Archive
05/08/2017 – Ephemeris – Europe and the Chinese are talking about a joint Moon village
Ephemeris for Monday, May 8th. The Sun rises at 6:22. It’ll be up for 14 hours and 33 minutes, setting at 8:55. The Moon, 2 days before full, will set at 6:07 tomorrow morning.
NASA, so far has no plans to return to the Moon to set up a base in preparation to heading out to Mars or an asteroid. That could change. The United States has a problem with long-term goals and planning with a change in administration every 4 or 8 years. The European Space Agency, and the China National Space Administration have no such problem. And it seems that these two entities are talking about together creating a Moon Village. The raw resource that they may hope to mine is Helium 3, which can be used in earthly fusion reactors to produce power. Helium 3 comes via the solar wind from the Sun. A base could be setup at the south pole of the Moon, which has virtually no axial tilt to receive perpetual sunlight for power and water from eternally shadowed crater bottoms.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Artist visualization of a near polar moon base. Credits: ESA/Foster + Partners via Universe Today
I got this story from Universe Today: https://www.universetoday.com/135270/europe-china-discuss-moonbase-partnership/
05/02/2017 – Ephemeris – Puzzling out the Moon’s history
Ephemeris for Tuesday, May 2nd. The Sun rises at 6:30. It’ll be up for 14 hours and 17 minutes, setting at 8:48. The Moon, at first quarter today, will set at 3:06 tomorrow morning.
The Moon will be at exactly first quarter at 10:47 p.m., so it should be split exactly in half by the sunrise line or terminator. On the illuminated face of the Moon can be seen the dark gray spots called seas. In dating the moon rocks brought back by the Apollo astronauts the dates tell the amount of time since the rocks were molten due to collisions. The dates turn out to give clues to when the seas were formed, because they are actually large impact craters, which were filled in by the lava from the moon’s interior. The oldest rocks on the Moon are 4.5 billion years old, dating from the formation of the Moon. There’s another group about 3.9 billion years old dating to when many of the seas were formed in a cataclysm called the late heavy bombardment.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
First quarter Moon with key to the lunar seas. Created using Stellarium.
Sym Latin Name English Name Age A Mare Serenitatis Sea of Serenity 3.85 to 3.92 billion years B Mare Tranquillitatis Sea of Tranquility 3.92 to 4.55 billion years C Mare Nectaris Sea of Nectar 3.85 to 3.92 billion years D Mare Fecunditatis Sea of Fertility 3.92 to 4.55 billion years E Mare Crisium Sea of Crises 3.85 to 3.92 billion years F Mare Frigoris Sea of Cold 3.85 to 4.55 billion years
Data are from Virtual Moon Atlas
04/03/2017 – Ephemeris – A two bit* Moon today
Ephemeris for Monday, April 3rd. The Sun will rise at 7:19. It’ll be up for 12 hours and 53 minutes, setting at 8:12. The Moon, at first quarter today, will set at 3:38 tomorrow morning.
The Moon will be at exactly first quarter at 2:12 this afternoon (18:12 UT). By this evening for us the terminator line, which is the sunrise line on the Moon as the Moon’s phase waxes will be bowed to the left a bit. The names of the primary phases of the Moon are a bit odd. The quarter moons are named for their positions one quarter or 90 degrees from the Sun. The full moon describes it appearance as fully illuminated. New moon is odd too. To the Jews and the Arabs the New moon was the name for the first sighting of the crescent Moon after it disappeared from the morning sky. Astronomers use that term today for when the Moon is in conjunction with the Sun, day zero of a lunation or lunar month, about a day before its first appearance in the evening.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* If “two bit” is foreign to you. It dates back to US colonial times when the most prevalent coin around was the Spanish Dollar, also known as a piece of eight. A quarter of that was two bits, 25 cents in modern parlance. It lives on in the tune and knock sequence “Shave and a haircut, two bits” or five rapid knocks a pause and two more. See the movie “Who Framed Roger Rabbit?”.
Addendum
This is the best diagram of the Moon’s phases and how the it appears from the Earth. Credit http://planetfacts.org/phases-of-the-moon/ which I recommend.
However I do not like the label Dark Side. It is simply the night side. The Far Side is what many people mistakenly call the dark side, because we can never see it from the Earth. However the far side sees more sunlight than the near side. One, it is never darkened by an eclipse of the Moon, because it’s night-time there normally at that time. Two, at new moon it is fully facing the Sun, and also a quarter of a million miles closer to the Sun than the Earth is. So how can it be the dark side. Really. Come on people.
03/07/2017 – Ephemeris – The Moon tonight – the crater Copernicus
Ephemeris for Tuesday, March 7th. The Sun will rise at 7:08. It’ll be up for 11 hours and 29 minutes, setting at 6:38. The Moon, 2 days past first quarter, will set at 4:39 tomorrow morning.
