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02/22/2019 – Ephemeris – Orion is a hard luck hero

February 22, 2019 Leave a comment

Ephemeris for Friday, February 22nd. Today the Sun will be up for 10 hours and 48 minutes, setting at 6:20, and it will rise tomorrow at 7:30. The Moon, 3 days past full, will rise at 10:19 this evening.

We come back to the central constellation of the winter sky Orion the hunter, holding out in the south-southwest at 9 p.m. with his three stars of his belt in a straight line, with his shoulder stars above and knees below. In one Greek story he was killed by the sting of a scorpion so the gods made sure the rising of the constellation Scorpius would chase him out of the sky to the west. To the Greeks he was a hapless hero. Orion is mentioned in the Bible in the book of Job. The name for Orion in Hebrew is Kesil, meaning “Fool”. To the native peoples around the Great Lakes, the stars here are those of the Winter Maker, who stretches his arms from Aldebaran in Taurus to Procyon in Canis Minor. When he rides high the evening sky it is indeed winter.

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

Addendum

Orion

Orion as he is seen tonight at 9 p.m. February 22, 2019. Created using Stellarium.

Scorpius chases Orion from the skies

Scorpius, rising in the southeast, chases Orion, setting in the west, from the skies. February 23, at 2:44 a.m. any year.

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02/21/2019 – Ephemeris – Greenspire School’s STEM Night is tonight

February 21, 2019 Leave a comment

Ephemeris for Thursday, February 21st. Today the Sun will be up for 10 hours and 45 minutes, setting at 6:19, and it will rise tomorrow at 7:32. The Moon, 2 days past full, will rise at 9:05 this evening.

Tonight the Greenspire School is sponsoring its annual STEM Night from 6 to 8 p.m. at the school on Red Drive at the Grand Traverse Commons. Red Drive is a block west of Silver Drive that connects to Silver Lake Road at Franke Road. STEM is an acronym for Science, Technology, Engineering and Math. The Grand Traverse Astronomical Society will be there for the sixth year with Gary Carlisle finding out what comets are made of by helping the kids create dry ice comets. We’ll have other exhibits too, and telescope kits to raffle off. Other exhibitors have hands on activities in science, technology, engineering and mathematics for the whole family. There’s also cookies and hot chocolate.

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

Addendum

STEM Night

Grand Traverse Astronomical Society members at STEM Night. Credit: Eileen Carlisle.

02/20/2019 – Ephemeris – Theoretical all 5 bright planets are now visible

February 20, 2019 Leave a comment

Ephemeris for Wednesday, February 20th. Today the Sun will be up for 10 hours and 42 minutes, setting at 6:18, and it will rise tomorrow at 7:34. The Moon, 1 day past full, will rise at 7:47 this evening.

Let’s look at the planets for this week. We have two evening planets visible now. Tiny and elusive Mercury should be visible low in the west for about a half hour after 7 p.m. It should be visible for a little over a week. Binoculars are a big help in spotting it. Mars will be in the southwestern sky this evening and will set at 11:46 p.m. In the morning sky we have Jupiter which will rise tomorrow at 3:32 a.m. It is second to Venus in brightness. Saturn will be next to rise at 5:22 a.m. It is just to the right of Venus which will rise at 5:29 a.m. tomorrow. In small telescopes Saturn will show its rings and Venus will show a small slightly gibbous moon shape which will shrink and grow more full over the next months

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

Addendum

 

Evening planets

Mars, Mercury and bright stars in twilight at 7 p.m. February 20, 2019. Created using Stellarium.

Morning planets

Morning planets and the Moon at 6:30 a.m. February 21, 2019. Click on the image to enlarge. created using Stellarium.

Binocular Moon

The waning gibbous Moon as it should appear tomorrow morning with binoculars. Created using Stellarium.

Telescopic planets

Jupiter, Saturn and Venus with the same magnification at 6:30 a.m. tomorrow morning February 21, 2019. See the table of Jupiter moon events tomorrow morning. Created using Cartes du Ciel (Sky Charts).

Satellite Event Date UT EST Notes
Ganymede Occultation start 21 Feb 2019 07:05:00 AM 2:05 a.m. Not visible from Michigan
Europa Shadow start 21 Feb 2019 08:36:00 AM 3:36 a.m.
Ganymede Occultation end 21 Feb 2019 09:15:00 AM 4:15 a.m.
Europa Transit start 21 Feb 2019 10:57:00 AM 5:57 a.m.
Europa Shadow end 21 Feb 2019 10:58:00 AM 5:58 a.m.
Io Eclipse start 21 Feb 2019 11:49:00 AM 6:49 a.m.
Europa Transit end 21 Feb 2019 01:21:00 PM 8:27 a.m. Not visible from Michigan

Jupiter satellite events are from https://www.projectpluto.com/jevent.htm

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 February 20, 2019. The night ends on the left with sunrise on the 21st. Click on the image to enlarge. Created using my LookingUp program.

