Quick LRV question

[BertieSlack]

IIRC, each wheel was driven by its own electric motor. Did the bearings require any lubrication? Or were they dry-lubricated? Does direct drive even require bearings? A hoaxnut is claiming he can see leaking axle grease in an EVA photo. Help me address his (and my) ignorance. Thanks in advance.

[Obviousman]

It seems each drive was sealed. See attachment.

[Obviousman]

Also this.

[BertieSlack]

It seems each drive was sealed. See attachment.

Thanks for the quick response. I'll get back to hoaxer.

[onebigmonkey]

I'm curious as to what is being seen as axle grease!

[Obviousman]

Ditto.

[BertieSlack]

I'm curious as to what is being seen as axle grease!

The hoaxer didn't give the reference number of the EVA photo. I'll try to find it.

[BertieSlack]

I'm curious as to what is being seen as axle grease!

The hoaxer didn't give the reference number of the EVA photo. I'll try to find it.

Found it: https://www.hq.nasa.gov/alsj/a17/AS17-146-22296HR.jpg

[Obviousman]

He's not referring to the dust, is he? On the wheel, near the axle, etc?

[BertieSlack]

He's not referring to the dust, is he? On the wheel, near the axle, etc?

Yep - he's referring to the dust. Would electrostatics be part of the reason it sticks like that?

[Bryanpoprobson]

Yep - he's referring to the dust. Would electrostatics be part of the reason it sticks like that?

Would have been my first thought, the astronauts claimed it clung to everything.

[bknight]

He's not referring to the dust, is he? On the wheel, near the axle, etc?

Yep - he's referring to the dust. Would electrostatics be part of the reason it sticks like that?

I'm not sure about electrostatics, but from the post EVA images of the astronauts dust was covering them, A17 complained of regolith getting underneath their fingernails after the EVA's.

[Zakalwe]

The dust is, according to Gene Cernan, one of the biggest challenges to Lunar exploration. The Sun's rays charge it (via UV and soft X-ray photons) it so it not only clings electrostatically, but it also lifts itself up and travels along magnetic fieldlines.

https://en.wikipedia.org/wiki/Lunar_soil#Moon_dust_fountains_and_electrostatic_levitation

www.lpi.usra.edu/meetings/lsc1972/pdf/1011.pdf

http://onlinelibrary.wiley.com/doi/10.1029/2005RG000184/full  (Section 3.1)

As for the hoaxie's belief that the bearing is leaking, he is using his limited knowledge of the world and applying it to a very strange environment. If only he'd dig a bit deeper then he'd open up a world of interesting articles about the strangeness of Lunar regolith. I guess that if he did that though then he wouldn't be a conspiratard.