This week, an exceptional event happened in Astronomy and I am creating a new category of articles for the occasion. If you had a look at my resume, you know that I am quite interested by this noble science, and indeed today’s article is related to that.
So, this week the scientists of the European Southern Observatory discovered an exoplanet (or extrasolar planet) located roughly 20.5 light-years from Earth near the star named Gliese 581. This is the only one with the presence of water among the 200+ exoplanets found so far by Mankind. This makes that it is quite similar to our good old Earth.
Furthermore, the average temperature is according to the discoverers between -3 °C and 40 °C, the average temperature for Earth being roughly 16 °C. So normally, this particular planet should have some liquid water.
20.5 light-years make around 185,000,000,000,000 kilometres, which is very difficult to just imagine. But compared to the other enormous distances in the galaxy or in the Universe, it is almost next door. As an example, the nearest star to our sun, Proxima Centauri is four light-year away.
For my readers who don’t know what a light-year is, I will explain briefly. This is the distance travelled by light in a year. So if we were going at the speed of light ( 1,079,252,848.8 km/h ) it would take us 20 years and six months to go to Gliese 581 c, the name of the newly discovered planet.
To date, the fastest Human space ship travelled at the approximate speed of 40 thousand kilometres per hour. (source). So taking your vacation to this particular place that is Gliese 581 c is not really for tomorrow, and not even the day after.
Still according to the various sources, this planet is located in the habitable zone, the space where the sun is at a correct distance from the planet to enable life to appear. This indeed makes the discovery even more interesting.
The name of the star Gliese, is the name of the German discoverer. The star was discovered in 1969 and three planets have discovered orbiting around it, including the latest, Gliese 581 c.
According to the International Herald Tribune’s article :
“On the treasure map of the universe, one would be tempted to mark this planet with an X,” said Xavier Delfosse, a member of the team from Grenoble University in France, according to a news release from the European Southern Observatory, a multinational collaboration based in Garching, Germany.”
Still according to the IHT, this planet was discovered in the following way :
“The new planet was discovered by the wobble it causes in its home star’s motion as it orbits, using the method by which most of the known exo-planets have been discovered. Udry’s team used an advanced spectrograph on a 141-inch-diameter telescope at the European observatory in La Silla, Chile.”
To conclude, I would like to state that according to le Figaro, this important discovery will lead to an increased interest in exoplanets and perhaps to missions dedicated to the search of extraterrestrial life. But this won’t be done before 2025.
Further reading and sources :