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etaha-2.jpg
etaha-2.jpgEta Carinae in HA.638 viewsThis stellar system is currently one of the most massive that can be studied in great detail. Until recently, Eta Carinae was thought to be the most massive single star, but it was recently demoted to a binary system.[7] The most massive star in the Eta Carinae multiple star system has more than 100 times the mass of the Sun. Other known massive stars are more luminous and more massive.

Stars in the mass class of Eta Carinae, with more than 100 times the mass of the Sun, produce more than a million times as much light as the Sun. They are quite rare — only a few dozen in a galaxy as big as the Milky Way. They are assumed to approach (or potentially exceed) the Eddington limit, i.e., the outward pressure of their radiation is almost strong enough to counteract gravity. Stars that are more than 120 solar masses exceed the theoretical Eddington limit, and their gravity is barely strong enough to hold in their radiation and gas.

Eta Carinae's chief significance for astrophysics is based on its giant eruption or supernova impostor event, which was observed around 1843. In a few years, Eta Carinae produced almost as much visible light as a supernova explosion, but it survived. Other supernova impostors have been seen in other galaxies, for example the false supernovae SN 1961v in NGC 1058[8] and SN 2006jc in UGC 4904,[9] which produced a false supernova, noted in October 2004. Significantly, SN 2006jc was destroyed in a supernova explosion two years later, observed on October 9, 2006.[10] The supernova impostor phenomenon may represent a surface instability[11] or a failed supernova. Eta Carinae's giant eruption was the prototype for this phenomenon, and after nearly 170 years the star's internal structure has not fully recovered.
Martin
IC443.jpg
IC443.jpgIC443.626 viewsIC 443 (also known as the Jellyfish Nebula and Sharpless 248 (Sh2-248)) is a Galactic supernova remnant (SNR) in the constellation Gemini. On the plan of the sky, it is located near the star Eta Geminorum. Its distance is roughly 5,000 light years (~5×1016 km) from Earth.
IC 443 is thought to be the remains of a supernova that occurred 3,000 - 30,000 years ago. The same supernova event likely created the neutron star CXOU J061705.3+222127, the collapsed remnant of the stellar core.
IC 443 is one of the best-studied cases of supernova remnants interacting with surrounding molecular clouds.
Martin
etacrop.jpg
etacrop.jpgEta Carinae nebula.610 viewsThis stellar system is currently one of the most massive that can be studied in great detail. Until recently, Eta Carinae was thought to be the most massive single star, but it was recently demoted to a binary system.[7] The most massive star in the Eta Carinae multiple star system has more than 100 times the mass of the Sun. Other known massive stars are more luminous and more massive.

Stars in the mass class of Eta Carinae, with more than 100 times the mass of the Sun, produce more than a million times as much light as the Sun. They are quite rare — only a few dozen in a galaxy as big as the Milky Way. They are assumed to approach (or potentially exceed) the Eddington limit, i.e., the outward pressure of their radiation is almost strong enough to counteract gravity. Stars that are more than 120 solar masses exceed the theoretical Eddington limit, and their gravity is barely strong enough to hold in their radiation and gas.

Eta Carinae's chief significance for astrophysics is based on its giant eruption or supernova impostor event, which was observed around 1843. In a few years, Eta Carinae produced almost as much visible light as a supernova explosion, but it survived. Other supernova impostors have been seen in other galaxies, for example the false supernovae SN 1961v in NGC 1058[8] and SN 2006jc in UGC 4904,[9] which produced a false supernova, noted in October 2004. Significantly, SN 2006jc was destroyed in a supernova explosion two years later, observed on October 9, 2006.[10] The supernova impostor phenomenon may represent a surface instability[11] or a failed supernova. Eta Carinae's giant eruption was the prototype for this phenomenon, and after nearly 170 years the star's internal structure has not fully recovered.
Martin
M45.jpg
M45.jpgM45.608 viewsIn astronomy, the Pleiades, or Seven Sisters (Messier object 45), is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky. Pleiades has several meanings in different cultures and traditions.

The cluster is dominated by hot blue and extremely luminous stars that have formed within the last 100 million years. Dust that forms a faint reflection nebulosity around the brightest stars was thought at first to be left over from the formation of the cluster (hence the alternate name Maia Nebula after the star Maia), but is now known to be an unrelated dust cloud in the interstellar medium that the stars are currently passing through. Astronomers estimate that the cluster will survive for about another 250 million years, after which it will disperse due to gravitational interactions with its galactic neighborhood.
Martin
Swan_done.jpg
Swan_done.jpgSwan nebula.606 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.
Martin
M42_570Kb.jpg
M42_570Kb.jpgM42.606 viewsQHY9 mono on ED80 and guided with a finderscope on a G11 with Gemini2
5 Minute LRGB with the core blended in with 30 second LRGB.
Martin
Eta_Carina.jpg
Eta_Carina.jpgEta Carinae599 viewstest image with OAG.Martin
chickenHA.jpg
chickenHA.jpgChicken nebula.597 viewsIC 2944, also known as the Running Chicken Nebula or the Lambda Cen Nebula, is an open cluster with an associated emission nebula found in the constellation Centaurus, near the star Lambda Centauri. It features Bok globules and is most likely a site of active star formation.

The Hubble Space Telescope image on the right is a close up of Bok Globules discovered in IC 2944 by South African astronomer A. David Thackeray in 1950[2]. These globules are now known as Thackeray's Globules.
Martin
Eagle_done-1.jpg
Eagle_done-1.jpgEagle nebula.588 viewsThe Eagle Nebula is part of a diffuse emission nebula, or H II region, which is catalogued as IC 4703. This region of active current star formation is about 6,500 light-years distant. The tower of gas that can be seen coming off the nebula is approximately 57 trillion miles (97 trillion km) high.

The brightest star in the nebula has an apparent magnitude of +8.24, easily visible with good binoculars.
Martin
snake-nebula.jpg
snake-nebula.jpgSnake nebula.584 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.
Martin
Eta_blue1Mb.jpg
Eta_blue1Mb.jpgEta Carinae578 views7X5 minute RGB and 7X10 minute LuminanceMartin
rosette_done_ha2Mb.jpg
rosette_done_ha2Mb.jpgRosetta in HA.566 viewsStill lots of noise in the surroundings so will need more exposures.Martin
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