Stains on Ceres even more puzzling – rmf24.pl

The mysterious, bright spots on the surface of the dwarf planet Ceres became even more puzzling. White formations on the crater floor Occator discovered over a year ago Dawn spacecraft, scientists have so far not able to explain their origin. Just published in the journal “Monthly Notices of the Royal Astronomical Society” observations from Earth show that the brightness of these spots is changing. Perhaps it creates the material evaporates under the influence of the sun.

         

                              Image Ceres and its white spots on the sky background
                                      / ESO / L.Calçada / NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / Steve Albers / N. Risinger (skysurvey.org) / press materials
                                     

     

Ceres Observations were carried out earlier with the help of circulating around her, sent by NASA probe Dawn. Then he joined the not the European Southern Observatory. Research carried out with the help of the HARPS spectrograph installed on the 3.6-meter telescope at La Silla in Chile showed not only the movement of the stains associated with the rotation of Ceres on its axis, but also surprising additional changes in their brightness. Astronomers suspect that the material forming the spots can disappear under the influence of solar radiation.

Once informed of the discovery of mysterious, bright spots on Ceres, we started to consider the possibility of observing them from the Earth – says the first author of the paper, Paolo Molaro from INAF-Trieste Astronomical Observatory. The more that spin dwarf planet should lead to noticeable differences in the spectrum reflected from the spots and reaching the Earth’s radiation – he admits. Ceres rotation period of 9 hours and the linear velocity of the point on the surface of only 20 km / h. Nevertheless, these differences associated with the Doppler effect with the aid of the apparatus type HARPS measurable.

The observations were carried out in two nights, in July and August last year. To the surprise of researchers, their results showed differences go beyond the changes of the spectrum associated with the rotation of Ceres. It was a real surprise for us – says Antonino Lanza from INAF-Catania Astrophysical Observatory. We have identified this radiation, among these nights, noticeable differences different nature – he adds.

In the article published today, astronomers hypothesize that these changes must be the result of the release of these spots volatile materials that make up the clouds over them, changing the way sunlight glare. These clouds then the melt characteristics and walls were covered with radiation is another change. Dawn probe will have the opportunity to observe a few months Ceres from a height of 385 km. After the end of its mission, the observations of the Earth are likely to continue.

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