Looking at the Moon tonight the brightest feature on the left side of the moon is the big splash mark left by the impact that created the crater Copernicus. The proper term is ejecta blanket that can be noticed by the naked eye or binoculars. Although it is most visible during full moon, because it is really made of small craters that are most visible when we see them from the direction of the Sun, so they are not shadow filled and brighter than normal. Copernicus is on the south edge of a great lava plain called Mare Imbrium, the Sea of Showers. There’s a large crater on the north edge named after the Greek philosopher Plato. At the upper left edge is the Laplace promontory the point of the Bay of Rainbows to be revealed tomorrow night.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon featuring Copernicus, Plato, Laplace Promontory and Mare Imbrium at 9 p.m., March 7, 2017. Created using Virtual Moon Atlas.
02/14/2017 – Ephemeris – Is the Moon waxing or waning?
Ephemeris for St Valentine’s Day, Tuesday, February 14th. The Sun will rise at 7:43. It’ll be up for 10 hours and 26 minutes, setting at 6:10. The Moon, half way from full to last quarter, will rise at 10:18 this evening.
This morning the waning gibbous moon will be a way to the right of the bright planet Jupiter which is in the southwest at 7 a.m. Tomorrow morning the Moon will appear above and right of Jupiter. My granddaughter is taking earth science in school now and is confused about when the Moon is waxing or waning. If it’s waxing it is getting fuller each night. If waning the Moon’s phase is getting thinner each night. But I told her that if you can see the Moon in the evening it’s waxing, and if you can see the Moon in the morning it’s waning. It works except around full Moon where you’d need a calendar for the full moon date or if it rises before or after sunset.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
A graphic explaining the Moon’s position with respect to the Earth and Sun (which is off the diagram to the right). The Moon orbits the Earth in a counterclockwise direction. Credit NASA/Bill Dunford.
02/06/2017 – Ephemeris – The Moon is at perigee today
Ephemeris for Monday, February 6th. The Sun will rise at 7:54. It’ll be up for 10 hours and 4 minutes, setting at 5:58. The Moon, 3 days past first quarter, will set at 4:56 tomorrow morning.
At 9 this morning the Moon will be at perigee, the closest it gets to the Earth in its current orbit of the Earth. Had the Moon been full it would be called a super-moon. The Moon isn’t just orbiting the Earth, but it is also pushed around by the Sun, which has a greater hold on he Moon than the Earth, but also by Jupiter and Venus, plus all the other objects in the solar system to a far lesser degree. You are not going to see it rise this afternoon at 1:48, so the big Moon on the horizon optical illusion doesn’t come into play. It will appear its highest at 9:21 this evening, some 63 degrees above the horizon. By then it will be some 3500 miles or so closer than when it’s on the horizon, because we’re on the Moon facing side of the Earth. Look up, there the Moon doesn’t really look very big at all, does it?
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon and the stars tonight at 9:21 p.m. Don’t be fooled by the size of the Moon. Here it appears 4 times its actual diameter, and 16 times its area in this image. It actually appears really small. But it will appear a lot bigger when it sets due to the horizon illusion. Created using Stellarium.
02/02/2017 – Ephemeris – Can you see the rabbit on the Moon?
Ephemeris for Ground Hog Day, Thursday, February 2nd. The Sun will rise at 7:59. It’ll be up for 9 hours and 53 minutes, setting at 5:53. The Moon, 1 day before first quarter, will set at 12:24 tomorrow morning.
The crescent Moon is in the southwestern sky. It is revealing a group of lunar seas, dark gray areas that portrays an upside down rabbit. From the top down are the seas Serenity as his body, the sea of Tranquility as his head. His two ears are different sizes, the larger is the Sea of Fertility, and the smaller ear is the Sea of Nectar. All of these seas seem to be connected. The unconnected sea is the Sea of Crises, a pretty good symbol for our times, but unconnected to our upside down rabbit. One word about the Latin names for these. The Latin name for a sea is Mare, spelled like the female horse but pronounced Mar-ē. The plural is Maria, spelled like the lady’s name but pronounced with the accent on the first syllable.
At 5:11 am EDT (10:11 UT) Venus and Mars will appear at their closest to each other at 5.4° or about 11 Moon diameters. From then on, Venus will back away. That is the Sun will overtake Venus faster than it will Mars. They will eventually pass each other on October 5, 2017.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
An animation showing how the rabbit in the Moon as might be seen tonight February 2, 2017, demonstrating my complete lack of artistic talent. Created from a Moon image from Stellarium, Overlay from Libreoffice Draw, and animated GIF from GIMP.
Search [rabbit in moon] in Google images for more artistic examples.
01/24/2017 – Ephemeris – The Moon is near Saturn this morning
Ephemeris for Tuesday, January 24th. The Sun will rise at 8:09. It’ll be up for 9 hours and 31 minutes, setting at 5:40. The Moon, 3 days before new, will rise at 6:08 tomorrow morning.
