Image Credit & Copyright: Travis Rector/University of Alaska Anchorage, H. Schweiker/WIYN & NOAO/AURA/NSF
Been a very busy week for me so my apologies on the slow rate of content but that being said this is still my 300th post of 2014 which is a milestone for me and this blogging stuff for a single year. Was hoping for one a day and there’s still time so we’ll see. Thanks for all the love and support everyone, you rock!
Like a mother holding up her newborn for pictures, reflection nebula NGC 1555 has seemingly opened her hand, revealing newborn star T Tauri to show it off to the universe and to also let it see the universe for the first time.
Truthfully, all personification aside that’s not too far from reality. What’s happening is that T Tauri, the reddish star partially shrouded in gas and dust hasn’t yet accreted enough material to where temperatures and pressures are high enough to spark nuclear fusion and render that star fully operational or main-sequence. Once that event takes place, the radiation and massive stellar winds immediately begin to clear out the surrounding area to include the thick cocoon of gas and dust that created it. For now, the energy we see in motion here is created by the continued effects of collapse and accretion.
There was also a nebula associated with this object. Observed in 1868 by Otto Wilhelm von Struve (yep the catalog guy) it was cataloged as NGC 1554 but later either vanished or wasn’t there at all. It would later become known as “Struve’s Lost Nebula.”
You may recognize T Tauri as an entire class of star and you would be correct. It’s the prototype and prominent member of the T Tau class of stars. These stars are pre-main sequence, variable newborns that have recently emerged from the shroud of material they were formed in. They are low mass stars that contain small amounts of lithium which by the time that the star goes main-sequence will have been destroyed.
These stars are usually accompanied by accretion disks which over time help the star continue to mature and likely leads to the formation of planets, asteroids, comets and eventually if they’re fortunate, life.
How does the accretion process of a star begin from a molecular cloud to begin with? Well, again just like real babies, it usually starts with some fireworks. Typically a nearby supernova occurs and when that happens, the resulting shockwave gives the local molecular cloud enough of a shove which then compresses the region in a process called Supernovae Induced Accretion.
NAME: T Tauri within reflection nebula NGC 1555 “Hind’s Variable Nebula.”
WHAT IS IT?: Newborn star and prototype of the T Tau class of variable stars.
HOW FAR AWAY IS IT?: Approximately 600 light years.
HOW BIG IS IT?: Less than 3 solar masses.
AGE?: Roughly 10 million years old.
DISCOVERER & DATE?: John Russell Hind in October of 1852.
APPARENT MAGNITUDE?: Variable from about 9.3 to 14.
WHERE IS IT? (General): Constellation Taurus near the Hyades open star cluster.
WHERE IS IT? (Exact RA/DEC J2000): RA 04h 21m 59.4s / DEC +19° 32′ 06.4”.
National Optical Astronomy Observatory (NOAO) page for this image: http://www.noao.edu/image_gallery/html/im1057.html
American Association of Variable Star Observers (AAVSO) page for this object: http://www.aavso.org/vsots_ttau