Archive
09/17/2018 – Ephemeris – The Moon Tonight and the Jade Rabbit
Ephemeris for Monday, September 17th. The Sun will rise at 7:24. It’ll be up for 12 hours and 25 minutes, setting at 7:49. The Moon, 1 day past first quarter, will set at 1:03 tomorrow morning.
Now is a good time to point that small telescope or binoculars toward the Moon. The gray seas on the right side of the moon depict the neck, head and ears of the Jade Rabbit. It’s curled up body is on the night side of the Moon to the left. The rabbit is upside down as we see him with the naked eye or binoculars. The Sea of Serenity is the upper part of his body, the head is the Sea of Tranquility. A bay south of Tranquility and the Sea of Nectar is one ear and the Sea of Fertility is the other ear. The Jade Rabbit is related to the Chinese Mid-Autumn Festival which occurs at our Harvest Moon. It’s on September 24th this year. Another amateur astronomer and myself brought telescopes to the local festival last year to view the Jade Rabbit on the Moon.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
02/20/2018 – Ephemeris – Tonight’s the night to spot a chain of three of my favorite craters
Ephemeris for Tuesday, February 20th. The Sun will rise at 7:35. It’ll be up for 10 hours and 43 minutes, setting at 6:18. The Moon, 3 days before first quarter, will set at 11:29 this evening.
I was a day off in my Moon calculations yesterday. The three of my favorite craters, just south of the partially illuminated Sea of Tranquility will be visible tonight. From north to south or top to bottom, near the terminator or sunrise line is Theophilus, which slightly overlaps the crater wall of Cyrillus, then a bit farther south another older crater Catharina. These craters were named by a Jesuit astronomer Giovanni Battista Riccioli (Ri’cholli). He even named a crater Copernicus, even though he followed the Church teachings of the time he didn’t believe in the Copernican Sun centered system, but the system put forth by Danish astronomer Tycho Brahe where the Moon and Sun circled the Earth, but the other planets circled the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The crescent Moon on the evening of February 20th, 2018. showing the craters discussed in the test. Created using Virtual Moon Atlas and rotated to approximate its orientation in the sky after sunset.
Repeating from yesterday: For anyone east of here who can see the Moon at 19:00 UT, on the 20th should see Theophilus shadow filled with the crater rim and the central peak poking into sunlight. It should be visible from Europe and the Mid East. Let me know with a comment if I guessed right.
02/19/2018 – Ephemeris – A trio of craters emerge into sunlight on the moon tomorrow night
Whoops, I set my Virtual Moon Atlas app to the 20th instead of the 19th. I’m fixing the transcript for the blog readers, but the original program will go out as is. Tomorrow’s program will be substantially the same.
Ephemeris for President’s Day, Monday, February 19th. The Sun will rise at 7:36. It’ll be up for 10 hours and 40 minutes, setting at 6:16. The Moon, half way from new to first quarter, will set at 10:23 this evening.
The crescent Moon tomorrow will be revealing a trio of my favorite craters, just south of the partially illuminated Sea of Tranquility. From north to south or top to bottom, near the terminator or sunrise line is Theophilus, which slightly overlaps the crater wall of Cyrillus, than a bit farther south another older crater Catharina. These craters were named by a Jesuit astronomer Giovanni Battista Riccioli in his book New Almagest in 1651. Most of his crater names have stuck. He didn’t believe in the Copernican Sun centered system or the strict Earth centered system of Ptolemy, but the system put forth by Danish astronomer Tycho Brahe where the Moon and Sun circled the Earth, but the other planets circled the Sun.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The crescent Moon on the evening of February 20th, 2018. showing the craters discussed in the test. Created using Virtual Moon Atlas and rotated to approximate its orientation in the sky after sunset.
For anyone east of here who can see the Moon at 19:00 UT, on the 20th should see Theophilus shadow filled with the crater rim and the central peak poking into sunlight.
