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Ephemeris: 09/13/2024 – International Observe the Moon Night tomorrow
This is Ephemeris for Friday, September 13th. Today the Sun will be up for 12 hours and 36 minutes, setting at 7:56, and it will rise tomorrow at 7:21. The Moon, 2 days past first quarter, will set at 2:25 tomorrow morning.
Tomorrow night, if it’s clear, will be the last star party of the year at the Sleeping Bear Dunes National Lakeshore starting at 9 PM if it is clear. It coincides with the International Observe the Moon Night, which is held annually in September or October near the first quarter moon, give or take a few days. Hosting the event will be the Park Rangers and the Grand Traverse Astronomical Society. Also featured will be the planet Saturn which is exhibiting some very thin rings this year. The 2020s appears to be the decade of the Moon with the United States and its European and Canadian partners, China, Russia, and even India interested in landing instruments and people on the Moon. So far this decade only China and India have had completely successful landings of spacecraft on the Moon.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Ephemeris: 09/12/2024 – Does the Moon have a square crater?
This is Ephemeris for Thursday, September 12th. Today the Sun will be up for 12 hours and 39 minutes, setting at 7:58, and it will rise tomorrow at 7:19. The Moon, 1 day past first quarter, will set at 1:11 tomorrow morning.
I built my first telescope in the mid 1950s from the kit. It had a 5-inch diameter mirror. Of course one of the first things I looked at was the Moon. And while familiarizing myself with the Moon’s features I noticed that around first quarter moon there was a funny little crater near the Moon’s North Pole that looked square. All the other craters were round. This one being near the North Pole was foreshortened a bit, so it’ll look rectangular. It sure had walls that looked like they were straight rather than curved. The crater’s name is Barrow. And the description I found of it said it had an interesting shape, though they didn’t mention it was square. Looking closely at it, it is squarish but in small telescopes it definitely looks like it’s a square crater. The best time to try to spot it is around first quarter moon or up to a couple of days later.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
The base imagery used for the Virtual Moon Atlas, I believe, came from the Clementine spacecraft, a joint project of NASA and the Department of Defense, which orbited the Moon for 71 days in the mid 90s and then was sent out to an asteroid. However, on the way to the asteroid a problem occurred and Clementine was “lost and gone forever”.
Ephemeris: 08/13/2024 – Antares and the Moon
This is Ephemeris for Tuesday, August 13th. Today the Sun will be up for 14 hours and 7 minutes, setting at 8:50, and it will rise tomorrow at 6:44. The Moon, 1 day past first quarter, will set at 12:41 tomorrow morning.
The Moon tonight will have a companion. Just to the left of it will be a star. That star may not look very bright because it is overpowered by moonlight, but it is one of the brightest stars of the sky. It is Antares in Scorpius the scorpion, a red giant star. Every month for the last several years and for the next several years the moon will pass in front of that star. Unfortunately due to the timing and to the path of the Moon it doesn’t happen for any particular spot on the Earth very often. Tonight, as the Moon sets it will be approaching Antares but will appear about to pass below it at the time it sets. We will not be able to see the Moon actually cover or occult Antares from Northern Michigan until May 2028, nearly four years from now.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT–4 hours). Times will be different for other locations.
Addendum
Ephemeris: 07/18/2024 The brightest spot on the Moon
This is Ephemeris for Thursday, July 18th. Today the Sun will be up for 15 hours and 7 minutes, setting at 9:22, and it will rise tomorrow at 6:15. The Moon, 3 days before full, will set at 3:40 tomorrow morning.
The moon tonight is bright. The sunrise line or terminator on the moon is crossing the large gray plain called Oceanus Procellarum, the largest of the moon’s seas. These seas were figments of the first telescopic observer’s imagination. They are really huge impact basins into which interior lava flowed. On the left side of the Moon is a bright spot in the gray expanse of Oceanus Procellarum visible in binoculars. In a telescope it is a crater called Aristarchus. It is a fairly new crater in lunar terms, probably less than a billion years old. As a rule the brighter the crater the newer it is. Aristarchus is the brightest spot on the Moon. Over the years visual astronomers have seen hazes and bright spots from time to time in and near Aristarchus.
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
Ephemeris: 07/16/2024 – Find the rabbit in the Moon
This is Ephemeris for Tuesday, July 16th. Today the Sun will be up for 15 hours and 11 minutes, setting at 9:24, and it will rise tomorrow at 6:13. The Moon, 3 days past first quarter, will set at 2:10 tomorrow morning.
The Moon tonight is a gibbous phase which is between first quarter and full. The sunrise line we call the terminator is moving across the lunar sea Oceanus Procellarum, or Ocean of Storms. As I look at the Moon more and more, I’m beginning to appreciate what the Chinese saw in the pattern of the lunar seas, that of a rabbit. A very particular rabbit named Yutu, belonging to the moon goddess Ching’e. He’s curled up head down towards the right. His two rabbit ears, his head and part of his body is displayed in the five connected seas of Fecunditatis (Fruitfulness), Nectaris (Nectar), Tranquillitatis (Tranquility), Serenitatis (Serenity), and Imbrium (Showers). The rest of his body is slowly being revealed by the advancing terminator to the left. He is shown with a mortar, the sea Nubium (Clouds) and pestle pounding out medicine according to Chinese mythology.
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
The Chinese lunar landers have been named Chang’e, and the rovers named Yutu.
