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Posts Tagged ‘Far side’

Ephemeris: 04/11/2024 – What is the far side of the Moon good for?

April 11, 2024 Comments off

This is Ephemeris for Thursday, April 11th. Today the Sun will be up for 13 hours and 19 minutes, setting at 8:23, and it will rise tomorrow at 7:02. The Moon, 3 days past new, will set at 12:40 tomorrow morning.

The Last Monday when we were having an eclipse of the Sun, the far side of the Moon was fully illuminated. So it can’t possibly be the dark side of the Moon, not permanently. The dark side of the Moon is the night side and Monday that was the side facing the Earth. But what’s the far side of the Moon good for? The Chinese seem to be very interested in it. They have a lander and a rover on the far side, and they’re going to go back and grab a sample from the far side and bring it back to the Earth. The far side of the Moon is one place in the whole solar system in which the cacophony of radio signals from the Earth cannot be heard so it’s a great place to set up a radio telescope. The craters on the far side of the moon might be used to place a dish antenna.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT–4 hours). They may be different for your location.

Addendum

Near Side and Far Side of the Moon Compared
The near side and the far side of the Moon compared. Notice how different they are with the near side dominated by the dark lava seas and the far side by the less dark highlands. The one sea on the far side is at 10 o’clock is the Sea of Moscow, and the other dark spot to the lower lower left about 8 o’clock is the crater Tsiolkovsky named after famous Russian scientist Konstantin Tsiolkovsky (1857-1935)a pioneer in aeronautic, and rocket theory. The Soviets were first to send a probe (Luna 3) around the far side of the Moon in 1959, and got to name the major features they photographed.
Lunar Crater Radio Telescope
A concept for a lunar crater radio telescope . The telescope is in the style of Arecibo, the now collapsed radio telescope in Puerto Rico . Aiming would be accomplished by shifting the suspended receiver. Credit: NASA, Saptarshi Bandyopadhyay.
Categories: The Moon Tags: ,

Ephemeris: 01/23/2024- The “dark” side of the Moon is its brightest side

January 23, 2024 Comments off

This is Ephemeris for Tuesday, January 23rd. Today the Sun will be up for 9 hours and 27 minutes, setting at 5:38, and it will rise tomorrow at 8:10. The Moon, 2 days before full, will set at 8 o’clock tomorrow morning.

In a couple of days the far side of the Moon will become the dark side for real. It’ll be night when the near side of the moon becomes fully illuminated, the far side will be a night. The far side of the moon actually gets more sunlight than the near side of the moon because it does not suffer solar eclipses. The lunar solar eclipse occurs when we see a lunar eclipse. The Sun is blocked from shining on the Moon. The totality of a lunar solar eclipse lasts much longer than a few minutes that we get when the Moon totally blocks the Sun, the length of totality for the Moon’s solar eclipse can last several hours. The far side of the moon does not see eclipses, and when fully illuminated at what we call new moon it is a quarter of a million miles closer to the Sun than Earth.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

The near side and the far side of the Moon compared
The near side and the far side of the Moon compared. On the far side the only really dark areas are the Moscow Sea at the 10 o’clock position and the crater Tsiolkovsky at the 8 o’clock position. The large semi dark area at the 5 o’clock position is the Aitken basin which would probably be a lot darker if the impact that created it had occurred on the near side of the Moon. Click or tap on the image to enlarge it. Credit NASA, Clementine spacecraft.
Categories: Ephemeris Program, The Moon Tags: , ,

03/11/2019 – Ephemeris – The Moon: Dark side, far side, which is it?

March 11, 2019 Comments off

Ephemeris for Monday, March 11th. Today the Sun will be up for 11 hours and 40 minutes, setting at 7:43, and it will rise tomorrow at 8:01. The Moon, 3 days before first quarter, will set at 12:54 tomorrow morning.

Tonight the Moon is at its crescent phase, meaning it is slightly closer to the Sun than the Earth is. Most of the Moon we see is in night. Some earth shine may be seen on its night side due to the big nearly full Earth shining on it. I get ticked sometimes when someone who knows better, especially in the media, mentions the dark side of the Moon when they should use the term far side, the part of the Moon that permanently faces away from the Earth. When the Chinese Chang’e 4 spacecraft landed on the far side of the Moon recently many headlines proclaimed that it landed on the dark side of the Moon. The Moon has a night side, as does the Earth, but that changes as the Moon rotates in the sunlight.  And the Moon does rotate.  It happens to be in sync with its revolution about the Earth.

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

Addendum

Crescent Moon

The crescent Moon tonight at 9 p.m. EDT, March 11, 2019. Created using Stellarium.

Moon ball

Demonstration of the Moon’s crescent phase with the Styrofoam moon ball we use for Project Astro held up to a light off frame to the right. The night side of the ball is illuminated a bit by the translucency of the ball, and the reflection off my hand. Note the roughness of the ball is visible only at the terminator.

The crescent Moon and its relation the Earth

The Earth and Moon if seen as a crescent, near side, far side, sunlit side and earth shine. Credit: me.

Categories: Concepts, Ephemeris Program, Phases, The Moon Tags: , , ,