Black Holes & Mira, the Wonderful Star

Ever since I heard what a Black Holes is I wanted to see one! Ever see that cheesy Disney movie from the 70's Blackhole? It fascinated me.


Since the creation of the Hubble Telescope it was only a matter of time before we got to see one. Buts whats that I hear you say? You cant see a blackhole because light cant esacpe from it? Well that is true; you might not be able to see the blackhole, but you can certainly see its passing!!

When a Blackhole passes close to a star, it starts to suck it in. The matter from the star streams towards the BH. As BH's are rotating the matter from the star starts to swirl around the event horizon of the BH just like a whirlpool. The gravity is so strong that the matter rotates close to the speed of light. They call this an accretion disc. You certainly can see those.

In fact the gravity is so strong that the BH sucks in far more matter than it can swallow. It ends up throwing out billions of tons of stellar matter from either pole. It throws them thousands of light years into space in two continuous jets.

Its not just BH's that create accretion disks. White Dwarf and Neutron stars do also. Both are the remains of collapsed stars that werent quite big enough to make a BH. The gravity they immit is still huge. A neutron star can have a diameter of 25k kilometres but have the gravity of a million Suns!!!

The last pictures are of Mira, the Wonderful Star, so called for its unusual fluctuations of brightness. Scientists now know Mira is a binary star system, with Mira A, a nice normal bright star, and Mira B, a White Dwarf star that is pulling huge amounts of solar matter from Mira A towards itself. The matter is spinning around Mira B at a huge speed kicking out emense amounts of radiaition. Radiaion is the main give-away for a BH.

The final picture is an artists recreation of what the Mira system might look like.


Nice.