Black Hole In Orion Nebula

The Orion Nebula is a familiar sight to amateur astronomers as one of the brightest gas clouds in the sky. Plus it is easy to find within one of the most prominent constellations, in the Sword of Orion.

The nebula, which appears as a swirling maelstrom through large telescopes, is a famous example of a cosmic nursery where new stars are being formed from gas and dust.

Now new research suggests that the nebula contains an intriguing extra component – a black hole with 200 times the mass of the Sun. A team of astronomers claims that this explains a mysterious force that binds a cluster of unruly, rapidly moving stars.

The nebula is the closest stellar birthplace to us at a distance of around 1,344 light-years. A black hole at such a close distance would offer a great opportunity to study such an object.

Hidden Black Hole. Current research suggests there may be a hidden intermediate sized black hole with a mass of 200 Suns here. This would explain the high velocity dispersion of stars within the cluster. So a few months from now, when you next point your telescope at the Orion nebula, pause for a moment to consider the amazing Trapezium. An international team of astrophysicists says the famous Orion Nebula has a black hole at its heart, whose mass is some 200 times the mass of our sun. One of the most recognized constellations is. The Horsehead is a dark nebula in the constellation Orion. Located just south of the star Alnitak, which is farthest east on Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex. The nebula was first recorded in 1888 by Scottish astronomer Williamina.

The cluster, whose four brightest stars are known as the Trapezium, has interested astronomers for a long time because the stars move at rapid speed as if they were flying apart.

And compared to the number of low-mass (light-weight) stars that can be seen in the cluster, the number of high-mass (heavy-weight) stars are too few and moving especially fast.

The discovery that a black hole is likely to be responsible for this erratic behaviour was made thanks to extensive computer modelling by the international team. The model, representing a tight cloud of inter-stellar gas containing the right combination of heavy and light stars, neatly explained what was being observed.

The study's lead author, Dr Ladislav Subr, of Charles University in Prague, said: 'In our model, we had to invent a new method of dealing with the gas and the way it is driven out from the cluster by the intensely radiating high-mass stars.

'Our scenario neatly accounts for virtually all observed properties of the Orion Nebula Cluster, that is, its low number of high-mass stars, and its rapidly-moving central stars, and suggests that the massive stars near the centre of this cluster are bound by a black hole.'

Team member Dr Holger Baumgardt, of Australia's University of Queensland, said such dense star cluster models were a challenge to compute due to the large number of calculations that had to be made.

The computations showed that, as the gas was being driven outwards, the cluster began to expand, explaining why most stars move rapidly.

Many of the heavy stars were sling-shot out of the cluster, while some were driven into the centre of the cluster and collided with the most massive star there.

At some point, this massive star became unstable and imploded into a black hole, with a mass about 200 times larger than the sun.

Constellation Orion Nebula

The team said that the finding had dramatic implications for our understanding of how massive stars form and how such rich star clusters hatch from their gaseous cocoons.

'Having such a massive black hole at our doorstep would be a dramatic chance for intense studies of these enigmatic objects,' said co-author Professor Pavel Kroupa from the University of Bonn in Germany. The study appears in The Astrophysical Journal.

Black Hole In Orion Nebula Images

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Orion Nebula Facts

Without a doubt the most beautiful nebula in the northern sky is the Great Nebula in Orion. Located 1500LY away, it's a favorite for stargazers and a common target for amateur astronomers from October to March.

You may know your way around a telescope, and think you know all about it. But in the heart of the nebula there is much more going on than meets the eye.

Find the familiar Orion constellation and look below the belt. Under dark skies, 2 or three stars, including a fuzzy cloud, should be visible. The fuzzy cloud is the Orion nebula, and inside it, the Trapezium.

Discovered by Galileo, the Trapezium is a tight grouping of stars in the center of the nebula. Responsible for much of the illumination of the nebula, the Trapezium appears at first glance to be 4 stars in the shape of a lopsided rectangle.

These visible stars are in fact just in front of a huge nebula that is teeming with over 2000 newborn stars.

Photo Of Black Hole In Orion Nebula

The brightest stars are labeled A-D, in order of right ascension. The brightest is Theta Orionis (C) at magnitude 5.1. A and B are eclipsing binaries, varying in brightness about 2.4x. This is a phenomenon easily detectable with an amateur telescope.

These hot stars produce so much high energy light, they ionize the surrounding hydrogen gas creating the visible Orion nebula. Theta Orionis is an O-type star, 251,000x brighter than our Sun, and one of the hottest stars in existence.

A casual glance reveals 4 bright stars in a little box. When viewed at magnifications > 125x, telescopes of 5' or more aperture under good seeing conditions may resolve two additional 11^th magnitude stars (E and F), for a total of six stars.

Larger instruments can pull in G and H under ideal conditions. I often use the challenge of spotting E and F with my TEC140 refractor as a test of seeing conditions.

It is a very young cluster of stars, only 300,000 years old. The dinosaurs never saw the Trapezium.

These stars are huge! The five brightest ones are 15-30x the mass of our Sun. And, they are all within 1.5 light years of each other. Can you imagine how bright they must appear from a point within the cluster?

Given that the lifespan of a star is inversely proportional to its mass, you can quickly calculate these 5 brightest stars each have less than a three million year lifespan. Soon, relatively speaking, they will each erupt into spectacular supernova explosions.
Our descendants will be able to see them in the daytime for a few months. Then in the years that follow spectacular new nebulae will be created. Perhaps by then we'll have FTL travel figured out and can have a ringside seat!

Current research suggests there may be a hidden intermediate sized black hole with a mass of ~200 Suns here. This would explain the high velocity dispersion of stars within the cluster.

So a few months from now, when you next point your telescope at the Orion nebula, pause for a moment to consider the amazing Trapezium. Given the age of the Earth and the size of the Milky Way, we are lucky to be here at the just the right time to enjoy it!

Black Hole In Orion Nebula

1. Cover Image (The Orion Nebula): Credit: Opo Terser. Licensed under the Creative CommonsAttribution 2.0 Generic license. https://commons.wikimedia.org/wiki/File:The_Great_Orion_Nebula_(M42).jpg
2. Trapezium, the center of the Orion Nebula. Credit: ESO/M.McCaughrean et al.
3. Trapezium. Credit: Mark Johnston