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New Supernova, photographed by terrestrial and space instruments. Earth and space tools have captured spectacular multiple images of a supernova, four for precision, produced by the gravitational lens effect of a massive galaxy. This is a very rare result that will allow us to define new limits to the characteristics of dark matter and the universe expansion models.Supernova

New Supernova, photographed by terrestrial and space instruments.

Not one, but more images of the same supernova: it has obtained an international group of astronomers led by the University of Stockholm, documenting a strong gravitational lens effect.Gravitational lensing

New Supernova, photographed by terrestrial and space instruments.

According to a Science article, the observed object is a star that came to the end of its life cycle, exploding, giving rise to a supernova called iPTF16geu, classified as a supernova type Ia. To produce more images of the event was one of the most peculiar phenomena of the cosmos provided by Albert Einstein‘s general theory of relativity. In this theory, the masses are able to bend the space-time fabric, thus deflecting the trajectory of the light rays propagating close to them. Under suitable conditions, a large mass can, therefore, act as a lens against the light coming from objects far from the observer: this is the gravitational lens effect, which in addition to magnifying the image of the source can multiply it.16geu

New Supernova, photographed by terrestrial and space instruments.

In this case, the “lens” is a massive galaxy and the observed source is one of the rarest: a type Ia supernova that is generated when a white dwarf explodes, that is, a particular type of star with a medium to small mass , Which ran out of fuel for the nuclear fusion that kept it “on”. This type of supernova is particularly important for cosmic studies, their apparent brightness only depends on their distance to the observer (the Earth in our case), so they are used as “standard candles”, that is, as a reference to measure the Distance of the galaxy in which they are located.C96Iz

New Supernova, photographed by terrestrial and space instruments.

In two months of measurements, the group observed the supernova iPTF16geu with the Hubble Space Telescope and the Keck Observatory instruments, located on the heights of Mauna Kea, in the Hawaii Islands, and finally with the VLT, the European Southern Observatory In Chile, in addition to the multi-image spectacle – four for precision, circling around the slow-moving galaxy – these sophisticated instruments allow astronomers to accurately measure the time taken by the light of each of the different images to reach us. The differences in the observation times of the light signals allow estimating with great precision the Hubble constant, that is, the universe’s expansion rate.Hubble Space Telescope

New Supernova, photographed by terrestrial and space instruments.

This estimate is fundamental in order to be able to calculate new limits to the physical parameters that define dark matter, that is, a matter that makes up almost 28 percent of the universe but which does not interact with electromagnetic radiation and therefore is not detectable with current instruments; Its distribution. Currently, the different methods to measure the Hubble constant produce somewhat discordant results among them, but these small differences are also decisive in understanding the most plausible scenario for the universe’s expansion process.Astronomers

When viewed for the first time multiple images of a standard candle is a huge advance. We can measure the gravity power of gravity accurately as never before, and so we are able to study physical scales that so far seemed out of reach.

New Supernova, photographed by terrestrial and space instruments.

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To open the video click on the image, good view from your Alessandro Brizzi.



New Supernova, photographed by terrestrial and space instruments.