1
00:00:00,020 --> 00:00:04,080
[Music]

2
00:00:04,100 --> 00:00:08,090
Thanks to emissions powered by monster black holes, galaxies called

3
00:00:08,110 --> 00:00:12,130
blazars rank among the most luminous objects in the universe.

4
00:00:12,150 --> 00:00:16,190
They're also the most common sources of high-energy light seen by NASA's

5
00:00:16,210 --> 00:00:20,230
Fermi Gamma-ray Space Telescope.

6
00:00:20,250 --> 00:00:24,300
Like all active galaxies, a blazar gets its energy from matter

7
00:00:24,320 --> 00:00:28,420
falling toward a central supermassive black hole.

8
00:00:28,440 --> 00:00:32,570
A small part of this material forms particle jets that travel outward in

9
00:00:32,590 --> 00:00:36,750
opposite directions at near the speed of light. What makes blazars so

10
00:00:36,770 --> 00:00:40,760
intense is that we happen to be looking almost directly down the jet.

11
00:00:40,780 --> 00:00:44,820
Now, Fermi team members have identified five

12
00:00:44,840 --> 00:00:48,880
of the most distant gamma-ray blazars known.

13
00:00:48,900 --> 00:00:52,940
The record holder emitted its light when the universe was just one-tenth its current age.

14
00:00:52,960 --> 00:00:57,040
That object hosts a black hole with a mass of about 

15
00:00:57,060 --> 00:01:01,210
3 billion suns. That's 750 times bigger than 

16
00:01:01,230 --> 00:01:05,390
the black hole at the heart of our own galaxy. Another of these distant

17
00:01:05,410 --> 00:01:09,440
blazars boasts a black hole more than twice this size.

18
00:01:09,460 --> 00:01:13,610
In fact, the observed properties of all five of these blazars

19
00:01:13,630 --> 00:01:17,790
show they're the most extreme known members of this extreme

20
00:01:17,810 --> 00:01:21,830
galaxy class. The discovery makes it clear that

21
00:01:21,850 --> 00:01:25,870
enormous black holes formed very early in cosmic history,

22
00:01:25,890 --> 00:01:29,930
but astronomers aren't sure how. In general it's thought that

23
00:01:29,950 --> 00:01:33,990
large galaxies--and their black holes--were built up over time through a

24
00:01:34,010 --> 00:01:38,070
series of mergers with other smaller galaxies.

25
00:01:38,090 --> 00:01:42,170
It is unknown exactly how mergers can build a 

26
00:01:42,190 --> 00:01:46,280
billion-solar-mass black hole before the universe is much more than 

27
00:01:46,300 --> 00:01:50,420
one billion years old. But after netting five of these extreme blazars,

28
00:01:50,440 --> 00:01:54,440
researchers hope to find more of them in Fermi data.

29
00:01:54,460 --> 00:01:58,510
These objects allow scientists to map out how the most powerful jets in the universe

30
00:01:58,530 --> 00:02:02,690
evolved over cosmic time scales. And scientists hope

31
00:02:02,710 --> 00:02:06,750
that additional examples will help them better understand

32
00:02:06,770 --> 00:02:10,810
how supermassive black holes developed so rapidly in the early universe.

33
00:02:10,830 --> 00:02:14,860
[Music]

34
00:02:14,880 --> 00:02:18,890
[Music][Beeping]

35
00:02:18,910 --> 00:02:22,960
[Beeping]

36
00:02:22,980 --> 00:02:30,297
[Beeping]