May
20
Hat tip to this headline writer.
(via rubenfeld)
notes of the universe
He met Bill Murray.
Submitted by: Laura R.
Location: St. Andrew’s, Scotland
(via pushthemovement)
Question: If 2 black holes get near each other, can they then gravitationally pull matter out of the other black hole & back into “normal” space?
The short answer is no.
A black hole (in the traditional sense) is defined as an object that has collapsed so that its radius is equal to, or less than, the Schwarzschild of the object.
What does this mean?
Every object has a Schwarzschild radius; this is the point at which an object’s mass is so compressed that the gravitational influence overpowers the other forces of nature and it collapses to a singularity.
Of course, not every object is massive enough to collapse to its Schwarzschild radius. The Earth’s Schwarzschild radius, for example, is about the diameter of a small marble. If you were to apply enough energy to the Earth and compress its mass to that size, it would collapse to form a black hole. The same is true for humans, except I’d need to compress you to a point some 10-million times smaller than a marble in order to turn you into a black hole.
So, what is special about the Schwarzschild radius? This is the point at which the escape velocity for the object is equal to the speed of light. Obviously, since you can’t travel ,or faster than, the speed of light you can’t get out of a black hole neither can another black hole pull you out.
It’s important to realize that, outside of the Schwarzschild radius (also known as the event horizon), spacetime is normal. You can interact with a black hole in the same ways you interact with any other object of mass.
Image credit: NASA/CXC/A.Hobart
(via darylelockhart)
Underwater photography by Hengki Koentjoro.
(via everydayfrustone)
May
14
False Alarm of the Day: FBI Questions Saudi Student for Possession of a Pressure Cooker
Last Friday, the FBI surrounded the home of Saudi student Talal al Rouki after his neighbor tipped off the authorities that he has been seen around the residential area with a pressure cooker, a household kitchenware that recently made the headlines after it was used by the Boston Marathon terrorists to set their deadly bombs off in April. When questioned by the FBI, the frightened Michigan resident showed FBI agents the cooking apparatus, informing them he had used it to make the Saudi Arabian rice dish kabsah before taking it over to a friend’s house, to which they replied “You need to be more careful moving around with such things, Sir.” …Welcome to ‘Murica, Talal!
Teenagers’ queue at a ticket window in West Hartford, Connecticut, 1954. Photo by Yale Joel.