02/19/2019 – Ephemeris – The Moon ain’t just super near the horizon

February 19, 2019 Leave a comment

Ephemeris for Tuesday, February 19th. Today the Sun will be up for 10 hours and 39 minutes, setting at 6:16, and it will rise tomorrow at 7:35. The Moon, at full today, will rise at 6:28 this evening.

Tonight we will have a super full Moon. It will be the closest full moon of the year, not that you could really tell. The full moon, or waning moon looks large near the horizon when it’s rising. The same is true of waxing moons setting. The same is true of sunrises and sunsets. However if you look closely at the rising or setting Moon or Sun right at the horizon you will notice that it appears a bit squashed. This is due to atmospheric refraction or bending of the light which makes the them appear higher in the sky than they actually are. It is most pronounced near the horizon. In fact by the time the Sun appears to touch the horizon, it is already completely below the horizon, and would appear be if we didn’t have an atmosphere.

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

Addendum

Suashed Moon at moonrise

The Moon just after moonrise 1 day past full. The Moon appears squashed vertically by about 10% compared to circumscribed circle. Credit Eileen Carlisle.

Atmospheric Refraction

How the atmosphere bends the light of the Sun or Moon rising or setting to appear higher than it actually is. Credit Francisco Javier Blanco González, 2017

 

02/18/2019 – Ephemeris – Super Moon, super math

February 18, 2019 Comments off

Ephemeris for President’s Day, Monday, February 18th. Today the Sun will be up for 10 hours and 36 minutes, setting at 6:15, and it will rise tomorrow at 7:37. The Moon, 1 day before full, will set at 7:52 tomorrow morning.

Ready for some math this morning? This will be easy, because you will only have to think about it. Let’s say the Earth’s radius is 4,000 miles.  That is pretty close to its actual value. OK, it is 3961 miles (6,378 km) at the equator. The Earth is nearly spherical. At 4 this morning the Moon passed perigee, its closest point to the Earth, making tomorrow’s full moon a super-moon. Let’s say it will be at today’s distance of 221,600 miles (356,800 km). That’s center to center. At moon rise or moon set the Moon is near that center to center distance, but if it moves overhead it’s 4,000 miles closer because we are on the Earth facing the Moon. Even though the Moon looks smaller than when it appears on the horizon. It’s an optical illusion that the Moon appears larger when it is rising. Super moon or not.

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

Addendum

The difference in the Moon's distance at rising (or setting) versus when it is overhead

This illustrates the difference in the Moon’s distance at rising (or setting) versus when it is overhead. BTW today’s perigee puts the Moon at only 56 Earth radii from the Earth. The illustration is mine.

02/15/2019 – Ephemeris – Venus will pass Saturn Monday morning

February 15, 2019 Comments off

Ephemeris for Friday, February 15th. Today the Sun will be up for 10 hours and 27 minutes, setting at 6:11, and it will rise tomorrow at 7:41. The Moon, 3 days past first quarter, will set at 5:21 tomorrow morning.

The planets Venus and Saturn cross paths in conjunction next Monday morning at about 9 a.m. This weekend you can watch them inch closer and closer together before sunrise. Venus is a whole lot brighter than Saturn and will be seen to move above Saturn Monday morning. As I noted on the Jupiter-Venus conjunction three and a half weeks ago, these two planets are nowhere close to each other. Venus will be 92.9 million miles (149.6 million km) away, about as far as the Sun. Saturn will be a bit over 1 billion miles (1.612 billion km) away, making Saturn almost 11 times farther away as Venus. The only effect this conjunction will have on me is that it will be a cool sight to see those two planets together in the sky.

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

Addendum

Venus-Saturn Conjunction

Daily animation of the morning planets featuring the Venus-Saturn conjunction at 6:30 a.m. on February 16th through 19th 2019. Click on the image to enlarge. Created using Stellarium and GIMP.

02/14/2019 – Ephemeris – How about a heart shaped nebula for Valentine’s Day

February 14, 2019 Comments off

Ephemeris for St Valentine’s Day, Thursday, February 14th. Today the Sun will be up for 10 hours and 24 minutes, setting at 6:09, and it will rise tomorrow at 7:43. The Moon, 2 days past first quarter, will set at 4:18 tomorrow morning.

Nebulae, or clouds of gas and dust, sometimes have shapes when seen in telescopes that remind us of familiar objects, like the Horsehead nebula, the North American Nebula, the Saturn Nebula and so on. So on Valentine’s day I’ll direct you to nebula IC 1805, the Heart Nebula. In the center of the nebula is a nest of stars, many of which are massive with strong stellar winds that blew out the original birth cloud which collided into other clouds of gas to shape it into a rough heart from our vantage point. The color for Valentine’s day is red. Red is the nebula’s true color, it’s the primary color the element hydrogen gives off when excited. In this case excited by those hot young stars in its center.

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

Addendum

Heart Nebula

IC 1805 (Heart Nebula) Credit: s58y [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

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