"In the sky above and around it you can see Venus (lower right), Mercury (upper right), and mighty Jupiter (to the left). All three are unresolved dots at this magnification, but they may look different sizes because of their varying brightnesses. If the size variation were real, Jupiter would look three times bigger than Venus, and five times bigger than Mercury in the picture! Currently, all three are on the other side of the Sun, making them appear smaller than they can be. Mercury is actually the closest right now, about 170 million kilometers (105 million miles) distant, compared to 250 million km (150 million miles) for Venus and 910 million km (565 million miles) for Jupiter."
via Bad Astronomy
An incredible site to see in the sky.
Earth From Space: Antarctica’s Secrets continued…
I’m sorry, did he just say “the size of 500 Niagara Falls” ?!?
Earth From Space: Antarctica’s Secrets
Who knew Antarctica played such a key role in supporting all life on Earth? These visuals are stunning!
Earth From Space: Part 2
The Earth is forever seeking an equilibrium that it never can reach. This segment explains the Monsoon of Western India and a place where no rainfall has ever been recorded!
Earth from Space
How the World works as seen from space. This first segment shows how the world’s moisture plays a key role in keeping Earth’s oceans at equilibrium via massive hurricanes and other intricate systems.
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
Article: From Quarks to Quasars
Cool facts about black holes and how compressed a human has to be to form one.
Next time you see the Sun, please tell it that size doesn’t matter. But, woah!
If you have ever wondered what a decommissioned satellite looks like when it burns up in Earth’s atmopshere, look no further!
Repairing the Station in Orbit
Expedition 35 Flight Engineers Chris Cassidy (pictured) and Tom Marshburn (out of frame) completed a spacewalk at 2:14 p.m. EDT May 11, 2013 to inspect and replace a pump controller box on the International Space Station’s far port truss (P6) leaking ammonia coolant. The two NASA astronauts began the 5-hour, 30-minute spacewalk at 8:44 a.m.
A leak of ammonia coolant from the area near or at the location of a Pump and Flow Control Subassembly was detected on Thursday, May 9, prompting engineers and flight controllers to begin plans to support the spacewalk. The device contains the mechanical systems that drive the cooling functions for the port truss.
Image Credit: NASA
Milky Way vs. City Lights – My first attempt at computational astrophotography
From Mount Wilson on a moonless night, the Milky Way is faintly visible over Los Angeles. I wanted to see if I could extract enough information from multiple exposures to overcome the city lights and make the Milky Way become conspicuous.
This picture is the result of a fair amount of mathematical modeling and processing. All of the shots used to produce this image are taken from the same spot without moving the camera between exposures. I’ve included some further explanation and intermediate images in the first comment below.
- Aaron Kiely