01/23/2018 – Ephemeris – The Moon tonight: the Sea of Tranquility and a crater named for Julius Caesar
Ephemeris for Tuesday, January 23rd. The Sun will rise at 8:10. It’ll be up for 9 hours and 28 minutes, setting at 5:38. The Moon, 1 day before first quarter, will set at 12:30 tomorrow morning.
Let’s take a look at the Moon tonight with binoculars or a small telescope. The crescent Moon tonight has completely revealed the Sea of Tranquility, or Mare Tranquillitatis. Right on the western edge, east to us, of the sea is a ruined crater called Julius Caesar. It seems to have formed by a small asteroid collision in the first half billion years of the Moon’s existance. It’s shape was distorted by the impact that created the Sea of Tranquility. The Moon’s so-called seas are all pretty much impact craters, just really big ones. North of Tranquility is the Sea of Serenity which will be completely in sunlight tomorrow night. By the way, the Grand Traverse Astronomical Society telescope clinic that was scheduled for January has been moved to February 2nd.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The fat crescent Moon at 8 p.m. January 23, 2018. Created using Virtual Moon Atlas.
The crater Julius Caesar from photographs supplied with Virtual Moon Atlas.
09/25/2017 – Ephemeris – Lets look at the Moon tonight
Ephemeris for Monday, September 25th. The Sun will rise at 7:33 a.m. It’ll be up for 12 hours exactly, setting at 7:33 p.m. The Moon, 2 days before first quarter, will set at 10:52 this evening.
Let’s take a look at the crescent Moon tonight. It will be fairly low in the southwestern sky this evening. Four of the gray lava plains called seas are now visible in binoculars or small telescopes. Nearest the right limb of the Moon is the Sea of Crises, next nearest if the Sea of Fertility. A small sea next to that is the Sea of Nectar. Above that, mostly exposed to sunlight is the Sea of Tranquility. The Sun is just rising at Tranquility Base, where Apollo 11 landed, where the Lunar Module’s descent stage still lies, forlorn and empty. Below that is the beautiful crater Theophilus with its central peak. It is 61 miles (101 km) in diameter, and its crater walls rise over 13,000 feet (4,400 meters) above the crater floor.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The annotated crescent moon tonight, September 25, 2017. Created using Virtual Moon Atlas. Click on the image to enlarge.
The Apollo 11 landing site in one photograph by the Lunar Reconnaissance Orbiter. There are many with varying Sun angles in the Internet. Search for: Apollo 11 LRO images. Credit NASA.
10/06/2016 Ephemeris – Viewing the Moon tonight
Ephemeris for Thursday, October 6th. The Sun will rise at 7:47. It’ll be up for 11 hours and 25 minutes, setting at 7:13. The Moon, 3 days before first quarter, will set at 10:44 this evening.
Tonight the waxing crescent Moon will appear between Saturn on the right and Mars on the left. In a small telescope the Sea of Tranquility is now mostly in daylight. The Sun will rise on the Apollo 11 landing site about one this afternoon. The landing site cannot be seen from the Earth, it’s artifacts are too small. The Lunar Reconnaissance Orbiter has to get down to about 15 miles altitude to photograph them. The craters of Theophilus, Cyrillus and Catharina are seen to the south of Tranquility. Just south of them there looks like a wrinkle in the Moon surface. It’s the Altai Scarp, which is named for the Altai mountains of central Asia. The three craters border the small Sea of Nectar. The lunar seas are basins of solidified lava.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Moon Chart for tonight (October 6, 2016) at 9 p.m. showing the areas discussed above. Created using Virtual Moon Atlas.’
The Apollo 11 landing site in one photograph by the Lunar Reconnaissance Orbiter. There are many with varying Sun angles in the Internet. Search for: Apollo 11 LRO images. Credit NASA.
05/12/2016 – Ephemeris – The Moon tonight
Ephemeris for Thursday, May 12th. Today the Sun will be up for 14 hours and 44 minutes, setting at 9:01. The Moon, 1 day before first quarter, will set at 2:26 tomorrow morning. Tomorrow the Sun will rise at 6:16.
