WEBVTT FILE

1
00:00:00.000 --> 00:00:07.340
[music throughout] A historic moment is on the horizon for NASA’s OSIRIS-REx mission

2
00:00:07.340 --> 00:00:13.580
On October 20, the OSIRIS-REx spacecraft will journey to asteroid Bennu’s

3
00:00:13.580 --> 00:00:16.683
Bennu’s boulder-strewn surface and briefly touchdown to gather a sample –

4
00:00:16.683 --> 00:00:20.487
something NASA has never done before.

5
00:00:20.487 --> 00:00:25.625
Right now, you are watching OSIRIS-REx preparing for its descent

6
00:00:25.625 --> 00:00:31.998
to sample site Nightingale, a dark crater near Bennu’s north pole, that you can see below you now.

7
00:00:31.998 --> 00:00:38.071
Site Nightingale is one of the only areas on Bennu that holds

8
00:00:38.071 --> 00:00:41.808
enough fine-grained material for the spacecraft to safely access.

9
00:00:41.808 --> 00:00:47.247
The crater is only 66 ft (20 meters) in diameter, or about the size of a tennis court

10
00:00:47.247 --> 00:00:54.087
The Nightingale site itself is only 26 ft (8 m) wide, nearly the width of 3 parking spaces.

11
00:00:54.087 --> 00:00:59.492
From orbit departure, to the steep descent, to the back-away burn,

12
00:00:59.492 --> 00:01:04.697
the spacecraft will perform the entire sample collection sequence autonomously.

13
00:01:04.697 --> 00:01:10.937
To safely touch the site, the spacecraft has to position itself for the Touch-And-Go sample collection maneuver.

14
00:01:10.937 --> 00:01:16.810
OSIRIS-REx will first stretch out its sampling arm from the folded, parked position.

15
00:01:16.810 --> 00:01:23.883
Then, it will slowly move its solar panels into the “Y-wing” configuration – as you see right now.

16
00:01:23.883 --> 00:01:27.720
Placing the solar panels up and away from the asteroid’s surface during touchdown.

17
00:01:27.720 --> 00:01:34.527
This configuration also places the spacecraft’s center of gravity directly over the TAGSAM collector head,

18
00:01:34.527 --> 00:01:39.699
which is the only part of the spacecraft that will contact Bennu’s surface during the sample collection event.

19
00:01:39.699 --> 00:01:48.775
As OSIRIS-REx descends to Nightingale, it will approach the site and fly over building-sized boulders scattered around the crater’s rim.

20
00:01:48.775 --> 00:01:53.780
The tallest one you see is about the same height as a three-story building.

21
00:01:53.780 --> 00:02:00.487
The spacecraft will spend approximately 22 minutes deeply descending to the rocky surface…

22
00:02:00.487 --> 00:02:16.202
While OSIRIS-REx descends, take a look around sample site Nightingale.

23
00:02:16.202 --> 00:02:21.107
Remember, OSIRIS-REx is aiming to tag a spot no larger than a few parking spaces.

24
00:02:21.107 --> 00:02:26.179
In between these boulders are small patches of relatively clear surface –

25
00:02:26.179 --> 00:02:32.051
enough to allow OSIRIS-REx to collect at least 60 grams of pristine asteroid sample.

26
00:02:32.051 --> 00:02:37.390
With just meters to go, OSIRIS-REx is now ready to collect a sample.

27
00:02:37.390 --> 00:02:44.998
Once the sample collector head senses contact with Bennu’s surface, it will fire a small puff of compressed nitrogen

28
00:02:44.998 --> 00:02:53.006
to kick up debris and capture pieces of the asteroid into the collector head – an event that lasts just a few seconds.

29
00:02:53.006 --> 00:03:05.985
OSIRIS-REx will then fire its thrusters to slowly back-away from the surface and navigate to a safe distance away from Bennu.

30
00:03:14.994 --> 00:03:23.903
A couple days later, the spacecraft will image the inside of the sample collector head to verify that material was collected.

31
00:03:23.903 --> 00:03:29.542
The sample will be delivered to Earth in September 2023.