Chapter 2 of 5

A picture and a stuck pin

Seeing the landing site and repairing a sampler from Earth

Told in Viking 1’s imagined voice · the events are real · source

Sunset at the Viking Lander 1 Site
Viking 1My first view was built one strip at a time.
NASA/JPL
01My facsimile camera scanned the scene rather than snapping it all at once. The first photograph shows rocks, fine material and part of footpad two. Later color images added another view. Scientists used calibration targets to interpret images, not just to make Mars look familiar.
Two instruments needed help. One would never get it.
02My seismometer failed to unlock from its travel restraint, so it could not carry out its intended measurements. My sampler had a different problem: a locking pin was stuck. Without a working scoop, the soil experiments could not receive their samples.
Viking Lander 1 Thomas A.
Viking 1My team tried the repair on Earth before asking me to try it on Mars.
NASA/JPL-Caltech/University of Arizona
03Engineers tested carefully planned commands on a duplicate lander. My cameras helped them check progress remotely. The sampler was freed, and images showed the troublesome pin on the ground. A repair across space needed evidence and testing, not a bigger shove.
At last, my scoop could bring the soil inside.
04On July 28, my robot arm collected the first soil samples for the instruments. The recovered sampler turned distant photographs into hands-on chemistry. The locked seismometer was still a limitation: a silent instrument did not mean a quake-free planet.

The big idea

Cameras can be engineering tools as well as science tools. Testing a command on a duplicate helps reduce risk when the real machine is far away.

Think about it

What should engineers check before moving a jammed mechanism again?

Fact file

First surface photograph
PIA00381 / 20 July 1976
Camera 2; the NASA caption identifies part of footpad 2 at the right.
Source ↗
Sampler recovery
Stuck locking pin / about five days
NSSDCA summary. Exact pin number, bracket temperature and midday maneuver from the draft are not asserted.
Source ↗
First soil sampling
28 July 1976
Samples delivered to the instruments after the sampler was recovered.
Source ↗

In this chapter: Two facsimile cameras, calibration targets, seismometer and surface sampler

Sources: Main record · Viking 1 Lander · NSSDCA Master Catalog · PIA00381 · NASA Image and Video Library · PIA00563 · NASA Image and Video Library · Viking 1 · NASA Science

Machine illustration: AI-made. Photos: NASA Image and Video Library, credited on each picture.

Chapter 2 of 5

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