Recent comments in /f/askscience

austinmiles t1_jbdapl4 wrote

Reply to comment by Aubin_kun in How much influence does a natural satellite (like the Moon) have on the formation of continents ? by Aubin_kun

There are also moons that have such a strong reaction to their planet that they have geological activity. Enceladus and Europa both have liquid oceans because of the heat generated by tidal flexing.

If your moon was large enough it could cause enough upheaval that over a long period of time it could change the landscape either through much more active tectonics or from things like volcanos which could look very different.

2

ChrisGnam t1_jbd8sc9 wrote

Reply to comment by Astrokiwi in When humans next land on the moon, will our telescopes from Earth's surface be able to photograph the rocket on the moon's surface? by Nswl

> ...you get much better resolution by sending a small telescope to orbit the Moon ...

Just to comment on this part, we already have such a probe! We at NASA Goddard operate tbe Lunar Reconnaissance Orbiter (LRO) which has two a Narrow Angle Camera's (LROC NAC-L and NAC-R), each have a focal length of ~700mm and so are effectively mini telescopes.

Infact, with these camera's we've been able to photograph the old Apollo landing sites

If anyone is interested in diving further, all the imagery taken by the LRO is available to the public and can be explored using the LROC QuickMaps tool. If you zoom in you'll see the actual mosaic of NAC images. You may be wondering why each segment of the image looks really long, and this is because NAC is a push-broom sensor rather than a framing one. A framing sensor (like in most camera's today) is a rectangular grid of pixels where each pixel on the sensor is sampled once and corresponds to one pixel in the final image. A push-broom sensor is a single line of pixels, which each pixel represents a column of the final image. It is sampled at a regular interval, and each time it's sampled, that forms a new row of the image. So as you fly over a surface, you construct the image one row at a time. It maps the surface kinda like you're pushing a broom over the surface, hence the name.

9