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28

Hubble can in fact observe the Moon, and has done so. Here's a picture of the Apollo 17 site (The upper right is from Apollo 17 mission itself). The x shows where the actual site is. You can also see more Hubble pictures of the Moon at this page.


18

There is a map of lunar pits, created by R. V. Wagner and M. S. Robinson of the School of Earth and Space Exploration, Arizona State University, in 2014. From Distribution, Age, and Formation Mechanisms of Lunar Pits (PDF) by mentioned authors: Map of the locations of all currently-known pits. Orange stars indicate mare or highland pits, and blue ...


14

See this paper from P. J. Stooke, Department of Geography and Centre for Planetary Science and Exploration, University of Western Ontario, London, Ontario, Canada about the Apollo 12 and 14 impact sides. Many details and images about impact sites in this page with additional data about Apollo 15 and 17. A NASA page with the Lunar coordinates of the impact ...


13

The deviations are real and directly related to the size of valleys on the Moon. The simple calculation you do here does only work for a point-like light source that projects the shape of the Moon onto Earth. In case of an eclipse, the light source has almost the same apparent size as the object. For this eclipse, the magnitude is given as 1.03. This is the ...


10

LRO was inserted into a polar frozen orbit for commissioning, which required no stationkeeping. This orbit was a stable 31.5 km x 199 km polar orbit with periapsis over the South Pole. By "frozen" they mean that the line of apsides and eccentricity remain fixed. It then moved into a 50km circular polar orbit (+/- 20 km) for its science mission. This ...


8

The explanation has to do with the operation of the radar transmitters and the round trip light travel time. It takes about 3 seconds for a radar pulse to travel from the Earth to the Moon and back. The planetary radar transmitters are high power; the Goldstone transmitter (at full strength) is 500 kW, the Arecibo transmitter is nearly 1000 kW. By ...


6

JPL HORIZONS features orbits interpolated from actual data rather than pure simulations. I suspect that what happened here is that there is no orbital data for the three sections of data that don't exhibit the oscillation. We know for a fact that there is no raw data for one of those sections because it is in the future. I spoke to a controls expert and he ...


6

I'll add this to the other answers, which do a very good job of explaining why this very irregular shape is not inconsistent with the Moon's original much "rounder" shape. This could be done with some geometry and math, but I was lazy and did a rendering in Blender. I made a spheroid and added some bumps, then added a Sun lamp above and screen far below. I ...


5

I believe COS (the sensitive UV instrument) could be damaged if it were pointed at the illuminated moon. (I wasn't able to find any documents online that confirm this though) The instruments don't point in the same direction. So it's possible to orient the telescope so that one is not pointed at the moon while others are. Lunar observations are difficult ...


4

I sent an email which started a chain (Jennifer Brill, John Keller, Emmanuel Dziwornooh). At some point during that, https://lrostk.gsfc.nasa.gov/ came back up. John Keller acknowledged that the site has intermittent problems and asked the sysadmins to ensure it stays up more reliably.


4

The outline of the lunar umbra on Earth (shadow of totality) will be defined by those rays of light emanating from the very edge of the solar disk as seen from Earth which just miss the surface features at the lunar terminator (line between day and night on the Moon's surface). Because the Moon is some 500 times smaller than the Sun (by diameter), those rays ...


4

tl;dr Those numbers are meters per pixel. But you have to be careful because they are scans along the spacecraft orbit with the moon rotating underneath, so x and y are skewed. This answer will get you started. The LRO is an amazing spacecraft with a wide variety of instruments to map the moon's surface by a number of characteristics as well as ...


4

These are standard terms used by the Planetary Database System. MSSS provides some explanations of these terms. Product ID- Each product (image) has a unique id, if you know the exact image, put this one in. Coordinate Range- Range to the coordinates from the spacecraft. Incidence Angle- This is the angle that the sun is to the surface. A low angle means ...


3

Since the deep space network can perform ranging on spacecraft much farther away (tens of thousands of times farther than the moon) by itself, why was it necessary to use a non-colocated, non-DSN dish to receive signals in this case? The ranging you're referring to is cooperative radio ranging: The DSN sends a signal to the spacecraft, the spacecraft ...


3

I know nothing of the activity you're asking about, but I do know something about radar. All the radar systems I've worked with used a single antenna to both transmit and receive. The power of the transmitter is very large compared to the return echo that needs to be received, and the very sensitive receiver needs to be disconnected from the antenna when ...


2

tl;dr: The 125 mm proven receiving telescope design used on the receiving telescope of the MLA laser ranger used on MESSENGER was adapted and enlarged to 150 mm for the LOLA of LRO. I am guessing that this was felt far more prudent than a new design using reflective optics based on exotic materials like silicon carbide. This page on LOLA links to Optical ...


2

I tried to do the same using python: import numpy as np a = 1737400 x_g = -411141.107140 y_g = -411325.894877 x = x_g/np.sqrt( 1 + np.square(x_g/a) + np.square(y_g/a) ) y = y_g/np.sqrt( 1 + np.square(x_g/a) + np.square(y_g/a) ) z = a/np.sqrt( 1 + np.square(x_g/a) + np.square(y_g/a) ) print('(x, y, z) = ', (x, y, z)) x_s = 2*a*y/(a + z) y_s = 2*a*x/(...


1

I had to set up a whole page to experiment with Horizons, and after weeks of testing I ended with this url, which you can see here exploded for better readability: https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1 COMMAND='-85' <---- Target: LRO orbiter CENTER='coord@301' <---- Observer: Specify coordinates of point on surface with ...


1

The pixel size of the HST's Wide Field Camera 3 or WFC-3 is 164/2048 = 0.08 arcsec. The night side of the Moon is illuminated by Earthshine and the brightness depends on the phase angle of the moon (and the weather on Earth (clouds, wind-induced waves on the ocean) and the time (ocean versus land) but we can find some averages. Let's use +15 magnitude per ...


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