If you live on in a farsighted but narrow part of the world , you have an chance next calendar month to contribute to a global project exploring one of the most renowned and enigmatic principal . That ’s because on December 12 , on a path run almost half the style around the planet , the asteroid 319 Leona will pass by in front of Betelgeuse , briefly halt its light . That could be a fun thing to see , something that will be possible without a telescope , but the details on how it happens could examine very scientifically revealing .
Betelgeuse is no ordinary genius . As well as being the 10thbrightest in our sky on intermediate , it has the second largest angulate diameter if you do n’t count the Sun . As a very evolved genius , it ’s probably our best fortune to get a front - wrangle tush at a supernova , although debate cover as to whether that’sdecadesor almost100,000 yearsaway .
Uncertainty like that make any entropy we can find out about Betelgeuse unambiguously worthful . Nevertheless , when we ca n’t see it seems like an unmated metre to get the adept info . It ’s not as though anyone seek to take Betelgeuse during the day or on cloudy nights .
The current estimate of the occultation path (subject to slight revisions in red and green, with night areas inside the purple and yellow lines.Image Credit: Occultwatcher.net. Last update SteveP
Nevertheless , many astronomers consider the timing excellent . Known as an eclipse , the musical passage will imply that anobserver in the right placewill see about 94 per centum of Betelgeuse ’s light stymie , briefly reducing it to the status of a very average superstar .
The reason this could be utilitarian is that Betelgeuse is so raggedly undimmed across its surface . This is n’t a consequence of starspots , but itsenormous convection cells , which also contribute to its overallvariable brightness . However , it can be hard to map the dispersion of these electric cell , because glare from the brighter parting interferes .
By compare the way Betelgeuse blind from unlike locations along its way of life we may be able-bodied to map the cells ’ distribution better than we have ever been able to do before . However , most of the way of life from which the occultation will be visible is over the Atlantic Ocean or the Mediterranean , and the betting odds are some of the earth will be cloud over . That makes it crucial that observations are convey from as many billet as possible , and professional astronomer would like amateurs ’ assistance .
Even a simple-minded DSLR television camera with no telescope can allow for utilitarian information if correctly located . However , at the recentEuropean Symposium for Occultation Projects , astrophotographer Bernd Gährkenstressedit is essential that we know the exact timing and positioning of any observation . There are apps forAndroidandiPhoneto help anyone who may be able to enter .
The event is of such significance that scads of astronomers studied an eclipse by 319 Leona on September 13 this year of a nameless genius that ask a small scope to see .
“ In the overpowering majority of the stellar occultations the diameters of the star are midget compared to the angulate size of the solar organisation eubstance that passes in front of them so the eclipse are not gradual , but in this compositor’s case , the immense angulate diameter of Betelgeuse will give ascent to a different phenomenon of ‘ partial occultation ’ and ‘ total eclipse ’ ( provided that Leona ’s angulate diameter is big enough compared with that of Betelgeuse . ) ” The authors designate out .
Observing the September case helped polish Leona ’s orbit and build . improving anticipation of where the December event will be visible .
Prior to the realization of where its path was taken , 319 Leona was not considered a particularly interesting asteroid . It ’s 70 kilometers ( 40 miles ) across - bigger than most we know , but hardly a elephantine - and orbits towards the out part of the main asteroid knock . Leona is dark and ruddy in coloration and is considered a P - type asteroid that rotates slowly , taking around 18 days to turn around .
That mean that in the 17 minutes the eclipse will be seeable somewhere , Leona ’s rotation wo n’t be much of a factor .
Curiously , preparations are hindered by the fact that we live Betelgeuse ’s position in the sky less on the dot than most star . This heel counter - intuitive fact is a result of the Gaia blank telescope being too dazzled by the brightest stars to commit them . Other methods are less precise than Gaia . uranologist are struggling to resolve conflicting estimate of Betelgeuse ’s accurate location prior to the event , as it will move precisely where they need to be to see the occultation happen .
The study of Leona ’s September occultation has been accepted forAstronomy and Astrophysics Letters . A preprint is usable onArXiv.org
