martinsastro

Astronomy for all.
Last additions - Martin
Daniel.jpg
Daniel.jpg435 viewsMartinNov 10, 2010
Big_Dave_and_John.jpg
Big_Dave_and_John.jpg514 viewsMartinNov 10, 2010
47Tucmoreblue2Gig.jpg
47Tucmoreblue2Gig.jpg47tuc518 viewsfor Trevor :)MartinNov 02, 2010
47Tucreprocessed2Gig.jpg
47Tucreprocessed2Gig.jpg47Tucanae2248 viewsThis is an reprocess and has an less green back ground, also the starcolors look better to me.MartinNov 02, 2010
47Tucdone2G.jpg
47Tucdone2G.jpg47Tucanae521 views47 Tucanae (NGC 104) or just 47 Tuc is a globular cluster located in the constellation Tucana. It is about 16,700 light years away from Earth, and 120 light years across. It can be seen with the naked eye, with a visual magnitude of 4.0. It's number comes not from the Flamsteed catalogue, but the more obscure 1801 "Allgemeine Beschreibung und Nachweisung der Gestirne nebst Verzeichniss" compiled by Johann Elert Bode.

47 Tucanae was discovered by Nicolas Louis de Lacaille in 1751, its southern location having hidden it from European observers until then. The cluster appears roughly the size of the full moon in the sky under ideal conditions.

It is the second brightest globular cluster in the sky (after Omega Centauri), and is noted for having a very bright and dense core. It has 23 known millisecond pulsars, and at least 21 blue stragglers near the core.
MartinOct 29, 2010
Tarantula-done.jpg
Tarantula-done.jpgTarantula nebula.781 viewsThe Tarantula Nebula (also known as 30 Doradus, or NGC 2070) is an H II region in the Large Magellanic Cloud. It was originally thought to be a star, but in 1751 Nicolas Louis de Lacaille recognized its nebular nature.

The Tarantula Nebula has an apparent magnitude of 8. Considering its distance of about 49 kpc[2] (160,000 light years), this is an extremely luminous non-stellar object. Its luminosity is so great that if it were as close to Earth as the Orion Nebula, the Tarantula Nebula would cast shadows. In fact, it is the most active starburst region known in the Local Group of galaxies. It is also the largest such region in the Local Group with an estimated diameter of 200 pc.[3] The nebula resides on the leading edge of the LMC, where ram pressure stripping, and the compression of the interstellar medium likely resulting from this, is at a maximum. At its core lies the compact star cluster R136 (approx diameter 35 light years)[4] that produces most of the energy that makes the nebula visible. The estimated mass of the cluster is 450,000 solar masses, suggesting it will likely become a globular cluster in the future.
MartinOct 28, 2010
NGC1097-done.jpg
NGC1097-done.jpgNGC1097.460 viewsNGC 1097 is a barred spiral galaxy about 45 million light-years away in the constellation Fornax. Three supernovae (SN 1992bd, SN 1999eu, & SN 2003B) have been observed in NGC 1097 (as of 2006).
Star forming ring in NGC 1097. HST. 0.9′ view

NGC 1097 is also a Seyfert galaxy, with jets shooting from the core. Like most galaxies, NGC 1097 has a supermassive black hole at its center. Around the central black hole is a ring of star-forming regions with a network of gas and dust that spirals from the ring to the black hole.
Colour-composite image of the central 5,500 light-years wide region of the spiral galaxy NGC 1097, obtained with the NACO adaptive optics on the VLT. Credit: ESO
Almost-true colour composite based on three images made with the multi-mode VIMOS instrument on the 8.2-m Melipal (Unit Telescope 3) of ESO's Very Large Telescope. Credit: ESO


NGC 1097 has two satellite galaxies. NGC 1097A is the larger of the two. It is a peculiar elliptical galaxy that orbits 42,000 light-years from the center of NGC 1097. NGC 1097B is the outermost one and not much is known about that.
MartinOct 28, 2010
Swan_done.jpg
Swan_done.jpgSwan nebula.568 viewsThe Omega Nebula, also known as the Swan Nebula and the Horseshoe Nebula[2] (catalogued as Messier 17 or M17 and as NGC 6618) is an H II region in the constellation Sagittarius. It was discovered by Philippe Loys de Chéseaux in 1745. Charles Messier catalogued it in 1764. It is located in the rich starfields of the Sagittarius area of the Milky Way.

The Omega Nebula is between 5,000 and 6,000 light-years from Earth and it spans some 15 light-years in diameter. The cloud of interstellar matter of which this nebula is a part is roughly 40 light-years in diameter. The total mass of the Omega Nebula is an estimated 800 solar masses.

A open cluster of 35 stars lies embedded in the nebulosity and causes the gases of the nebula to shine due to radiation from these hot, young stars.
MartinOct 19, 2010
snake-nebula.jpg
snake-nebula.jpgSnake nebula.546 viewsThe Snake Nebula (also known as Barnard 72) is a dark nebula in the Ophiuchus constellation. It is a small but readily apparent S-shaped dust lane that snakes out in front of the Milky Way star clouds from the north-north-west edge of the bowl of the Pipe Nebula. Its thickness runs between 2′ and 3′ and runs around 6′ in the north-west / south-east orientation. A good view in a 4" to 6" telescope requires clear dark skies.

It is part of the much larger Dark Horse Nebula.
MartinOct 19, 2010
rosettecropfinal.jpg
rosettecropfinal.jpgRosette nebula.510 viewsThe cluster and nebula lie at a distance of some 5,200 light years from Earth (although estimates of the distance vary considerably) and measure roughly 130 light years in diameter. The radiation from the young stars excite the atoms in the nebula, causing them to emit radiation themselves producing the emission nebula we see. The mass of the nebula is estimated to be around 10,000 solar masses.

It is believed that stellar winds from a group of O and B stars are exerting pressure on interstellar clouds to cause compression, followed by star formation in the nebula. This star formation is currently still ongoing.

A survey of the nebula with the Chandra X-ray Observatory in 2001 has revealed the presence of very hot, young stars at the core of the Rosette Nebula. These stars have heated the surrounding gas to a temperature in the order of 6 million kelvins causing them to emit copious amounts of X-rays.
MartinOct 19, 2010
ngc3293_3324.jpg
ngc3293_3324.jpgNGC3293 and 3324.462 viewsNGC 3293 is an open cluster in the Carina constellation. It was discovered by Abbe Lacaille in 1751-52. It consists of more than 50 stars in a 10 arc minutes field, the brightest of which is a red giant of mag 6.5.MartinOct 19, 2010
m42done.jpg
m42done.jpgM42.838 viewsThe Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated south of Orion's Belt. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of 1,344 ± 20 light years[2][5] and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. Older texts frequently referred to the Orion Nebula as the Great Nebula in Orion or the Great Orion Nebula.

The Orion Nebula is one of the most scrutinized and photographed objects in the night sky, and is among the most intensely studied celestial features.[6] The nebula has revealed much about the process of how stars and planetary systems are formed from collapsing clouds of gas and dust. Astronomers have directly observed protoplanetary disks, brown dwarfs, intense and turbulent motions of the gas, and the photo-ionizing effects of massive nearby stars in the nebula. There are also supersonic "bullets" of gas piercing the dense hydrogen clouds of the Orion Nebula. Each bullet is ten times the diameter of Pluto's orbit and tipped with iron atoms glowing bright blue. They were probably formed one thousand years ago from an unknown violent event.
MartinOct 19, 2010
132 files on 11 page(s) 9