Jedidah Isler: How I fell in love with quasars, blazars and our incredible universe

71,193 views ・ 2015-04-21

TED


Please double-click on the English subtitles below to play the video.

00:13
My first love was for the night sky.
0
13131
3301
00:16
Love is complicated.
1
16432
1566
00:17
You're looking at a fly-through of the Hubble Space Telescope Ultra-Deep Field,
2
17998
4529
00:22
one of the most distant images of our universe ever observed.
3
22527
4112
00:26
Everything you see here is a galaxy,
4
26639
2514
00:29
comprised of billions of stars each.
5
29153
3007
00:32
And the farthest galaxy is a trillion, trillion kilometers away.
6
32160
4741
00:37
As an astrophysicist, I have the awesome privilege of studying
7
37881
2924
00:40
some of the most exotic objects in our universe.
8
40805
3447
00:44
The objects that have captivated me from first crush throughout my career
9
44252
3812
00:48
are supermassive, hyperactive black holes.
10
48064
4409
00:53
Weighing one to 10 billion times the mass of our own sun,
11
53813
4118
00:57
these galactic black holes are devouring material,
12
57931
2894
01:00
at a rate of upwards of 1,000 times more
13
60825
3320
01:04
than your "average" supermassive black hole.
14
64145
3367
01:07
(Laughter)
15
67512
2128
01:09
These two characteristics,
16
69640
1694
01:11
with a few others, make them quasars.
17
71334
3214
01:14
At the same time, the objects I study
18
74548
2917
01:17
are producing some of the most powerful particle streams
19
77465
2777
01:20
ever observed.
20
80242
1695
01:21
These narrow streams, called jets,
21
81937
2840
01:24
are moving at 99.99 percent of the speed of light,
22
84777
4608
01:29
and are pointed directly at the Earth.
23
89385
3983
01:33
These jetted, Earth-pointed, hyperactive and supermassive black holes
24
93368
5889
01:39
are called blazars, or blazing quasars.
25
99257
4544
01:43
What makes blazars so special is that they're some of the universe's
26
103801
3481
01:47
most efficient particle accelerators,
27
107282
2520
01:49
transporting incredible amounts of energy throughout a galaxy.
28
109802
4918
01:54
Here, I'm showing an artist's conception of a blazar.
29
114720
2749
01:57
The dinner plate by which material falls onto the black hole
30
117469
3200
02:00
is called the accretion disc,
31
120669
1587
02:02
shown here in blue.
32
122256
1826
02:04
Some of that material is slingshotted around the black hole
33
124082
2979
02:07
and accelerated to insanely high speeds
34
127061
2024
02:09
in the jet, shown here in white.
35
129085
2827
02:11
Although the blazar system is rare,
36
131912
2687
02:14
the process by which nature pulls in material via a disk,
37
134599
3007
02:17
and then flings some of it out via a jet, is more common.
38
137606
3277
02:21
We'll eventually zoom out of the blazar system
39
141647
2444
02:24
to show its approximate relationship to the larger galactic context.
40
144091
5089
02:33
Beyond the cosmic accounting of what goes in to what goes out,
41
153890
4405
02:38
one of the hot topics in blazar astrophysics right now
42
158295
3047
02:41
is where the highest-energy jet emission comes from.
43
161342
3711
02:45
In this image, I'm interested in where this white blob forms
44
165053
3921
02:48
and if, as a result, there's any relationship between the jet
45
168974
3643
02:52
and the accretion disc material.
46
172617
2866
02:55
Clear answers to this question
47
175483
1803
02:57
were almost completely inaccessible until 2008,
48
177286
3115
03:00
when NASA launched a new telescope that better detects gamma ray light --
49
180401
4274
03:04
that is, light with energies a million times higher
50
184675
2712
03:07
than your standard x-ray scan.
51
187387
3547
03:10
I simultaneously compare variations between the gamma ray light data
52
190934
3890
03:14
and the visible light data from day to day and year to year,
53
194824
3669
03:18
to better localize these gamma ray blobs.
54
198493
3274
03:21
My research shows that in some instances,
55
201767
2686
03:24
these blobs form much closer to the black hole
56
204453
3060
03:27
than we initially thought.
57
207513
2360
03:29
As we more confidently localize
58
209873
1891
03:31
where these gamma ray blobs are forming,
59
211764
2296
03:34
we can better understand how jets are being accelerated,
60
214060
3523
03:37
and ultimately reveal the dynamic processes
61
217583
2608
03:40
by which some of the most fascinating objects in our universe are formed.
62
220191
4695
03:45
This all started as a love story.
63
225892
3609
03:49
And it still is.
64
229501
1913
03:51
This love transformed me from a curious, stargazing young girl
65
231414
4210
03:55
to a professional astrophysicist,
66
235624
1821
03:57
hot on the heels of celestial discovery.
67
237445
3337
04:00
Who knew that chasing after the universe
68
240782
2420
04:03
would ground me so deeply to my mission here on Earth.
69
243202
3798
04:07
Then again, when do we ever know where love's first flutter
70
247000
3468
04:10
will truly take us.
71
250468
1474
04:11
Thank you.
72
251942
1229
04:13
(Applause)
73
253171
3300
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7