Sawse - Stir it Up!

Two scientists who work for NASA have discovered the lightest black hole known to date. This lightweight black hole has a mass which is approximately 3.8 times more than the sun, and is only 15 miles in diameter. This particular black hole is approaching what is thought to be the minimum size that is needed for dying stars to become a black hole. Astronomers have been interested in and have been trying to discover what the minimum size required for a star to form a black hole is. This particular discovery may help to finally answer the burning question. Hiding in a binary star system in the Milky Way Galaxy, the black hole that has been named XTE J1650-500, is truly tiny in comparison to those that have been discovered so far. The binary star system where the black hole can be found, was discovered in 2001 by NASA’s Rossi X-ray Timing Explorer, or (RXTE) satellite. The fact that the J1650 contains a star and a small black hole, was realized fairly quickly after its discovery. However, the mass of the black hole had not been measured precisely at that point.

The two scientists, Shaposhnikov and Lev Titarchuk, gave a presentation in which they showed their findings at a meeting of the American Astronomical Society High Energy Astrophysics Divisions in Los Angeles. Titarchuk does not only work for NASA, he is also employed by George Mason University of Fairfax, as well as by the US Navel Research Laboratory which is located in Washington DC. The Astrophysics Journal has described the method that was used by the two scientists that lead to their discovery in several different papers. The method that they used relies on the connection between a black hole’s surrounding disks, and its inner part. It is from the surrounding disks where gases spiral inward toward the center of the black hole never to be seen again. When the rate slows to a medium pace, burning gasses gather close to the black hole and begin to radiate x-rays. The radiating x-rays vary in intensity and generally stick to a repeating pattern that occurs at regular intervals. This is known in the scientific community as a quasi-periodic oscillation (QPO).

For a while now, astronomers have theorized that the frequency of a QPO is related to the black hole’s mass. Titarchuk came to the conclusion in 19998, that the area of congestion is close to the center in small black holes, which means a higher frequency for the QPO. The larger the mass of a black hole the further out the congestion zone. This means that the cycles are running at a slower pace. Relying on data from archives on RXTE, Titarchuk and his colleague Shaposhnikov, were able to make very precise measurements of the frequencies of approximately fifteen other black holes’ QPO.

Black holes that had their masses measured by other means became of interest to the scientific duo, and they decided to apply their new technique. In the new test of black holes they produced 7 new results, of the seven three had already had masses that were thought to be measured with certainty.

There is a point in which a star that is dying should become a neutron star as apposed to a black hole. According to scientists, somewhere between 1.7 and 2.7 solar masses, is the commonly accepted boundary between what should become a black hole and what should develop into a neutron star. Where this dividing line truly lies is important in regard to the fundamentals of physics due to the fact that it will give scientists a firm idea of what happens to matter when it is compressed into super small proportions of very high density.

If future space travelers were to ever come across one of these tiny black monsters, they ought to be prepared. Surprisingly it is the smaller more black holes that produce stronger gravitational forces, in comparison to their larger cousins that can be found many times at the center of most galaxies. What would happen if a person were to get to close? Imagine your body being stretched into small strands that resemble spaghetti.

Astronomers may never succeed in finding the lightest black hole in the universe, but in results announced on March 31, they have come close. The Sun is a huge object and could contain more than a million Earths. So an object that is 3.8 Suns would sound like a lot. But it’s a pipsqueak when compared to all of the other known black holes. In the bizarre physics of black holes, time and space are exchanged when you cross an event horizon, but at the second horizon they would be switched back again.

If you ever did find yourself on your way into a black hole, you would encounter a very strange area in which space would be moving toward the center faster than light, at the core, space and light would then be back to normal. At the center of a black hole lays what is known as a singularity. The singularity has a really large appetite. It swallows matter of all shapes and sizes. If the situation were to arise where the singularity were consuming matter too quickly, matter would then start to collect and form into a dense hot plasma at the center of the black hole, and would then become part of the singularity.

Depending upon the size of the black hole, this plasma could prove to be the cause of a space traveler’s demise. Most books will tell you that under extreme gravitational conditions your feet would experience gravity more strongly than your head, and subsequently your body would be stretched into spaghetti like shape. While this might hold true for smaller black holes like our newfound friend, for super massive black holes weighing several millions or billions of suns, the tidal forces which cause the spaghetti effect are fairly weak. What would happen instead is that you would be burned by the plasma that can be found at the core.