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Archive for the ‘The Moon’ Category

06/09/2017 – Ephemeris – Watch the mini moon rise tonight

June 9, 2017 1 comment

Ephemeris for Friday, June 9th. Today the Sun will be up for 15 hours and 29 minutes, setting at 9:26, and it will rise tomorrow at 5:57. The Moon, at full today, will rise at 9:26 this evening.

In recent years we’ve talked about the super moon, when the full Moon appears especially large because it’s at perigee, or closest to the Earth at that time. Well tonight’s full Moon will be a the opposite, a mini Moon. The Moon reached apogee, its farthest from the Earth in it’s orbit at 6:21 last night, and 15 hours later, at 9:10 this morning the Moon was full. However I bet that when the Moon rises tonight that it will appear just as big as it always does, especially if you forget that it’s supposed to be a mini moon. The Moon is in an elliptical orbit of the Earth that this month varies from 252,500 miles (406,400 km) yesterday down to 222,400 miles (357,900 km) on the 23rd. Thanks to the Sun, and especially Jupiter and Venus, those distances change a bit every month. Tonight Saturn will be seen just below the moon.

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

Addendum

Mini Moon and Super Moon

Mini Moon and Super Moon for 2017. Created using Cartes du Ciel (Sky Charts).

06/06/2017 – Ephemeris – Where did the Moon come from?

June 6, 2017 1 comment

Ephemeris for Tuesday, June 6th. Today the Sun will be up for 15 hours and 26 minutes, setting at 9:24, and it will rise tomorrow at 5:57. The Moon, 3 days before full, will set at 5:10 tomorrow morning.

The origin of the Moon is a question that has vexed astronomers for years. Did it break off the molten Earth like a cell dividing? Was it captured by passing too close to the Earth? Neither is satisfactory. Chemical elements have different isotopes depending on the number of neutrons in their nucleus. The rocks brought back by the Apollo astronauts show that the isotopes of the elements in the rocks is that same as for the Earth. We know that Mars and the asteroids have different isotope ratios. The hypothesis that seems most likely is that another planet, the size of Mars collided with the 100 million year old Earth in a glancing blow that gave rise to a disk of material that eventually coalesced into the Moon.

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

Addendum

Collision spawning the Moon

The hypothetical collision of a Mars sized body with the young Earth. Credit: Joe Tucciarone via NASA

05/26/2017 – Ephemeris – Can you spot the extremely young Moon tonight?

May 26, 2017 1 comment

Ephemeris for Friday, May 26th.  Today the Sun will be up for 15 hours and 11 minutes, setting at 9:15, and it will rise tomorrow at 6:03.  The Moon, 1 day past new, will set at 10:16 this evening.

It’s spring and a great time to see if you can spot the young moon.  The official time when the moon was new was 3:44 p.m. yesterday afternoon (19:44 UT 25 May 2017), which would make the moon a bit less than 31 hours old if spotted before it sets an hour after the Sun.  This requires crystal clear skies and a very low northwestern horizon.  Binoculars are a definite help.  Spotting the earliest moon after new moon is one of the challenges amateur astronomers pit their observing skills with.  Another is the Messier Marathon, in which one tries to observe all 110 of Charles Messier’s catalog entries of dim objects on a single night, which is theoretically possible around March 24th.

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

Addendum

Young Moon

A 39 hour old Moon with Jupiter taken by Greg Hogan on September 2, 2016.

I got this from EarthSky.org.  Here’s a search I made of the young moon that has some other images:  http://earthsky.org/?s=young+moon

05/17/2017 – Ephemeris – Let’s look at the bright planets for this week

May 17, 2017 Comments off

Ephemeris for Wednesday, May 17th.  Today the Sun will be up for 14 hours and 54 minutes, setting at 9:06, and it will rise tomorrow at 6:11.  The Moon, 1 day before last quarter, will rise at 2:20 tomorrow morning.

Let’s take our weekly look at the bright planets.  Mars is still in the west-northwest after sunset and fading.  It appears under the left edge of the constellation Auriga.  It will set at 10:54 p.m.  Dominating the evening sky now is Jupiter in the south-southeast.  The bright blue-white star Spica is seen below and left of it.   In even the smallest telescopes Jupiter’s four largest moons can be seen.  They shift positions night from to night and sometimes even as you watch.  Jupiter will set at 4:42 a.m.  At 5:30 a.m. both Saturn and Venus will be in the morning twilight.  Saturn will be low in the south-southwest.  It will rise in the east-southeast at 11:14 p.m.  Brilliant Venus will be low in the east tomorrow morning after rising at 4:27 a.m.

For us Mercury, at greatest western elongation of 25.8°will be on the horizon at 5:30, but those south of the equator it will be well placed for viewing in the morning.

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

Addendum

Evening planets

Mars and Jupiter with the spring constellations in the fading twilight at 10 p.m., May 17, 2017. Created using Stellarium.

Jupiter nd moons

Jupiter and its four Galilean moons as they might be seen in a telescope at 10 p.,. May 17, 2017. Created using Cartes du Ciel (Sky Charts).

Morning planets

Venus, Saturn and the Moon at 5:30 a.m. May 18, 2017. Created using Stellarium. Click on the image to expand.

Saturn and moons

Saturn and its brightest moons at 5:30 a.m. May 18, 2017. This is displayed at the same scale/magnification as the Jupiter image above. Created using Cartes du Ciel (Sky Charts).

Binocular moon

The Moon as it might be seen in binoculars at 5:30 a.m., May 18, 2017. Created using Stellarium.

Telesvopic Venus

Venus as seen through a telescope at 5:30 a.m. May 18, 2017. This is displayed at a larger scale/magnification than the Jupiter and Saturn images above. Created using Stellarium.

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on May 17, 2017. The night ends on the left with sunrise on May 18. Click on the image to enlarge. Created using my LookingUp program.

05/08/2017 – Ephemeris – Europe and the Chinese are talking about a joint Moon village

May 8, 2017 2 comments

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

Moon base

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

May 2, 2017 1 comment

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

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

April 3, 2017 Comments off

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

Thee Moon's Phases

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.