Black holes???

Black holes???

According to the scientists,our Universe is expanding every second .There are number of mysteries present in the universe. 

And one of the most mysterious object is the 

"BLACK HOLES".

According to NASA :

They’re huge concentrations of matter packed into very tiny spaces.A black hole is so dense that gravity just beneath its surface, the event horizon, is strong enough that nothing – not even light – can escape. The event horizon isn’t a surface like Earth’s or even the Sun’s. It’s a boundary that contains all the matter that makes up the black hole.

Formation of black holes??

Now lets talk about how these massive matter of the space actually form!

 Here i want to share a pic that easily manifests the formation of these black holes

So as you see this picture how black holes come in to being.

The two neutron stars also revolve with so much energy and forms a massive black hole.

Parts of black holes:

Acc. to NASA,

Black holes consists of following parts:

• Accretion disk : 

the extreme gravity of a Black Hole attracts matter around it - gas, interstellar matter, rocks, planets, and sometimes other stars. The matter falling onto the black hole creates an accretion disk, where, heated by friction to the point of shining far brighter than a typical star.

• Binary system :

 some stars are entrapped in a binary system with a black hole, not another star.

• Galaxy core :astronomical observations show that nearly every galaxy has a supermassive black hole at its center. Sagittarius A*, a supermassive Black Hole at the center of the Milky Way Galaxy, can be detected with active radio emissions from its accretion disk

• Jets - massive objects like black holes, neutron stars, and pulsars tend to emit a shot of ionized matter along their axis of rotation, sometimes extending for thousands of light-years in length. Jets are shiny and relatively easy to observe.

Gravitational lensing:

A great phenomenon of showcasing the why light can not pass in to the black holes ?

Answer is the gravitational lensing

Massive objects like black holes can bend and distort light from more distant objects. This effect, called gravitational lensing, can be used to find isolated black holes that are otherwise invisible

The first detected black hole was Cygnus-X1

Types of black holes:

Supermassive black holes
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Acc. to Wikipedia 

• 1ES 2344+514
• Ton 618 (this quasar has possibly the biggest black hole ever found, estimated at 66 billion solar masses)^[1]
• 3C 371
• 4C +37.11 (this radio galaxy is believed to have binary supermassive black holes)^[2]
• AP Lib
• S5 0014+81 (said to be a compact hyperluminous quasar, estimated at 40 billion solar masses)^[3]
• APM 08279+5255 (contains one of the largest black holes, estimated at 10-23 billion solar masses; previous candidate for largest)^[4][5]
• Arp 220
• Centaurus A
• Fornax A
• HE0450-2958
• IC 1459
• Messier 31 (or the Andromeda Galaxy)
• Messier 32
• Messier 51 (or the Whirlpool Galaxy)
• Messier 60
• Messier 77
• Messier 81 (or Bode's Galaxy)
• Messier 84
• Messier 87 (or Virgo A)
• Messier 104 (or the Sombrero Galaxy)
• Messier 105
• Messier 106
• Mrk 421
• Mrk 501
• NGC 821
• NGC 1023
• NGC 1097
• NGC 1271
• NGC 1277
• NGC 1332
• NGC 1566
• NGC 2787
• NGC 3079
• NGC 3115
• NGC 3377
• NGC 3384
• NGC 3998
• NGC 4151
• NGC 4261
• NGC 4438
• NGC 4459
• NGC 4473
• NGC 4486B (a satellite galaxy of Messier 87)^[6]
• NGC 4564
• NGC 4579
• NGC 4596
• NGC 4697
• NGC 4889
• NGC 4945
• NGC 5033
• NGC 6251
• NGC 7052
• NGC 7314
• PKS 0521-365
• Q0906+6930 (a blazar organized around a supermassive black hole)^[7]
• RX J1131 (first black hole whose spin was directly measured)^[8]
• Sagittarius A*, which is in the center of the Milky Way

• Intermediate-mass black hole:

• Cigar Galaxy (Messier 82, NGC 3034)
• GCIRS 13E
• HLX-1
• M82 X-1
• Messier 15 (NGC 7078)
• Messier 110 (NGC 205)
• Sculptor Galaxy (NGC 253)
• Triangulum Galaxy (Messier 33, NGC 598)

Stellar black holes:

• 1E1740.7-2942 (Great Annihilator), 340 ly from Sgr A*[9]
• 4U 1543-475/IL Lupi
• A0620-00/V616 Mon (once thought to be the closest to Earth known, at about 3,000 light years)[10]
• CXOU J132527.6-430023 (a candidate stellar mass black hole outside of the Local Group)[11]
• Cygnus X-1
• Cygnus X-3
• GRO J0422+32 (possibly the smallest black hole yet discovered)[12]
• GRO J1655-40/V1033 Sco (at one time considered the smallest black hole known)[13]
• GRS 1124-683/GU Mus
• GRS 1915+105/V1487 Aql
• GS 2000+25/QZ Vul
• GX 339-4/V821 Ara
• IGR J17091-3624 (candidate smallest known stellar black hole)[14][15]
• LB-1 (name of both a galactic B-type star and a very closely associated over-massive stellar-mass black hole)[16][17]
• M33 X-7 (stellar black hole with the most massive stellar companion, located in the Triangulum Galaxy)[18]
• MOA-2011-BLG-191/OGLE-2011-BLG-0462 (first known isolated stellar black hole)
• SN 1997D (in NGC 1536)
• SS 433
• V404 Cyg
• V Puppis
• XTE J1118+480/KV UMa
• XTE J1550-564/V381 Nor
• XTE J1650-500 (at one time considered the smallest black hole known)[13]
• XTE J1819-254/V4641 Sgr
• LMC X-1 (first X-ray source in the Large Magellanic Cloud)

As of February 2019, 10 mergers of binary black holes have been observed. In each case two black holes merged to a larger black hole. In addition, one neutron star merger has been observed (GW170817), forming a black hole. In addition, over 30 alerts have been issued since April 2019, of black hole merger candidates.