"It's just gone."

  

Edgar Mitchell moves across the lunar surface as he looks over a traverse 

map while exploring the Fra Mauro region. Credit: NASA/Alan Shepard

I have been studying the technical details of lunar exploration for a while now.  I think the archives have important information that will help Artemis explorers and mission planners.

While reading through the "Apollo 14 Technical Crew Debriefing" from 1971, I found some interesting comments from lunar module pilot Ed Mitchell about visibility on the lunar surface.

"In looking out the window from the LM [Lunar Module], I had a very definite impression of the relief. I think we stated several times that the relief was greater than we expected. However, I observed that when we got on the lunar surface, subsequent to that, that your observation of the relief changes with Sun angle.

The Sun wipes out, or seems to smooth out, a lot of relief that you see at certain Sun angles and that you just don't see at other Sun angles. Or maybe the visor distorts it in some way. But sometimes you see a very good sized, crater, a depression ahead of you. You look at it at a different angle and it's just gone.

When you turn your head a different way, you don't see it. So, perhaps there's a bit of distortion in the visors. You're never quite sure whether it's visor distortion or whether it's Sun angle or what it is that causes you to see these things or not to see them at a particular point in time."

Source: Apollo 14 Technical Crew Debriefing, February 17, 1971, https://www.hq.nasa.gov/alsj/a14/a14-techdebrief.pdf

 

This aligns with similar startling observations from Apollo 16 commander John Young posted here: https://outwardspace.blogspot.com/2021/09/apollo-16-invisible-obstacles.html

Visibility issues related to a combination of sun angle and/or visor distortion may pose a hazard to future lunar explorers.  

Depending on the landing site, a mission lasting one lunar day (about 30 Earth days) will expose Artemis astronauts to every possible sun angle, including possible weeks of darkness.

Your Mission: Find a Lunar Landing Site

The Artemis mission planners need your help. When we go back to the moon in the next few years, where should we land?

Your job is to review five different places and decide where we should build an outpost.

These places are:

1. Highlands
2. South Pole
3. Aristarchus
4. Tranquility
5. Far Eastern

You rate each place based on these factors:

1. Water and Resources
Can be used for water and fuel. May occur as ice on the Moon, delivered by comets and maintained in Permanently Shadowed Regions (PSRs) near the poles.

Batteries are heavy payload to send to the Moon. Solar power will be a primary source. Fuel could come from the break down of water ice into oxygen and hydrogen.

Aluminum, titanium, iron, loose lunar regolith to make “lunar bricks” all offer building resources.

2. Terrain Smoothness (Topography)
Flat terrain is best, not near steep cliffs, mountainous regions or areas with lots of boulders.

3. Temperature and 4. Radiation
Natural habitats or resources, such as lava tubes (ancient caves created where lava once flowed) or soil to cover a base or make lunar bricks, offer protection from radiation and extreme temperatures. If not available, a base will need to be built.

5. Science
What are the interesting science questions to be addressed?

6. Special Considerations
Needs a clear line of sight to Earth, or a more costly satellite system will be needed.

 

Use a grid and fill in the squares with "Go", "No Go", or "Need Info"

Full mission info is here:

[1] Mission Overview; https://www.lpi.usra.edu/education/explore/LRO/activities/mission_moon/mission_team_overview.pdf

[2] Site Information; https://www.lpi.usra.edu/education/explore/LRO/activities/mission_moon/site_info.pdf

Water on the Moon?

Scientists have discovered that water is being released from the Moon during meteor showers. 

When a speck of comet debris strikes the Moon it vaporizes on impact, creating a shock wave in the lunar soil. For a sufficiently large impactor, this shock wave can breach the soil's dry upper layer and release water molecules from a hydrated layer below.

Source: NASA