Bob Moler's Ephemeris Blog

Ephemeris for Tuesday, September 10th.  The sun will rise at 7:15.  It’ll be up for 12 hours and 46 minutes, setting at 8:02.   The moon, 2 days before first quarter, will set at 10:49 this evening.

Tonight the moon will reveal the entire Sea of Tranquility or Mare Tranquilitatis on the moon’s equator near the terminator or sunrise line that makes the moon look like a crescent.  The sun is rising right now (morning of the 10th) on the Apollo 11 landing site dubbed Tranquility Base by Neil Armstrong right after landing on July 21st 1969.   When showing the moon we are often asked, partly in jest we hope, if they could see the flag left by Armstrong and Aldrin.  The answer is no.  From the earth, we can barely see anything less than two miles in diameter.  It took the Lunar Reconnaissance Orbiter to dip down real low, less than 15 miles altitude, to capture an image of the landing site and what the astronauts left behind.  Incidentally the flag was knocked down by the blast of the ascent engine on their lunar module when they took off from the moon.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

The Moon tonight, 9 p.m. September 10, 2013, with the Apollo 11 landing site marked. Created with Virtual Moon Atlas.

Apollo 11 Base from the Lunar Reconnaissance Orbiter. Credit:  NASA.

LM is the descent stage of the Lunar Module that served as a launch platform for the ascent stage.

LRRR is the bank of retro reflectors that are still used to reflect earth based lasers to get an extremely accurate range to the Moon.

PSEP is a solar powered instrument package to monitor moonquakes and other information back to Earth after the astronauts had left the Moon.

The flag is not visible about a third of the way between the LM and the camera.

The dark lines are the tracks of the astronauts as they went about their exploration and equipment set up.