Skip to main content

Binary Black Hole






In early 2016, a group of scientists at LIGO observatory made an incredible announcement-detection of gravitational waves.  Gravitational waves are ripples in curvature of space-time. Till then, gravitational waves were considered as a theoretical concept.  This discovery is not momentous just because gravitational waves were discovered but also because nobody had ever seen two supermassive black holes orbiting so close to each other. This system is called Binary Black Hole (BBH).

BINARY BLACK HOLE:-

Binary black hole is a system which consists of two super massive black holes orbiting close to each other. Like ordinary black holes, BBH is also divided into stellar (black holes formed by gravitationalcollapse of a massive star) black holes. For many years, proving the existence of binary black hole was difficult because of nature of black holes itself and limited detection methods. When two black holes orbit close to each other, they give out immense amount of gravitational waves, in a specific waveform, that can be calculated by general relativity. All this was considered only as concept in 20th and early 21st century. It became a huge and interesting subject to study.

But all this became a history when a team of scientists at LIGO discovered gravitational waves. Since then a few group of astronomers have discovered more supermassive black holes pairs.  And now a group of scientist from Pune, India and Rochester Institute of Technology have discovered a pair which is closest. It is just 400 million light years away, in a galaxy named NGC 7674.

The study was led by Preeti Kharb, from the National Centre for Radio Astrophysics at Pune University in India and co-authored by Dharam Vir Lal, also at Pune University and Merritt at RIT.
Although the term “400 million light years” may seem a quite a large number, it is the closest pair ever discovered to our galaxy. Also, the pair of supermassive black holes each weighs more than a million times the mass of our sun. Hence considering this factors and how rare BBH are, they are big deal!

To add to this, these black holes are orbiting only one light year away apart from each other. Again, one light year is a big number for us but considering there masses; they are orbiting quite close to each other. Eventually they will get closer to each other and finally get merged. When this happens, strong gravitational signal will be created in outer space.

It is estimated that these two black holes will take another million years to collapse into each other and create a gravitational signal. Hopefully till then, someone will be still around to receive it!



Labels:

Comments

  1. TJ2 March 2018 at 15:22

    Amazing info for astro enthusiasts 🖖🖖

    ReplyDelete

Post a Comment

Popular posts from this blog

RETROGRADE AND PROGRADE

Since childhood we have learnt that all the planets go around the Sun. Meaning, the planets and other celestial objects rotate around the Sun in specific directions. But did you know that not all follow the same directions? Some follow the Sun’s rotation while some go in the opposite direction. After observing these motions of certain planets and comets, astronomers termed these rotations as “ Prograde ” and “ Retrograde ”. Before we get into these terms, let’s first understand how the direction of the motion is determined. The direction is determined by the primary object in system that forms the system’s hub. In our case, it is the Sun. So rotation of all the planets and celestial bodies is decided by the Sun’s direction of rotation. Now that we know how the motion is determined, let’s get into the above mentioned terms. Prograde:   It is the motion in the direction of that of the Sun. Meaning, most of the planets and some comets move in the direction of the ...
Post a Comment
Read more

Pluto-The controversial planet

Pluto has been our favorite planet since 2006. The reason why I wrote this blog is because NASA is ready to explore the planet and study it closely through its mission New Horizons. So before we get to know about this mission, let’s first get to know about Pluto. HISTORY: Pluto was discovered on February 18, 1930 in the Kuiper Belt. Kuiper belt is a ring of bodies beyond Neptune. Originally Pluto was considered as the ninth planet in solar system. But studying its size, mass, density etc. the International Astronomical Unit (IAU) defined the term “planet”. The definition goes as- “ planet  is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has cleared its neighbourhood" of smaller objects around its orbit.”   According to this definition, Pluto could not be classified as a planet and hence was reclassified as a “dwarf planet” in 2006. Although it is a dwarf planet compared to other eight planets, it is the second m...
2 comments
Read more

Cosmic Dawn

Looking in the universe is like looking through time. And this has led the astronomers from Arizona State University and MIT to find out about the time when the first stars light up-which was just 180 million years after the Big Bang. Astronomers call it the “Cosmic Dawn”. In early years, universe was in total darkness. This phase is generally referred to as the “Cosmic Dark Ages”. It was a phase when universe was a very cold and a very dark place. It consisted of only hydrogen gas, which made up the majority of the interstellar medium. Yet it was indistinguishable from all the cosmic radiation that was left behind by the Big Bang. But time passed and the matter started clustering together; it grew larger and exerted enough pressure to start nuclear fusion.   And this is how the first stars in our universe flickered!   The UV radiation emitted by these stars reacted with the hydrogen in the surrounding and it’s this reaction which was observed now! Diff...
Post a Comment
Read more