The moon tonight is a fat crescent. In binoculars the small Sea of Crises is prominently located as a gray patch at the edge of the moon. The Sea of Fertility is below it, while the sea of Tranquility is between them and near the terminator, the sunrise line on the moon. In telescopes there are three craters south of Tranquility, most prominent of which is Theophilus. With its prominent central peak. Farther to the north of Crises and near the partially exposed Sea of Serenity is the crater Posidonius, larger than Theophilus, but has a double crater wall on one side. Larger telescopes can see cracks in its floor . It has no central peak, and shows its age of maybe three and a half billion years.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon at 10 p.m. May 12, 2016. Created using Virtual Moon Atlas.
03/06/2014 – Ephemeris – Observing the Moon tonight!
Ephemeris for Thursday, March 6th. The sun will rise at 7:11. It’ll be up for 11 hours and 25 minutes, setting at 6:36. The moon, 2 days before first quarter, will set at 12:56 tomorrow morning.
The Moon’s appearance has changed since I last talked about it on Tuesday. The Crescent is wider. The terminator, the sunrise line on the Moon that gives the Moon it’s now crescent phase has uncovered most of the Sea of Tranquility. In fact the sun will have risen at the Apollo 11 landing site by this evening. With a small telescope just beneath the center of the moon and near the terminator is one of my favorite craters Theophilus with its well-defined central peak. It’s kind of middle-aged for craters on the moon from 1 to 3 billion years old. It’s in much better shape than the crater Cyrillus of nearly the same size that it partially overlaps, which is thought to be at least a billion years older and shows it.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon at 9 p.m. March 6, 2014 highlighting the Sea of Tranquility the Apollo 11 landing site (approximate) and the crater Theophilus. Created using Virtual Moon Atlas.
Lunar craters Theophilus and Cyrillus. Credit: NASA/LRO mapped onto Virtual Moon Atlas.
06/13/2013 – Ephemeris – The moon tonight and the crater Theophilus
Ephemeris for Thursday, June 13th. Today the sun will be up for 15 hours and 31 minutes, setting at 9:28. The moon, 3 days before first quarter, will set at 12:23 tomorrow morning. Tomorrow the sun will rise at 5:56.
The 5 day old crescent moon reveals to a small telescope, a trio of large craters on the edge of the moon’s terminator or sunrise line. The best of these is on top Theophilus, a perfectly circular 61 mile diameter crater with a prominent central peak. It’s a little late for it tonight but sometimes when the terminator is crossing the crater, the floor is dark and the central peak catches the morning sunlight. The other two craters won’t be completely in sunlight tonight. Theophilus is a couple of hundred miles south of the Apollo 11 landing site in the Sea of Tranquility, That sea will be completely in sunlight tomorrow night. The moon is a great celestial object to view with any telescope.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The moon at 10 p.m. on June 13, 2013. In our skies the moon will be rotated some 30-40 degrees clockwise. Created using Virtual Moon Atlas.
Note: Due to some familial concerns yesterday, this post is a bit late.
11/14/11 – Ephemeris – The moon tonight
Monday, November 14th. The sun will rise at 7:37. It’ll be up for 9 hours and 38 minutes, setting at 5:15. The moon, half way from full to last quarter, will rise at 8:19 this evening.
The moon will be a waning gibbous phase tonight. The terminator is now the sunset line sweeping slowly across the moon. To the unaided eye or binoculars darkness will be falling across the Sea of Tranquility on the moon’s equator and will start to cross the Sea of Serenity above it. Below Tranquility is of my favorite craters Theophilus with its central peak will again stand out in shadows. It won’t be very close to the terminator tonight, but by tomorrow night it will be in the moon’s night and gone from our sight. The moon’s days and nights last nearly 15 days each. We are lucky to have a large satellite orbiting the earth. We may never know how important the role it had to play in establishing life on the earth.
* Times, as always are for the Traverse City/Interlochen area of Michigan.
Addendum
Waning Gibbous Moon 11/14/11 9 p.m. Created with Virtial Moon Atlas.
Bob Moler's Ephemeris Blog 