Ephemeris: 07/12/2024 – Star Party tomorrow night at Sleeping Bear Dunes National Lakeshore
This is Bob Moler with Ephemeris for Friday, July 12th. Today the Sun will be up for 15 hours and 17 minutes, setting at 9:27, and it will rise tomorrow at 6:10. The Moon, 1 day before first quarter, will set at 12:42 tomorrow morning.
Tomorrow night, Saturday, July 13th, the Sleeping Bear Dunes National Lakeshore will team up with the Grand Traverse Astronomical Society to host a star party at the Dune Climb from 9 to 11 PM or later. It won’t be a star party only, because the featured attraction will be the first quarter Moon. To my mind, this is the best time to view the Moon, showing its craters with deep shadows near the terminator or sunrise line which crosses the Moon slowly over the month. There are no planets out in the evening, but we do have some interesting stars to look at besides the Moon. And the bright International Space Station will be seen moving from west to northeast, passing through the bowl of the Big Dipper around 10:28 pm.
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
Translations of some lunar feature names according to Virtual Moon Atlas
Mare Crisium – Sea of Crises
Mare Fecunditatis – Sea of Fruitfulness
Mare Frigoris – Sea of Cold
Mare Imbrium – Sea of Showers
Mare Nectaris – Sea of Nectar
Mare Serenitatis – Sea of Serenity
Mare Tranquillitatis – Sea of Tranquility
Mare Vaporum – Sea of Vapors
Montes Alpes – Alps Mountains
Montes Apenninus – Apennines Mountains
Craters are named for persons, real or otherwise.
Ephemeris: 07/11/2024 – Low energy routes to get to the Moon
This is Ephemeris for Thursday, July 11th. Today the Sun will be up for 15 hours and 19 minutes, setting at 9:27, and it will rise tomorrow at 6:09. The Moon, 2 days before first quarter, will set at 12:26 tomorrow morning.
Back in the Apollo days when we sent people to the Moon, the trip out was only three days. The latest generation of unmanned probes to the Moon sent by the United States and other countries can take days, weeks, or even months to reach the Moon, so what’s going on? These are robot probes, needing little power. Humans however are high maintenance. Even when they’re doing nothing they are breathing, eating, and using resources. So when humans are aboard you have got to get there fast. Also, many of these probes are CubeSats, no bigger than a breadbox*. They must get into orbit of the Moon with very little thrust other than that of the rocket that launched them. They can go out as far as a million miles away before falling back to the Moon.
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.
* OK, I’m an old guy, the modern size comparison would be a microwave.
Addendum
Ephemeris: 07/09/2024 – The Moon Tonight – Mare Crisium
This is Ephemeris for Tuesday, July 9th. Today the Sun will be up for 15 hours and 22 minutes, setting at 9:29, and it will rise tomorrow at 6:07. The Moon, halfway from new to first quarter, will set at 11:53 this evening.
Tonight’s four-day old crescent Moon will be seen in the west at about 10:30 PM, though it’s visible much earlier than that. Binoculars will show a small gray round area near the right edge of the Moon which is seen in the full moon as the eye of the Man in the Moon. The feature is called Mare Crisium or the Sea of Crises. And is an Oval 385 by 354 miles in extent. However, it is elongated east to west rather than what it appears to be, north to south. That is due to foreshortening because it is near the limb of the Moon and thus curved away from us. So we are looking at it at an oblique angle. Mare Crisium is thought to be the result of an impact of an asteroid that occurred nearly 4 billion years ago during the Late Heavy Bombardment.
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
Ephemeris: 06/18/2024 – Are we in a space race with China?
This is Ephemeris for Tuesday, June 18th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:31, and it will rise tomorrow at 5:56. The Moon, 3 days before full, will set at 3:41 tomorrow morning.
Back in the late 1950s and early 1960s The United States and Russia were in a space race, attempting to outdo each other in space. The Russians had the lead to begin with. Their rockets were bigger because they were unable to miniaturize their atomic weapons. So they needed rockets large enough to launch them, and had rockets large enough, off the shelf so to speak, to be able to launch satellites and even humans into orbit. Sixty years later the old Soviet Union has disappeared and Russia is still using rocket technology that was developed in the 1960s. The Chinese however, were nowhere in the 1960s, and have now ascended to be our number one competitor in space. Considering their latest progress, China may beat us back to the Moon.
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
Ephemeris: 06/17/2024 – China’s mission to get samples from the far side of the Moon
This is Ephemeris for Monday, June 17th. Today the Sun will be up for 15 hours and 34 minutes, setting at 9:31, and it will rise tomorrow at 5:56. The Moon, 3 days past first quarter, will set at 3:16 tomorrow morning.
Earlier this month the People’s Republic of China’s Chang’e 6 spacecraft landed on the far side of the Moon to collect samples to return them to the Earth. They had put a satellite in orbit of the moon to act as a relay satellite so they can communicate with their Lander. The collection went according to plan and the spacecraft is now headed back to the Earth. It is my understanding that they landed in the crater called Apollo at the edge of the Aitken basin . Being the far side of the moon the Apollo crater is not named for the Greek god but for the American human Moon program of the 1960s and early 70s. The samples are expected to return to Earth on the 25th. These are the first samples from the far side of the Moon to be returned.
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
Bob Moler's Ephemeris Blog 