ESA / Hubble & amp; NASA
• The star closest to the terms of the solar system – Proxima Centauri – a planet with a mass of Earth
• thereon may be liquid water
• discovered by a team of scientists, among which is one Pole
The discovery was officially announced by the European Southern Observatory (ESO) and several other scientific institutions.
– In my opinion the discovery can be considered as the end of a certain stage in the search for extrasolar planets. You do not discover the solar system planets closer to the basic parameters similar to Earth – commented dr. Marcin Kiraga of Warsaw University Astronomical Observatory, which is co-author of the publication in the “Nature”.
Proxima Centauri, the star closest to the terms of the solar system, is a cool star, the so-called. red dwarf. Its diameter and weight are a little more than 10 percent the size and mass of the sun. You can not see it with your naked eye. It is associated with a binary star system Alpha Centauri A and Alpha Centauri B (which in turn is easy to see in the sky in the southern hemisphere).
The newly discovered planet, which was called Proxima b, is very close to Proxima Centauri – only 7 million kilometers from it, which is 5 percent. Earth-Sun distance. Because the star is much weaker than the sun, the planet’s orbit takes place in the so-called. area of life, known also as Ekosfera, ekostrefa or zone habitable. This is the area around a star, with a temperature of enabling the occurrence on the surface of water in the liquid state.
– If we measured the energy flux incoming radiation from the star to the planet, it puts it between Earth and Mars. Roughly 65 per cent. what comes to the Earth and about five times more than Mars. So przysłonecznym point on the planet could hypothetically be water in a liquid state, but it is quite far-fetched assumption, because you have to realize that the planet could be water in liquid form, a planet must have an atmosphere – said Dr. Kiraga.
Despite similar weight and presence in the area of life, the newly discovered planet may prevail conditions significantly different than on Earth. The impact on them can have bursts of ultraviolet and X-rays, which are much more intense than those experienced Earth from the sun. In addition, the effects of gravity may cause the planet faces the star constantly one side, or on one hemisphere, there is a constant day and on the second continuous night.
“pale red dot”
The discovery of the planet is made during the campaign observation Pale Red Dot, whose name can be translated as “pale red dot”. The name refers to the determination of the earth as a “blue dot” (ang. Pale blue dot), which he used once known American astronomer Carl Sagan. The campaign lasted from January to April 2016. Accompanied by observations of a special website with reports of the campaign and popularnonaukowymi articles, and information on a regular basis in social media.
The basis of the campaign were observational studies using the HARPS spectrograph on the 3.6-m ESO telescope at the La Silla Observatory in Chile. This belonging to the European Southern Observatory (ESO) instrument is one of the most precise spectrographs in the world, known for many discoveries of extrasolar planets. The data analysis was also used observations made at other observatories as well as archival data from many years back, up to 2000.
The existence of planets around Proxima Centauri was concluded on the basis of radial velocity measurements – small movements of the star caused by the gravitational influence of a planet.
– The existence of planets around Proxima Centauri seems very likely, it is the best hypothesis explaining the results. These observations have not identified any other reasons, because of which changes might occur radial velocities. These other causes could be changes photometric (brightness of the star) with a period of 11 days, or changes in the shapes of spectral lines associated with the processes taking place on the same star, but no such thing exists – explained Dr Kiraga.
The scientist added that unmistakable confirmation of the existence of the planet would observe the transit, or pass in front of the star. But because of the sizes and orbits a star, it seems unlikely that we can observe from Earth such transit. – For sure, however, they will be carried out further attempts to observe such a phenomenon – he assured.
“The experience of a lifetime”
Polish astronomer pointed out that in comparison with previous reports on the planets around the star Alpha Centauri B (the existence of the planet began to call into question some time after the announcement of the discovery), in the case of Proxima Centauri premises are much stronger.
Currently, the question remains unanswered whether the system there may be more than one planet. Exclusion or the discovery of another planet requires further observation.
– found already many exoplanets and many more will be discovered yet, but the search for the most similar to Earth, and the next, the whole experience of life for us all. Many human history and efforts led to this discovery. The result is also a tribute to them. The search for life on the planet Proxima b will be next – summed up the results of the research leading the team of scientists Guillem Anglada-Escude from Queen Mary University of London.
(zel)
so 41 91.11%
not 4 8.89%
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