NGC 6302 (also Bug Nebula, Butterfly Nebula, ESO 392-PN5, Sharpless 6, RCW 124, Gum 60, Caldwell 69 and GCl 70) is a magnitude +7.1 planetary nebula located 3400 ±500 light-years away in the constellation Scorpius. The spectrum of NGC 6302 shows that its central star is one of the hottest stars in the galaxy, with a surface temperature in excess of 200,000 K, implying that the star from which it formed must have been very large.
The nebula was discovered by Scottish astronomer James Dunlop using a homemade 9-foot 22.86 cm (9 inch) f/12 speculum Newtonian reflector at Paramatta, New South Wales, Australia, on the 5th June 1826.
Right Ascension 17h 13m 44.211s, Declination -37° 06' 15.94"
Astronomers at The University of Manchester's Jodrell Bank Centre for Astrophysics have discovered one of the hottest stars in the Galaxy - with a surface temperature of around 200,000 degrees, it is 35 times hotter than the Sun. Despite numerous attempts by astronomers across the world, the mysterious dying star at the heart of the Bug nebula - one of the brightest and most beautiful of the planetary nebulae - has never been seen before.
Astronomers at The University of Manchester's Jodrell Bank Centre for Astrophysics have discovered one of the hottest stars in the Galaxy with a surface temperature of around 200,000 degrees - 35 times hotter than the Sun. Read more
Astronomers have taken the first pictures of one of the hottest stars in the Galaxy. The temperature on its surface is 200,000C, 35 times hotter than the Sun. The mysterious dying star at the heart of the Bug Nebula - 3,500 light years away in the constellation Scorpius - has never been seen before as it is hidden behind a cloud of dust and ice. A team of astronomers at the University of Manchester's Jodrell Bank Centre of Astrophysics, led by Professor Albert Zijlstra, recorded the images using the recently refurbished Hubble Space Telescope. They will be published in the Astrophysical Journal next week. Source
The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects, and NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the central star of this particular planetary nebula is exceptionally hot though -- shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. Above is a dramatically detailed close-up of the dying star's nebula recorded by the Hubble Space Telescope. Cutting across a bright cavity of ionised gas, the dust torus surrounding the central star is in the upper right corner of this view, nearly edge-on to the line-of-sight. Molecular hydrogen has recently been detected in this hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation Scorpius.
High resolution spectroscopy of the Bug Nebula (NGC 6302) by the Gemini South observatory has revealed hyperfine structure in the 3.66 micron line of ionized aluminium. A joint Chile-United Kingdom team led by Simon Casassus (University of Chile) used the NOAO-built Phoenix near-infrared spectrometer to obtain high-resolution spectra (R~75,000) of the [Al VI] 3.66-micron line region in the planetary nebula. By modelling the multi-component structure of the line, the team has been able to derive values for the electric quadrupole constant in the [Al VI] transition and measure a reliable isotopic ratio for aluminium. The derived isotopic ratio of Al-26/Al-27 is less than 1/33 in NGC 6302. This is the first time such a constant in an atomic transition has been measured in any astrophysical object.
The isotopic ratio of Aluminium (Al-26/Al-27) is of interest because it is a signpost of recent nucleosynthesis. Al-27 is the stable isotope, while Al-26 is radioactive (with a half-life of 720,000 years). Because the ratio is poorly established, the origin of Al-26 is currently thought to be produced by a variety of different processes ranging from nova detonations to cosmic-ray collisions in molecular clouds. This is the most stringent upper limit on the relative Al-26 abundance in any astrophysical object to date. Although the measurement is not constraining enough to quantify the Al-26 production in Asymptotic Giant Branch stars, which are the progenitors of planetary nebulae like NGC 6302, the technique is established.