5 Signs You Might Be Ready To Apply To Be An Astronaut

Black Holes are not so Black (Part 3) - Gravitational Waves

The existence of Gravitational Waves have been confirmed. But you probably have heard that. In this post, we will break down this profound discovery into comprehend-able chunks.

This is going to be a amazing journey. Ready ?

Redefining Gravity

When we usually talk of Gravitation we are bound to think like Newton, where objects are assumed to exerting a force upon each other.

Like imaginary arrows of force in space. But this picture, although good for high school crumbled, with the advent of Einstein’s theory of Relativity.

What is the Space-Time Fabric?

Think of space-time fabric as an actual cloth of fabric. ( An analogy )

When you place an object on the fabric, the cloth curves. This is exactly what happens in the solar system as well.

The sun with such a huge mass bends the space-time fabric. And the earth and all the planets are kept in orbit by following this curvature that has been made by the sun.

Attributing to the various masses of objects, the way they bend this fabric also varies.

What are Gravitational Waves?

If you drop an object in a medium such as water, they produce ripples that propagate as waves through the medium.

Similarly, Gravitational waves are ripples in space-time fabric produced when you drag heavy objects through space time.

And the nature of these waves is that they don’t require a medium to propagate.

How do you make one?

Everything with mass/energy can create these waves.

Source

Two persons dancing around each other in space too can create gravitational waves. But the waves would be extremely faint.

You need something big and massive accelerating through space-time in order to even detect them.

And orbiting binary stars/black holes are valuable in this retrospect.

How can you detect them?

Let’s turn to the problem to detecting them assuming you do find binary stars/black-holes in the wondrous space to suite your needs.

Well, for starters you cannot use rocks/ rulers to measure them because as the space expands and contracts, so do the rocks. ( the distances will remain same in both the cases )

Here’s where the high school fact that the speed of Light is a constant no matter what plays an important and pivotal role.

If the space expands, the time taken for light to reach from A to B would be longer. And if it contracts, the time taken for it to reach from A to B would be smaller.

PC: PHDComics

By allowing the light waves from the contraction and expansion to interfere with each other, such as done in any interferometry experiment we can detect the expansion or contraction. Voila!

And this is exactly what they did! ( on a macroscopic level ) at LIGO (Laser Interferometer Gravitational-Wave Observatory)

14 September 2015

Two Black Holes with masses of 29 and 36 solar masses merged together some 1.3 Billion light years away.

Two Black Holes colliding is the header animation of the ‘Black Holes are not so Black Series’, in case if you haven’t noticed.

The merger of these two black holes results in the emission of energy equivalent to 3 solar masses as Gravitational Waves.

This signal was seen by both LIGO detectors, in Livingston and Hanford, with a time difference of 7 milliseconds.

And with the measurement of this time difference, physicists have pronounced the existence of Gravitational Waves.

Source

All this is most certainly easily said than done and requires meticulous and extensive research, not to mention highly sensitive instruments.

Had they not have measured this time difference, we might have had to wait for the merger for more massive black holes to collide and maybe even build more sensitive instruments to detect these waves.

And Einstein predicted this a 100 years back!

Mind Blown!

Note: Hope you are able to understand and appreciate the profundity of the discovery done by mankind.

** All animations used here are merely for Educational purposes. If you have any issues, please write to us at : 153armstrong@gmail.com

Views of the Space Shuttle Atlantis undocking from the Mir space station on July 4, 1995. Cosmonauts Anotoliy Slovyev and Nikolai Budarin unparked the Soyuz spacecraft from Mir to perform a short fly-around when they snapped these astonishing photos. (NASA)

Gravitational Waves Exist: The Inside Story of How Scientists Finally Found Them

How a group of scientists proved Einstein right—and expanded our view of the universe.

M104, the Sombrero Galaxy

Credit: Jimmy Walker

Fun Moments with Our Record Breaking Astronaut

Astronaut Scott Kelly has broken the record for longest time spent in space by a U.S. astronaut. He has spent a cumulative of 383 days in space over the course of four missions. What better way to celebrate than to highlight some of his fun moments on the internet:

A question from the president during a recent TweetChat:

Astronaut Scott Kelly occasionally hosts TweetChats from the International Space Station. During a recent chat, he happened to get a question from someone who lives at 1600 Pennsylvania Avenue! HERE’s a recap from a similar chat from the station. 

Tackling the tough questions during interviews:

During an interview with Katie Couric, Kelly explained what a day on the space station is really like…including the chores he can and can’t do. 

The pros and cons of having roommates:

The International Space Station is an orbiting laboratory where an international crew live, work and conduct valuable research. 

Getting supplies from cargo ships:

Living on the space station requires food, water and supplies. All of these things, plus experiments and other essentials are delivered to the crew via cargo ship. Learn more about our commercial resupply program HERE. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

why am i sad

I don’t have any answer to this but I hope you feel better :’(  But here is a great example of astronomy and how awesome humanity can be

WHOA look at the moon

me literally every night no matter what phase the moon is in (via purple-space-freak)

أو كمَا يقُول أفلاطونٍ: “كُلّ الأشياءِ الجّميلة صعْبَة”.

“Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let them live. In a hundred billion galaxies, you will not find another.”   ~ Carl Sagan, Cosmos

“We used to look up at the sky and wonder at our place in the stars. Now we just look down, and worry about our place in the dirt.”