Deep Sky Highlights – Sunday 18th January 2015

M1/NGC19523 The Crab – Supernova Remnant – An expanding cloud of dust from the explosion of a Supernova that was observed by the Japanese, Chinese in 1054 A.D. One of the brightest & conspicuous examples of a SN remnant. Back in 1054, the exploding star was so bright that it was visible during the daytime for several months. The Crab is located in the Constellation of Taurus. The cloud of dust is still expanding at about 1500KM per second. At the centre of the Crab is the collapsed core of the star that went supernova in 1054. This is now a Pulsar which is in fact a rapidly rotating and extraordinarily dense Neutron star, only a few KM in diameter and yet 1.4x the mass of our Sun, that emits a pulse of high energy X-ray radiation every 0.033 seconds as the Neutron star rotates at 30 times per second. The Crab is about 6 Light Years across and at a distance of 6,500 Light Years from Earth.

M1 The Crab

M1 The Crab

Below is a Hubble Space Telescope image of the Crab SN Remnant for comparison:

M1 - The Crab. Credit: Hubble/NASA

M1 – The Crab. Credit: Hubble/NASA

IC 434 The Horsehead Nebula – Slightly better resolved image (than last week) of the Horsehead Nebula in the Constellation of Orion. A Dark Nebula of dust silhouetted against the feint glow of Emission Nebula IC 434 behind.

 

The Horsehead

The Horsehead

Comet C/2014/Q2/Lovejoy – A visitor from the Oort Cloud in the outer Solar System and travelling at a speed of 133,000 Km per hour. Comet Lovejoy is known as a long period comet and it orbits the Sun once every 11,000 years. It comes closest to the Sun on 30th January at a distance of 1.3 Astronomical Units or 1.3 x the distance between the Sun and the Earth. It is currently about 95 Million KM from Earth and now passing through the Constellation of Aries.

Lovejoy is the brightest comet for some time at visual magnitude of about 5.0, just about visible in binoculars from London. Difficult to see in image below but I think a feint tail is detectable to the upper left of the comet’s head.

Comet C/2014/Lovejoy

Comet C/2014/Lovejoy

 

Deep Space……from the Orange Skies of Camberwell

The results of a brief real time video observing session last night.

First up is a very feint Horsehead Nebula in Orion. An impossible visible target from the light polluted skies of London but within reach with a 30sec video exposure using a Lodestar Colour camera and the free Lodestar Live software.

The Horsehead Nebula is one of the most famous nebulae on the sky. It is located to the south of Alnitak the Eastern of the 3 stars in Orion’s belt. This dark cloud of molecular dust is about 1500 Light Years from Earth.

The Horsehead shape is just about visible as the dark indentation to the red emission nebula behind. The Horsehead is dark because it is an opaque molecular dust cloud that lies in front of the bright red emission nebula. The Horsehead is a stellar nursery and within it many young stars are forming as the dust and gas coalesce through gravity and begin the process of star formation.

 

Horsehead Nebula Orion IC434

Horsehead Nebula Orion IC434

Next is the Great Nebula of Orion M42 is an emission and reflection nebula, illuminated by hot luminous stars emitting high energy ultra violet radiation. Located in the sword of Orion, M42 is the closest and most prominent star formation region to Earth (about 1500 light years distant). Again an area of massive star formation within immense molecular clouds of gas and dust with some 700 stars in various stages of star formation.  The nebula is about 30 light years across. The bright area at its very centre is a very young open cluster of stars known as the trapezium cluster. M42 is thought to contain the mass equivalent to 2000 Suns. The smaller M43 or Flame Nebula is to the upper right in the image below.

M42 The Great Orion Nebula

M42 The Great Orion Nebula

Click on the artist impressions below showing the location of the Orion Nebula in relation to our Sun/the Solar System and the rest of the Milky Way.

Orion Spur Credit Wikipedia

Credit:Wikipedia

Artists impression of Milky Way

Artists impression of Milky Way Credit Wikipedia

Lastly, Hubble’s Variable Nebula NGC 2261.

This peculiar object is located in the constellation of Monoceros, to the East of Orion. Discovered by W Herschel in 1783.

This is an emission and reflection nebula that is enveloping the erratic variable star R Monocerotis and is at a current visual Magnitude of 10.0. The variable nature of the brightness was first noted by Edwin Hubble in 1916 from a series of photographs. The unpredictable variation is thought to be due to shadows cast by the dense regions of dust passing by the star at its tip which cannot be seen directly and the light is only visible as the scattered light reflecting on dust particles in the surrounding molecular cloud.

Hubble’s Variable Nebula is about 3000 Light Years away. The cone shaped nebula is about 3 Light Years long and 1.5 Light Years across. The variable star R Mon is a very young star some 300,000 years old, of a mass of 10x our Sun  and has the illumination equivalent to 80x that of our Sun.

 

Hubble's Variable Nebula

Hubble’s Variable Nebula

For comparison is an image of the Hubble Variable Nebula taken using the Hubble Space Telescope:

Hubble Nebula using Hubble Space Telescope. Credit NASA

Hubble Nebula using Hubble Space Telescope. Credit NASA