Einstein presented his theory of relativity in 1916, but for an entire century nobody could find physical proof of black holes. In 2016, scientists finally detected gravitational waves that emitted from 2 black holes colliding, proving that such things not only exist, but that Einstein was right all along. Source
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 ?
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.
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.
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.
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.
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)
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.
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 : [email protected]
As our Cassini spacecraft enters its final 20 months before its plunge into Saturn, the mission’s science team has selected their top 10 images from 2015 (above), a year of historic discoveries, as well as the top science results (below). Take a look:
1. First Deep Seafloor Hydrothermal Vents Found Beyond Earth
Cassini found the first evidence of active hot-water chemistry beyond planet Earth. An extensive, four-year analysis of data from the spacecraft, computer simulations and laboratory experiments led researchers to the conclusion the tiny silica (SiCO2) grains most likely form when hot water containing dissolved minerals from the moon’s rocky interior travels upward, coming into contact with cooler water.
2. Global Ocean Beneath Enceladus’ Surface
A global ocean lies beneath the icy crust of Saturn’s geologically active moon Enceladus. Scientists analyzed more than seven years’ worth of images of Enceladus taken by the spacecraft, which has been orbiting Saturn since mid-2004. As a result, they found Enceladus has a tiny, but measurable wobble as it orbits Saturn. This proves that there must be a global layer of liquid separating the surface from the core.
3. Titan Observed Outside of Saturnian Magnetosphere
During Cassini’s flyby of Titan, the giant moon happened to be on the sunward side of Saturn when a powerful outburst of solar activity reached the planet. The strong surge in the solar wind so compressed the sun-facing side of Saturn’s magnetosphere that the bubble’s outer edge was pushed inside the orbit of Titan. This left the moon exposed to, and unprotected from, the raging stream of energetic solar particles. The region of space dominated by Saturn’s magnetic field is called the magnetosphere.
4. Density of a Ring Particles May Indicate Recent Origins
Saturn’s A ring was found to be warmer than expected at the planet’s equinox, and also had an unusually large thermal asymmetry about the equinox. This could be due to the A ring being mostly composed of denser particles made primarily of solid ice, with a thin top layer of fluffy regolith.
5. Titan Southern Polar Ice Cloud
Scientists have detected a monstrous new cloud of frozen compounds in Titan’s low- to mid-stratosphere – a stable atmospheric region above the troposphere, or active weather layer.
6. Curtain Vents on Enceladus?
New research using data from Cassini suggests most of the eruptions from Saturn’s moon Enceladus might actually be diffuse curtains rather than discrete jets. Many features that appear to be individuals jets of material erupting along the length of prominent “tiger stripe” fractures in the moon’s south polar region might be phantoms created by an optical illusion, according to the new study.
7. Discovery of Tethys Red Arcs
Like graffiti sprayed by an unknown artist, unexplained arc-shaped, reddish streaks are visible on the surface of Saturn’s icy moon Tethys. The origin of the features and their reddish color is a mystery to scientists.
8. Saturn’s 30-year Giant Storms Powered by Water Convection
Changes in temperature and the composition of the hydrogen-laden air within the remnants of a giant storm system on Saturn reveal that air was lofted more than 120 miles in altitude from the deeper water condensation levels.
9. Seasonal Change Seen at Saturn’s Poles
Saturn’s polar regions have displayed extreme seasonal changes during Cassini’s decade-long watch, providing the most comprehensive view ever obtained of seasonal change on a giant planet.
10. Huygens Probe Imaging Mosaic of Titan’s Surface and Descent Movie
Ten years ago, an explorer from Earth, the Huygens probe, was released from the Cassini spacecraft and parachuted into the haze of an alien moon toward an uncertain fate. After a gentle descent lasting more than two hours, it landed with a thud on a frigid floodplain on Titan, surrounded by icy cobblestones.
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Here are a few things you should know about our solar system this week:
1. The Bright and the Beautiful
In its lowest-altitude mapping orbit, at a distance of 240 miles (385 kilometers) from Ceres, Dawn has provided scientists with spectacular views of the dwarf planet, especially of its bright, young, hexagonal craters like Haulani.
2. Mars Needs Brains
NASA is soliciting ideas from U.S. industry for designs of a Mars orbiter for potential launch in the 2020s. The satellite would provide advanced communications and imaging, as well as robotic science exploration, in support of NASA’s Journey to Mars. This effort seeks to take advantage of industry capabilities to improve deep space, solar electric propulsion-enabled orbiters.
3. Seeing Double
NASA measured a solar flare from two different spots in space, using three solar observatories. During a December 2013 solar flare, three sun-observing spacecraft captured the most comprehensive observations ever of an electromagnetic phenomenon called a current sheet.
4. Set a Course for Europa
This artist’s rendering shows NASA’s Europa mission spacecraft, which is being developed for a launch in the 2020s. The mission would place a spacecraft in orbit around Jupiter in order to perform a detailed investigation of the giant planet’s moon Europa—a world that shows strong evidence for an ocean of liquid water beneath its icy crust and which could host conditions favorable for life.
5. Go Deep
Jupiter is huge, powerful and spectacular. But what lies hidden inside the giant planet? The Juno mission arrives at Jupiter in July to help us find out. Join Dr. Fran Bagenal to learn more about the mission and how it plans to delve deep into Jupiter’s secrets this year.
Want to learn more? Read our full list of things to know this week about the solar system HERE.
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Once again, Albert Einstein is proven right. Read more about this discovery in The Guardian.
tell the moon i love her
Dear moon, @324b2dun loves you. Happy Valentines!
Southern Cross by Carlos Fairbairn
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Dark, cold and whipped by supersonic winds, Neptune is the last of the hydrogen and helium gas giants in our solar system. More than 30 times as far from the sun as Earth, the planet takes almost 165 Earth years to orbit our sun! In fact, in 2011, Neptune completed its first orbit since its discovery in 1846.
Here are a few things you might not know about the windiest planet:
If the sun were as tell as a typical front door, the Earth would be the size of a nickel and Neptune would be about as big as a baseball.
Neptune orbits our sun, a star. Neptune is the eighth planet from the sun at a distance of about 4.5 billion km (2.8 billion miles) or 30.07 AU.
One day on Neptune takes about 16 hours (the time it takes for Neptune to rotate or spin once)
Neptune makes a complete orbit around the sun (a year in Neptunian time) in about 165 Earth years (60,190 Earth days)
Neptune has six rings
Voyager 2 is the only spacecraft to have visited Neptune
Neptune has 13 moons. They are named after various sea gods and nymphs in Greek mythology
Did you know that Neptune has storms?
Similar to Jupiter, Neptune has storms that create gigantic spots in its atmosphere…well, it did. When Voyager 2 flew past Neptune in 1989, it tracked and imaged the “Great Dark Spot” — a storm larger than the entire Earth! When the Hubble Space Telescope imaged Neptune the spot had disappeared, only to be replaced with two smaller storms, which in turn also disappeared.
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"Astronomy compels the soul to look upwards and leads us from this world to another." - Plato
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