The Vela supernova remnant is a supernova remnant

Supernova remnant

A supernova remnant is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way.There are two...

 in the southern constellation Vela

Vela (constellation)

Vela is a constellation in the southern sky. Its name is Latin for the sails of a ship, and it was originally part of a larger constellation, the ship Argo Navis, which was later divided into three parts, the others being Carina and Puppis.-Stars:...

. Its source supernova

Supernova

A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...

 exploded approximately 11,000-12,300 years ago (and was about 800 light years away). The association of the Vela supernova remnant with the Vela pulsar

Vela Pulsar

The Vela Pulsar is a radio, optical, X-ray and gamma-emitting pulsar associated with Vela Supernova Remnant, in the constellation of Vela.- Supernova origins :...

, made by astronomers at the University of Sydney

University of Sydney

The University of Sydney is a public university located in Sydney, New South Wales. The main campus spreads across the suburbs of Camperdown and Darlington on the southwestern outskirts of the Sydney CBD. Founded in 1850, it is the oldest university in Australia and Oceania...

 in 1968, was direct observational proof that supernovae form neutron stars.

The Vela supernova remnant includes NGC 2736

NGC 2736

NGC 2736 is called The Pencil Nebula. It is part of the Vela Supernova Remnant, located near the Vela Pulsar in the constellation Vela. The nebula's linear appearance triggered its popular name. It resides about 815 light-years away from our solar system. It is thought to formed from part of...

. It also overlaps the Puppis Supernova Remnant

Puppis A

Puppis A is a supernova remnant about 10 light-years in diameter. The supernova 'occurred' approximately 3700 years ago...

, which is four times more distant. Both the Puppis and Vela remnants are among the largest and brightest features in the x-ray sky

X-ray astronomy

X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects. X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and...

.

The Vela supernova remnant (SNR) is one of the closest known to us. The Geminga

Geminga

Geminga is a neutron star approximately 250 parsecs away from the Sun in the constellation Gemini. Its name is both a contraction of "Gemini gamma-ray source", and gh'è minga "it's not there" in the Lombard dialect of Milan .- Pulsar :...

 pulsar

Pulsar

A pulsar is a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation. The radiation can only be observed when the beam of emission is pointing towards the Earth. This is called the lighthouse effect and gives rise to the pulsed nature that gives pulsars their name...

 is closer (and also resulted from a supernova), and in 1998 another supernova remnant was discovered, RX J0852.0-4622

RX J0852.0-4622

RX J0852.0-4622 is a recently discovered supernova remnant. The remnant is located in the southern sky in the constellation Vela , and sits inside the much larger and older Vela Supernova Remnant...

, which from our point of view appears to be contained in the southeastern part of the Vela remnant. One estimate of its distance puts it only 200 parsec

Parsec

The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....

s away (about 650 ly

Light-year

A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...

), closer than the Vela remnant, and, surprisingly, it seems to have exploded much more recently (in the last thousand years or so) because it is still radiating gamma rays from the decay of titanium-44. This remnant was not seen earlier because in most wavelengths it is lost in the image of the Vela remnant.

External links

• http://antwrp.gsfc.nasa.gov/apod/ap960612.html
• http://www.aao.gov.au/images/captions/uks002.html
• http://antwrp.gsfc.nasa.gov/apod/ap970713.html
• http://astro.nineplanets.org/twn/velax.html
• http://antwrp.gsfc.nasa.gov/apod/ap070213.html
• Bill Blair's Vela supernova Remnant page
• http://www.skyfactory.org/vela/vela.htm