Devices such as the James Webb Space Telescope, launched in 2021, are already observing the cosmos in unprecedented detail.
Its mission is to advance humanity’s understanding of how planets, stars and galaxies form and evolve.
Other high-tech space kits are already in the pipeline, Prof. Hinkley said, and NASA is now tasked with developing a space mission by 2040 to search for biosignatures on exoplanets.
Launched in 2021, the James Webb Space Telescope is humanity’s latest tool to detect extraterrestrial life in the cosmos. The device’s mission is to deepen the understanding of how worlds, stars and galaxies are formed. Pictured is the huge mirror of the telescope being lifted in April 2017 at the Goddard Space Flight Center in Greenbelt, Maryland
Space telescopes can already analyze starlight passing through a planet’s atmosphere to determine its chemical composition.
In August, astronomers announced that carbon dioxide had been detected by the James Webb telescope in the atmosphere of a Saturn-sized planet 700 light-years away.
It was the first time scientists could say with certainty they had detected gas on a planet outside the solar system.
Particular attention is paid to planets, the ‘Goldilocks zones’, where scientists believe life is most likely to evolve and flourish.
Planetary orbits in this zone are neither too close nor too far from a star, creating ideal conditions for the existence of liquid water – believed to be a key ingredient for life to emerge.
It is believed that there could be trillions of habitable planets in the universe and hundreds of millions in our galaxy alone.
Among the discovered exoplanets is Kepler-186f, an artist’s image. It’s the first Earth-sized planet to be found in a star’s habitable zone, and could be a signal that there are Earth 2.0s waiting to be found in Kepler’s data
Prof Hinkley said one of the best potential regions for life in the Milky Way was the planetary system TRAPPIST-1.
Located about 40 light-years away, the system is populated by seven “Earth-sized planets” closely orbiting a “very dim and cool star not much larger than Jupiter,” said Prof. Hinkley.
He added: “Three of the planets orbit TRAPPIST-1 in the habitable zone of their parent star. Attempts are already being made to target these three planets with the James Webb telescope, looking for what scientists call “biosignatures.”
To date, scientists have spotted 5,332 confirmed exoplanets in some 3,931 planetary systems.
But this isn’t even the tip of the iceberg. For comparison: there are about 100 billion stars in our Milky Way.’ Professor Hinkley added.
The discovery is important because it suggests the $10 billion observatory (pictured) may be able to detect and measure the gas in the thinner atmospheres of smaller, rocky planets that could harbor life
Webb’s infrared capabilities allow it to “look back in time” at the Big Bang, which happened 13.8 billion years ago. Light waves move extremely fast, about 186,000 miles (300,000 km) per second, every second. The further away an object is, the further back in time we look. This is due to the time it takes for light to travel from the object to us
“Since we now know from several space missions that most stars host planets, this starts to give you an indication of how many exoplanets might exist in our galaxy.
“And then, beyond our galaxy, there are an estimated 200 billion galaxies in the universe, each potentially containing hundreds of billions of stars with their own exoplanets.”
Last month, Dr Emily Mitchell of the University of Cambridge believed it is ‘highly likely’ that signs of extraterrestrial neighbors will be found, as life is almost certainly ‘quite common’ in the universe.
She said, “We only have one biosignature, here on Earth. But my optimistic colleagues suggest that in 10 or 20 years we will have thousands of biosignatures. We can then calculate how we relate to life on other planets.’
How scientists study the atmospheres of distant worlds in search of extraterrestrial life in the cosmos
Distant stars and their orbiting planets often have conditions unlike anything we see in our atmospheres.
To understand these new worlds and what they consist of, scientists must be able to detect what their atmospheres are made of.
They often do this by using a technique called absorption spectroscopy.
This form of analysis measures the light coming from a planet’s atmosphere.
Each gas absorbs light of a slightly different wavelength and when this happens a black line appears on a full spectrum.
These lines correspond to a very specific molecule, which indicates its presence on the planet.
They are often referred to as Fraunhofer lines, after the German astronomer and physicist who first discovered them in 1814.
By combining all the different wavelengths of light, scientists can determine all the chemicals that make up a planet’s atmosphere.
This analysis must be done by space telescopes like James Webb because otherwise the Earth’s atmosphere would interfere.
Absorption of chemicals in our atmosphere would skew the sample, which is why it’s important to study the light before it has had a chance to reach Earth.