Are Neil Armstrong's footprints still perfectly preserved on the moon?

[Spoke]

There being no lunar atmosphere to blow the dust around, are the footprints going to be there indefinitely?

Would gravity, or maybe the motion of the moon, cause the dust to settle over time?

[Swede_Hollow]

Yes. The prints are likely to last for millions of years. The likely source of destruction of the prints would be a meteor impact (whether direct or nearby impact).

[Loopus]

What about moonquakes?

[JS_Princeton]

The moon has no seismic activity.

[Opengrave]

*Originally posted by Loopus *
What about **moonquakes? **

Band name!

[KneadToKnow]

Y’all have it all wrong: they were obliterated on July 2, 1996.

[DarrenS]

How about micrometeorites? According to this NASA page, those are what caused the lunar surface to be the way it is anyway. Won’t future impacts of micrometeorites erase the footprints?

[bernse]

I’ve been wondering this for a while:

Wouldn’t the ascent engine of the lander have obliterated them when it took off from the surface?

[JS_Princeton]

Micrometeorites deposit about 3mm of dust per million years.

[K364]

After the first step, did Armstrong and Aldrin make an effort to preserve the first footprint?

As for Bernse’s question: the ascent stage of the LM takes off using the descent stage as a platform, maybe that provided some protection? In a vacuum, the exhaust gases meet no atmospheric obstruction, but on the other had, there is no “swirling” effects in the air (because there is no air) I’m not sure if that would help or hurt in this situation.

[Mr.Miskatonic]

*Originally posted by JS Princeton *
**Micrometeorites deposit about 3mm of dust per million years. **

<Looks at watch, stares at footprint on ground, taps foot>

“C’mon!!!”

[kanicbird]

Wouldn’t the ascent engine of the lander have obliterated them when it took off from the surface?

Possibly the ones near the lem but they sometimes traveled quite far from the lem (later missions traveled the furthest.)

[TheeGrumpy]

Wouldn’t the ascent engine of the lander have obliterated them when it took off from the surface?

posted by **k2dave **
Possibly the ones near the lem but they sometimes traveled quite far from the lem (later missions traveled the furthest.)

Armstrong & Aldrin didn’t travel very far from the LM in under two hours of moonwalking. Armstrong did go as far as one crater 60 meters away. Are his tracks out to that point still there to this day?

I say, let’s go there and find out!

[Squink]

millions of years

I’d like to see a reliable and current cite for that number.
A search on “lunar regolith” gardening reveals a variety of processes, including meteroid impact, slumping, suspension of charged powders etc. that could affect the lifetime of Armstrong’s footprints. I’ve seen lifetime estimates as low as a few hundred years, but can’t find them online. Anyone ?

[bernse]

*Originally posted by k2dave *
**

Possibly the ones near the lem but they sometimes traveled quite far from the lem (later missions traveled the furthest.) **

OK, so could one then say the most important one, the first is almost certainly gone?

[Northern_Piper]

Originally posted by Squink *
** I’d like to see a reliable and current cite for that number.*

Well, this site says:

The Moon has preserved featured formed almost 4 billion year ago, and if men had landed on the Moon a billion years ago, it would have looked very much as it does now. The surface of the Moon now changes so slowly that the footprints left by the Apollo astronauts will remain clear and sharp for millions of years.

[Futile_Gesture]

New Scientist: http://www.newscientist.com/lastword/answers/677universe.jsp?tp=universe1

It figures a complete dust turnover in about 10,000 years.

[Northern_Piper]

*Originally posted by JS Princeton *
The moon has no seismic activity.

The Apollo program tested the moon for seismic activity and found that it has some weak “moonquakes.” Some come from the impact of meteroites, but others seem to come from tidal stresses. At any rate, they seem to have found enough measurable activity to make conclusions about the internal structure of the moon’s core.

From What’s New on the Moon?

About 3,000 moonquakes are detected each year. All of them are very weak by terrestrial standards. The average moonquake releases about as much energy as a firecracker, and the whole Moon releases less than one-ten-billionth of the earthquake energy of the Earth. The moonquakes occur about 600 to 800 kilometers (370-500 miles) deep inside the Moon, much deeper than almost all the quakes on our own planet. Certain kinds of moonquakes occur at about the same time every month, suggesting that they are triggered by repeated tidal strains as the Moon moves in its orbits around the Earth.

See also: Apollo 12 Passive Seismic Experiment

[GIGObuster]

*Originally posted by TheeGrumpy *
**

Armstrong & Aldrin didn’t travel very far from the LM in under two hours of moonwalking. Armstrong did go as far as one crater 60 meters away. Are his tracks out to that point still there to this day?

I say, let’s go there and find out! **

The fellows at LunaCorp are getting ready to get a new look:
http://www.lunacorp.com/lcrover.htm

The Route
Launching in at the turn of the Millennium, the rovers will land east of the Apollo 11 landing site. After system checkout, the rovers will proceed to the Apollo 11 site, where they will Buzz Aldrin’s historic footprints from a respectful distance. The rovers WILL NOT disturb any part of the site, instead bringing back video footage from vantage points around the actual site. From there, the rovers will investigate the Surveyor 5 and Ranger 8 sites, including examining what 35 years in a vacuum can do to man-made objects. From there, the rovers will head north, nearly 1000 km, to the Apollo 17 landing site in the Taurus Littrow valley, to see the site of the last human voyage to the Moon in 1972. Finally, the rovers will head north again to find the final resting place of the Soviet Lunokhod II rover, which explored the Moon for four months in 1973. In total, the mission will last over two years.

[JS_Princeton]

Here’s the source for accumulation due to micrometeorites. Sorry, I couldn’t find a public copy available on the web…

Title:
Time Scale for the Micrometeorite and Solar Flare Maturation of Lunar Soils
Authors:
Poupeau, G.; Johnson, J.
Journal:
Abstracts of the Lunar and Planetary Science Conference, volume 7, page 709, (1976)
Publication Date:
00/1976
Category:
Lunar Science
Origin:
METBASE
Bibliographic Code:
1976LPI…7…709P