Sky naked NAKED-EYE NOVA IN CENTAURUS

Posted by Elijah on August 26th, 2022

A nova has emerged just west of Alpha and Beta Centauri, though it is hidden from view from the majority of the Northern Hemisphere. On December 2nd, nova hunter John Seach in Australia captured it using a DSLR patrol camera at about magnitude 5.5. Previous images he took on November 26 showed nothing there to be brighter than 11th magnitude. When Steven Graham in New Zealand checked the images from his wide-sky nude, he discovered that the nova was visible between December 1 and December

The up-close photo to the right was captured on the third by Ernesto Guido, Nick Howes, and Martino Nicolini using a remotely controlled 20-inch telescope. By late on the third UT variable-star observers estimated its magnitude to be 4.7 or 4.6, and spectra displayed the prominent hydrogen emission lines of a nova.

Sebastian Otero in Argentina discovered it to be magnitude 4.3 by 6:37 UT on the 4th. That's a tiny bit brighter than the closely watched Nova Delphini 2013 at its brightest in August of last year. Here is the AAVSO light curve for the most recent nova.

Will it get any brighter? Go outside and take a look if you're in the Southern Hemisphere! Before your local sunrise, the nova is in the south-southeast at right ascension 13h 54m 45s and declination —59° 09.1′. It is situated near a star that was once 15th magnitude and may have been the progenitor.

The initial identifier for it was PNV J13544700-5909080. Nova Centauri 2013 is now. Here is a comparison-star chart from the AAVSO that is 10° wide. The bright star is Beta Cen, and the nova is in the middle of the graph.

When a relatively normal star streams hydrogen onto the surface of a companion white dwarf in a tightly orbiting binary star system, a nova can occur. The bottom of the layer explodes in a runaway hydrogen-fusion reaction, creating a hydrogen bomb that takes the form of a thin shell around the star when the layer of fresh hydrogen on the white dwarf's surface becomes sufficiently thick and dense. The process may repeat in a few years to tens of thousands of years depending on how much new hydrogen accumulates and how well the underlying white dwarf is preserved.