ANDROMEDA (M31)
Processed and imaged in 2011
The Andromeda Galaxy (/ænˈdrɒmɨdə/) is a spiral galaxy approximately 2.5 million light-years (2.4×1019 km) from Earth in the Andromeda constellation. Also known as Messier 31, M31, or NGC 224, it is often referred to as the Great Andromeda Nebula in older texts. The Andromeda Galaxy is the nearest spiral galaxy to our Milky Way galaxy, but not the closest galaxy overall. It gets its name from the area of the sky in which it appears, the constellation of Andromeda, which was named after the mythological princess Andromeda. The Andromeda Galaxy is the largest galaxy of the Local Group, which also contains the Milky Way, the Triangulum Galaxy, and about 30 other smaller galaxies. Although the largest, the Andromeda Galaxy may not be the most massive, as recent findings suggest that the Milky Way contains more dark matter and could be the most massive in the grouping.[11] The 2006 observations by the Spitzer Space Telescope revealed that M31 contains one trillion (1012) stars:[8] at least twice the number of stars in the Milky Way galaxy, which is estimated to be 200–400 billion.[12]
The Andromeda Galaxy is estimated to be 7.1×1011 solar masses.[2] In comparison a 2009 study estimated that the Milky Way and M31 are about equal in mass,[13] while a 2006 study put the mass of the Milky Way at ~80% of the mass of the Andromeda Galaxy. The two galaxies are expected to collide in 3.75 billion years.[14]
At an apparent magnitude of 3.4, the Andromeda Galaxy is notable for being one of the brightest Messier objects,[15] making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope.
IMAGE DATA
4 x 900s 800 ISO LIGHT
6 x 900s 800 ISO DARK
0.41 arcsec / pixel
CRAB NEBULA (M1)
Processed and imaged in 2011
The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Arab, Chinese and Japanese astronomers in 1054. At X-ray and gamma-ray energies above 30 keV, the Crab is generally the strongest persistent source in the sky, with measured flux extending to above 1012 eV. Located at a distance of about 6,500 light-years (2 kpc) from Earth, the nebula has a diameter of 11 light years (3.4 pc) and expands at a rate of about 1,500 kilometers per second. It is part of the Perseus Arm of the Milky Way Galaxy.
At the center of the nebula lies the Crab Pulsar, a neutron star (or spinning ball of neutrons), 28–30 km across,[5] which emits pulses of radiation from gamma rays to radio waves with a spin rate of 30.2 times per second. The nebula was the first astronomical object identified with a historical supernova explosion.
The nebula acts as a source of radiation for studying celestial bodies that occult it. In the 1950s and 1960s, the Sun's corona was mapped from observations of the Crab's radio waves passing through it, and in 2003, the thickness of the atmosphere of Saturn's moon Titan was measured as it blocked out X-rays from the nebula.
The cloudy remnants of SN 1054 are now known as the Crab Nebula. The nebula is also referred to as Messier 1 or M1, being the first Messier Object catalogued in 1758.
IMAGE DATA
8 x Ha 900s - 7 x O3 900s
fov: 10,9 x 13,6 arcmin
scale: 1,11 arcsec/pixel
DUMBBELL NEBULA (M27)
Processed and imaged in 2011
The Dumbbell Nebula (also known as Apple Core Nebula, Messier 27, M 27, or NGC 6853) is a planetary nebula (PN) in the constellation Vulpecula, at a distance of about 1,360 light years.
This object was the first planetary nebula to be discovered; by Charles Messier in 1764. At its brightness of visual magnitude 7.5 and its diameter of about 8 arcminutes, it is easily visible in binoculars, and a popular observing target in amateur telescopes.
IMAGE DATA
5 x 1800s Ha - 4 x 1800s O3
1.11 arcsec / pixel
CRAB NEBULA (M1)
Processed and imaged in 2011
The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Arab, Chinese and Japanese astronomers in 1054. At X-ray and gamma-ray energies above 30 keV, the Crab is generally the strongest persistent source in the sky, with measured flux extending to above 1012 eV. Located at a distance of about 6,500 light-years (2 kpc) from Earth, the nebula has a diameter of 11 light years (3.4 pc) and expands at a rate of about 1,500 kilometers per second. It is part of the Perseus Arm of the Milky Way Galaxy.
IMAGE DATA
8 x 900s Ha - 4 x 1500s S2 - 7 x 900s O3
1.11 arcsec / pixel
CENTRE OF HEART NEBULA (IC 1805)
Processed and imaged in 2011
The Heart Nebula, IC 1805, Sh2-190, lies some 7500 light years away from Earth and is located in the Perseus Arm of the Galaxy in the constellation Cassiopeia. This is an emission nebula showing glowing gas and darker dust lanes. The nebula is formed by plasma of ionized hydrogen and free electrons.
The very brightest part of this nebula (the knot at the right) is separately classified as NGC 896, because it was the first part of this nebula to be discovered.
The nebula's intense red output and its configuration are driven by the radiation emanating from a small group of stars near the nebula's center. This open cluster of stars known as Melotte 15 contains a few bright stars nearly 50 times the mass of our Sun, and many more dim stars that are only a fraction of our Sun's mass. The cluster used to contain a microquasar that was expelled millions of years ago.
IMAGE DATA
0.41 arcsec / pixel
WIZARD NEBULA (NGC 7380)
Processed and imaged in 2011
NGC 7380 (also known as the Wizard Nebula) is an open cluster discovered by Caroline Herschel in 1787. William Herschel included his sister's discovery in his catalog, and labelled it H VIII.77. It is also known as 142 in the 1959 Sharpless catalog (Sh2-142). This reasonably large nebula is located in Cepheus.
IMAGE DATA
0.41 arcsec / pixel