Earth ceases to be unique
” It’s great news. A breakthrough that opens up new perspectives for astrophysicists. These are two NASA teams who managed to see the light emitted by two exoplanets, that is to say planets located outside our solar system. “
The host of the News March 23, 2005 presents one of the most important detections carried out in astrophysics.
Journalist Catherine François presents a report that explains the discovery. We observed, thanks to the Spitzer infrared telescope, the existence of two gaseous planets which revolve around a sun.
This feat confirms what we already knew since 1995. The Earth is not alone in the Universe.
As early as the 16th century, several astronomers, Giordano Bruno, Nicolas Copernicus and Isaac Newton in particular, postulate that other planets orbit the stars. However, it will take centuries for this hypothesis to be confirmed.
On October 6, 1995, astrophysicists Michel Mayor and Didier Queloz from the Geneva Observatory announced that, by mathematical deduction, they had discovered an exoplanet. Named after 51 Pegasi b, it is located 40 light years from Earth.
Exoplanets that we observe
” And all of a sudden HR8799 showed up. “
In 2008, a team of astrophysicists, led by Professor René Doyon of the University of Montreal, perfected the tracking of exoplanets. Journalist Benoît Giasson tells us the story of their discovery in a report presented at News of November 13, 2008 and hosted by Bernard Derome.
For four years now, René Doyon’s team has been unsuccessfully scanning the sky from the Hawaiian observatory.
One day she points the telescope at the constellation Pegasus using a revolutionary imaging technique designed by one of its members, Christian Marois.
The technique decreases the intensity of the light emitted by the stars.
A miracle then occurs. Three planets appear orbiting around a star.
A second Earth that shelters life?
” It is not a question of if, but of when, we will find a second Earth. “
All of these findings make the question of whether Earth is the only celestial body to harbor life even more relevant.
On February 22, 2017, NASA announced with great fanfare that it had just found seven exoplanets, three of which could resemble Earth.
That evening, the host Céline Galipeau present at the News a report by journalist Frédéric Arnould on the discovery.
The seven planets orbit the star Trappist-1. It is a dwarf star barely larger than Jupiter and cold. Scientists believe that three of these planets could contain liquid water.
If the planet has water, there is a good chance that life could have developed there.
Astrophysicists may have more comprehensive answers in the coming months.
In April 2018, the Transiting Exoplanet Survey Satellite (TESS) was launched from Cape Canaveral, Florida. Its mission is to map almost the entire sky and identify new worlds.
TESS is not, however, designed to detect signs of life.
Soon the James Webb Space Telescope will become operational. He will be able to study the atmosphere of exoplanets and characterize the chemical elements found there.
According to the most recent count, the planets with the potential to harbor life could be numerous.
In August 2018, astrobiologists at the British University of Cambridge identified a group of planets outside our Solar System.
There would exist on these planets chemical compositions similar to those which allowed the appearance of life on Earth.
Among the candidates likely to shelter life, there is the star Proxima Centauri b.
According to an analysis carried out by the Goddard Institute for Space Studies at Columbia University in New York, this exoplanet is rocky. It would also shelter a large surface of liquid water.
Proxima Centauri b is located 40,000 billion kilometers from Earth. It is a neighbor of the Earth on a celestial scale.
If Proxima Centauri b turns out to be uninhabited, let’s not be discouraged.
As of the end of August 2021, no less than 4,512 exoplanets have been officially detected in more than 3,344 planetary systems.
According to the most recent estimates, there are as many as 700 million billion rocky planets in the observable Universe alone.