This morning look low in the southeast to see the thin crescent Moon with the planet Saturn below and to the right. The Moon passed Saturn a little after they rose. Saturn is quite far south in our skies, almost as far south as the Sun was on the winter solstice on December 21st. It will take a while to rise high enough in deep twilight or darkness for good views with a telescope. When Saturn or any planet is low on the horizon we are looking at it through a lot of our atmosphere. Beside draining about half its brightness that atmospheric motions make the planet fuzzy in telescopes. Yes, you can still see the rings, but the gaps on each end between the rings and the planet may not be distinct, and its large moon Titan may not be visible at all.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The morning planets and the Moon at 7 a.m. this morning, January 24th. Because planetarium programs don’t show a thin crescent very well, I’ve enlarged the Moon by a factor of 4 times to make the Moon show up at all. Click on the image to enlarge. Created using Stellarium.
12/21/2016 – Ephemeris – A look at the bright planets at the start of winter
Ephemeris for the winter solstice Wednesday, December 21st. The Sun will rise at 8:17. It’ll be up for 8 hours and 48 minutes, setting at 5:05. The Moon, 1 day past last quarter, will rise at 1:46 tomorrow morning.
Let’s look at the naked eye planets now that it’s officially winter as of 5:45 a.m. In the east-southeast before 7:30 these mornings. Jupiter can be glimpsed in the morning twilight. Jupiter will rise tomorrow at 2:16 a.m. and will appear below the Moon. Venus and Mars are in the evening sky. At 6 p.m. these planets will be seen in the southwest and low in the sky. Venus is unmistakable as the brilliant evening star, Mars will be above and left of it. Venus will set at 8:46. Mars will set at 10:12. Mars’ setting time hasn’t changed much in the last 2 months. Venus is slowly heading northward for the rest of it’s evening appearance, and is moving higher in the sky, and is closing in on it’s greatest eastern elongation from the Sun.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus and Mars in the evening twilight of about an hour after sunset. 6 p.m. December 21, 2016. Created using Stellarium.
Venus as it might be seen in a telescope at 6 p.m. December 21, 2016. Created using Stellarium.
Jupiter and the Moon at 7 a.m. December 22, 2016. Created using Stellarium.
The Moon as it might appear in binoculars at 7 a.m. December 22, 2016. Created using Stellarium.
Jupiter and its Galilean moons at 7 a.m. December 22, 2016. Io is behind Jupiter at this time, however it will clear the planet by 7:38 a.m. EST (12:38 UT). Created using Cartes du Ciel (Sky Charts).
Update 8:10 a.m.
Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on December 21, 2016. The night ends on the left with sunrise on December 22. Click on image to enlarge. Created using my LookingUp program.
12/07/2016 – Ephemeris – Where are the bright planets
Ephemeris for Wednesday, December 7th*. The Sun will rise at 8:06. It’ll be up for 8 hours and 55 minutes, setting at 5:02. The Moon, at first quarter today, will set at 1:16 tomorrow morning.
In the east-southeast before 7:30 these mornings. Jupiter can be glimpsed in the morning twilight. Jupiter will rise tomorrow at 3:01 a.m. We are approaching Jupiter as it appears to move away from the Sun. We will pass it on April 7th next year. Venus and Mars are in the evening sky. At 6 p.m. these planets will be seen in the southwest and low in the sky. Venus will be the lower and brighter of the two, Mars will be higher to the left. Venus will set at 8:14. Mars will hang on a bit longer and will set at 10:10. Mars’ setting time hasn’t changed much in the last month and a half. It’s losing to the Sun by only a little bit each day. Venus is slowly heading northward for the rest of it’s evening appearance, and is moving higher in the sky.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* 75th anniversary of the attack on Pearl Harbor. I was only 3 days old at the time, so had nothing to do with it.
Addendum
Venus, Mars and the Moon at 6 p.m., December 7, 2016. This is approximately one hour after sunset. Click on image to enlarge. Created using Stellarium.
A closeup of the Moon at 6 p.m., December 7, 2016. Created using Stellarium.
Jupiter and a preview of spring constellations at 6:30 a.m. December 8, 2016. Click on image to enlarge. Created using Stellarium.
Jupiter and moons at 6:30 a.m. December 8, 2016. Europa is in Jupiter’s shadow at this time. It will disappear in its shadow at 4:46 a.m. (9:46 UT). Image created using Cartes du Ciel. Note that Europa was on the image, but was removed. Stellarium had it right, but I prefer Cartes’ rendering.
Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on December 7, 2016. The night ends on the left with sunrise on December 8. Click on image to enlarge. Created using my LookingUp program.
Note that Saturn is practically plotted on top of the Sun. It will be in conjunction with the Sun on the 10th. After that it will enter the morning sky.
Bob Moler's Ephemeris Blog 