WEBVTT FILE

1
00:00:00.300 --> 00:00:03.704
NASA’s Hubble Space Telescope
has been watching a large, dark

2
00:00:03.704 --> 00:00:07.474
storm on the planet Neptune
disappear before our very eyes –

3
00:00:07.474 --> 00:00:11.812
or, telescope mirror. The first
and only spacecraft to visit

4
00:00:11.812 --> 00:00:17.518
Neptune was NASA’s Voyager 2 in
1989. It discovered two immense.

5
00:00:17.518 --> 00:00:20.187
dark storms churning through
Neptune’s thick, blue

6
00:00:20.187 --> 00:00:24.124
atmosphere. Voyager 2 then
headed out of the solar system,

7
00:00:24.124 --> 00:00:27.995
and since then our primary means
of watching Neptune’s storms has

8
00:00:27.995 --> 00:00:32.466
been the Hubble Space Telescope.
Our atmosphere on Earth makes it

9
00:00:32.466 --> 00:00:35.836
hard to look at blue light in
high resolution, so Hubble is

10
00:00:35.836 --> 00:00:38.739
currently the only telescope
that is able to see these

11
00:00:38.739 --> 00:00:43.076
storms. The larger of the two
storms Voyager 2 discovered on

12
00:00:43.076 --> 00:00:46.113
Neptune was called the Great
Dark Spot, because it looked

13
00:00:46.113 --> 00:00:49.049
very similar to the Great Red
Spot on Jupiter. Jupiter’s Great

14
00:00:49.049 --> 00:00:52.619
Red Spot has existed for
hundreds of years, but when

15
00:00:52.619 --> 00:00:56.857
Hubble looked at Neptune in
1994. the Great Dark Spot was

16
00:00:56.857 --> 00:01:00.027
already gone. Instead there was
a new storm on the northern

17
00:01:00.027 --> 00:01:04.097
hemisphere, which was named the
Northern Great Dark Spot. Since

18
00:01:04.097 --> 00:01:07.100
then, that spot has also
disappeared, and now in total

19
00:01:07.100 --> 00:01:10.837
we’ve observed five different
dark spots on Neptune. We can

20
00:01:10.837 --> 00:01:14.007
see that large storms on Neptune
form and dissipate much more

21
00:01:14.007 --> 00:01:17.477
rapidly than storms on Jupiter,
and there’s a lot of diversity

22
00:01:17.477 --> 00:01:20.247
in what Neptune’s storms look
like and how they move. These

23
00:01:20.247 --> 00:01:23.951
dark vortices on Neptune present
atmospheric scientists with an

24
00:01:23.951 --> 00:01:27.220
amazing opportunity to learn
about how storms work on a

25
00:01:27.220 --> 00:01:30.324
different world. But because
there is so much in the universe

26
00:01:30.324 --> 00:01:32.659
that Hubble looks at, the
telescope had only been

27
00:01:32.659 --> 00:01:36.296
observing Neptune once every few
years, which wasn’t frequent

28
00:01:36.296 --> 00:01:40.067
enough to watch the formation or
demise of any one particular

29
00:01:40.067 --> 00:01:43.503
storm. Since 2014 however,
Hubble has begun a project

30
00:01:43.503 --> 00:01:46.807
called the Outer Planet
Atmospheres Legacy program, or

31
00:01:46.807 --> 00:01:50.744
OPAL, to gather global maps of
our gas giant planets every year

32
00:01:50.744 --> 00:01:54.548
for the remainder of Hubble’s
operation. Now for the first

33
00:01:54.548 --> 00:01:58.618
time, using data from OPAL and
additional Hubble observations,

34
00:01:58.618 --> 00:02:02.255
Hubble has captured time-lapse
images showing the gradual death

35
00:02:02.255 --> 00:02:06.093
of a storm on Neptune. The
vortex pictured here is dredging

36
00:02:06.093 --> 00:02:09.329
up material from deep inside
Neptune’s atmosphere, possibly

37
00:02:09.329 --> 00:02:13.166
such as hydrogen sulfide, which
would make for a pretty smelly

38
00:02:13.166 --> 00:02:18.438
storm. In the first image from
2015. the storm is over 3000

39
00:02:18.438 --> 00:02:22.142
miles across – big enough to
stretch across the entire

40
00:02:22.142 --> 00:02:25.612
Atlantic Ocean from Boston to
Portugal. The storm is dark in

41
00:02:25.612 --> 00:02:28.382
blue wavelengths, but
overshadowed at green and red

42
00:02:28.382 --> 00:02:32.285
wavelengths by nearby companion
clouds. The contrast of the dark

43
00:02:32.285 --> 00:02:35.989
vortex faded quite a bit by late
2017. though the feature was

44
00:02:35.989 --> 00:02:40.360
still over 2000 miles wide.
Seeing this storm unfold gives

45
00:02:40.360 --> 00:02:43.697
scientists a chance to test
their models of how they

46
00:02:43.697 --> 00:02:47.067
predicted an anticyclone may
interact with the wind jets on

47
00:02:47.067 --> 00:02:50.137
Neptune. This particular vortex
is not behaving how some

48
00:02:50.137 --> 00:02:53.540
dynamical simulations predicted,
which is great because that

49
00:02:53.540 --> 00:02:57.344
means there’s a lot left to
learn on Neptune. The Hubble

50
00:02:57.344 --> 00:03:00.647
Space Telescope is up to that
task of advancing scientists’

51
00:03:00.647 --> 00:03:03.884
understanding of planetary
atmospheres.

52
00:03:03.884 --> 00:00:00.000
www. nasa. gov/hubble
@NASAHubble