Beta Aurigae Eclipsing Binary Star and the Galactic anticentre

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Space between Gemini, Auriga and the Lynx - Canon 600d DSLR with EOS 18-55mm lens at f=15mm on a Star Adventurer equatorial mount. Image by Pip Stakkert. Plate solving by Astrometry net.

" Beta Aurigae is an unusual and interesting binary star system. It has an official arabic name  Menkalinan and can be seen with the naked eye when the constellation Auriga is visible in the night sky. It is the second brightest star in the constellation after Capella and is approximately 81 light years distant from Earth. The binary star system comprises two metallic-lined subgiant stars having A type stellar classification. The two stars are roughly the same diameter and same mass and revolve around a common centre of gravity. Both are hot stars that emit blue-white hued light, because they are so close together they cannot be resolved as two stars by visual or photographic means. Over a period of 3.96 days their combined apparent magnitude varies between +1.89 and +1.94 as every 47 hours and 30 minutes one star partially eclipses the other as viewed from Earth. Metallic-lined stars have unusual spectra exhibiting strong and often variable absorption lines for metals such as zinc, strontium, zirconium and barium and deficiencies in others such as calcium and scandium. These chemical abnormalities are the result of some light absorbent elements being pushed to the surface whilst others sink due to gravity. For this to take place the star must have a low rotational velocity. Normally, stars classified as A have high rotational velocities. In the case of the binary star Beta Aurigae the rotational velocity of each star has been reduced by gravitational tidal affects. Beta Aurigae has a much fainter companion star in attendance which may be gravitationally linked. So Beta Aurigae may indeed be a triple star system.

Our galaxy the Milky Way has a centre as viewed from our planet in the constellation Sagittarius. The 'Galactic anticentre' from our perspective resides in the constellation Auriga close to the star Menkalinan". - Kurt Thrust acting CEO and current Director of the Jodrell Plank Observatory.

" Although the winter Milky Way runs nearby, when we look out in the direction of the constellation Auriga we are looking out along the galactic disc into deep space. There is much less dust here in the outer spiral arms of the Milky Way and this enables us us to see distant open star clusters like Messier 37 and NGC 2281" - Karl Seguine Outreach Coordinator at the Jodrell Plank Observatory.

Credit: Wikipedia

Type 1a Supernova SN 2020ue in Galaxy NGC 4636

"The Type 1a Supernova 2020ue was discovered in the elliptical galaxy NGC 4636 on the 12th January 2020 by Koichi Itagaki. The image taken by the COAST Robotic Telescope on the 31st January was at about peak visual magnitude. 

Type 1a Supernova occur in binary star systems when a carbon-oxygen white dwarf near the Chandrasekhar limit accretes enough material from a companion star to exceed the limit and therefore collapse triggering a thermonuclear detonation . Such events produce extremely luminous supernovae. 

The variation in maximum luminosity of Type 1a Supernovae is quite small and this is thought to relate to the small range of masses for the stellar cores that explode. As a consequence of high and uniform luminosity, Type 1a supernovae are useful as 'standard candles' in the calculation of distances to very distant galaxies". -  Karl Seguine - Community Outreach Officer

"Pip Stakkert managed to request the COAST robotic camera on Mount Teide to capture this image of the supernova just a few days after its discovery and before its luminosity began to fade. 

Supernovae are very luminous indeed but the universe is vast. When you view the little dot of light in this image it is hard to imagine how luminous this supernova is because it is so very very far away. 

NGC 4636 is between 42 and 64 million light years distant in the constellation Virgo. Put another way, it is approximately 310,000,000,000,000,000,000 miles away. The total energy output of this supernova may be 10e+44 joules, or as much as the total output of the sun during its 10 billion year lifetime. In terms of nuclear explosions = 239,005,736,137,667,280,000,000,000,000 megatons of TNT. A big bang indeed Moriarty!

If you wish to find out more about this supernova or supernovae in general follow the links". - Kurt Thrust acting CEO and current Director of the Jodrell Plank Observatory


http://www.rochesterastronomy.org/sn2020/sn2020ue.html

https://britastro.org/node/20392

https://en.wikipedia.org/wiki/Chandrasekhar_limit

https://en.wikipedia.org/wiki/Type_Ia_supernova

https://en.wikipedia.org/wiki/Type_II_supernova

Credit:telescope.org and the Open University

Venus and Mercury in the late Afternoon

Venus top left and Mercury bottom right just after sunset looking west. Canon 600d DSLR and EF 75-300 zoom lens at approx f=200mm. One RAW 1/15sec exp at ISO6400.

" The Jodrell Plank Observatory is located at approximately sea level +10 metres and 2 miles from the UK's most easterly point, so obtaining an image of Mercury low in the west at sunset is quite difficult. Jolene McSquint-Fleming captured this great widefield view of the planets Venus and Mercury whilst undertaking maintenance on the Observatory roof. Gosh! - What that woman doesn't know about astrophotography and using a blowlamp is not worth knowing" - Kurt Thrust acting CEO and current Director of the Jodrell Plank Observatory.