Image copyright J Skowron / Warsaw University Observatory
They looked dark and found a high gloss.
Astronomers captured with the help of Las Campanas Observatory in Chile – a rare images of a small star before and after it exploded in a classical nova
The observations, made by Polish scientists and published in the journal Nature , were part of a multiyear study of the sky whose original purpose was to detect dark matter.
It was this constant flow of images that feeds this project on dark matter which allowed experts to review the data of years ago and realize how the star system was seen in May 2009.
Even though the event occurred at 20,000 light years -generando a very, very faint point of light, barely visible among the twinkling star is an excellent opportunity to study the process in which it occurs a classical nova .
“Thanks to our long-term observations is that we could detect this nova few years before and a few years after the explosion,” he told the BBC Przemek Mróz, first author and doctoral student at the Astronomical Observatory of the University of Warsaw.
“This is very unusual because usually the nova only attract attention when they are very bright, when are erupting. “
hypothetical Hibernation
These violent events, but little understood usually start with a white dwarf (the dead remnant of an average star as our Sun) that is trapped in a very small orbit of an active star .
“The distance between these two stars is very small, in fact a solar radius” Mróz he said.
“Imagine that inside the Sun have two stars orbiting each other,” he said.
that orbit is so tight that in this case only takes five hours cross it, allowing the dwarf constantly steal gas most passenger.
This extra matter accumulates on the surface of dwarf until an explosive thermonuclear reaction only shatters the foreign matter occurs, leaving behind the white dwarf.
“the whole system survives blast nova, which makes the process start again, “said the expert.
” in a few thousand years our nova reawaken and exploded, but we will not be here to see it. “
This does not happen with type Ia supernova , which begin in the same way but have a much stronger explosion destroys the white dwarf.
Mróz and colleagues believe that your research results support the model of “hibernation” of a classical nova .
This means that during the long wait between explosions the system the white dwarf dela taking gas from its neighbor shuts down almost completely.
This model predicts a slow mass transfer among the stars before the explosion, and a relatively quick and bright after transfer; which is precisely what experts believe they have captured Poles.
may not
Other astronomers were less convinced.
“The question is still being cooled, is not yet stable, so We do not know how it will be its luster long term after the eruption ” said Christian Knigge from Southampton university in the UK.
“This is because we are still seeing the end of pop”.
As any scientist who is respected, want to see more data.
“This is very circumstantial,” he told BBC professor Knigge. “But as observations as evidence for our theories of how the explosions work, is really fantastic “.
“(This) allows us to measure how was the brightness and conditions prior the eruption, we can use it to our model of eruption, we have a good measure of how long it takes to decline, and we will be following “
the British expert does not believe the data from this study go. to clarify the theory of classical nova, “but from my point of view, is too early to say that this is a case of hibernation system now erupted”.
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