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10/18/2013 – Ephemeris – Penumbral lunar eclipse tonight
Ephemeris for Friday, October 18th. The sun will rise at 8:01. It’ll be up for 10 hours and 50 minutes, setting at 6:52. The Moon, at full today is the full Hunters Moon, will rise at 6:41 this evening.
There will be a penumbral eclipse of the moon tonight as the moon rises. This is a special case of a partial eclipse, in that the moon dips only into the earth outer shadow, where sunlight to it is only partially blocked by the earth. To the casual observer nothing appears to be happening, but near mid eclipse the bottom right part of the moon will appear to have a dusky appearance, a 5 o’clock shadow, so to speak, which is best seen wearing sun glasses to cut the bright glare of the full moon. That mid eclipse point will occur at 7:50 this evening. The moon will be in eclipse as it rises, and the eclipse will officially end at 9:52 p.m., though the shadow effect will be long gone by that time.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Penumbral Eclipse of October 18-19. Times on this chart are Universal Time. The times in the post above are Eastern Daylight Time. Credit: H M Nautical Almanac Office, UK.
Note: The moon has to dip into the Umbra for the eclipse to be a partial or total eclipse. In the world map above Michigan is in the partially shaded part of the diagram, where the eclipse starts before the moon rises. The darker shaded portions of the earth cannot see the eclipse at all.
10/17/2013 – Ephemeris – The lonely star
Ephemeris for Thursday, October 17th. The sun will rise at 8:00. It’ll be up for 10 hours and 53 minutes, setting at 6:54. The moon, 1 day before full, will set at 7:37 tomorrow morning.
There’s a bright star that appears for only seven and a half hours on autumn evenings. It’s appearance, low in the southeast at 10 p.m., is a clear indication of the autumn season. The star’s name is Fomalhaut, which means fish’s mouth. That’s fitting because it’s in the constellation of Piscis Austrinus, the southern fish. At our latitude it’s kind of the fish that got away, because Fomalhaut appears to be quite alone low in the sky. The dimness of the constellation’s other stars and location close to the horizon make the faint stars hard to spot. The earth’s thick atmosphere near the horizon reduces their brightness by a factor of two or more, so Fomalhaut, one of the brightest stars in the sky, keeps a lonely vigil in the south.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The bright star Fomalhaut all alone at 9 p.m. Created using Stellarium.
10/16/2013 – Ephemeris – Where are the bright planets and Comet ISON this week
Ephemeris for Wednesday, October 16th. The sun will rise at 7:59. It’ll be up for 10 hours and 56 minutes, setting at 6:55. The moon, 2 days before full, will set at 6:30 tomorrow morning.
Time again to check out the bright planets. Venus is brilliant in the west southwest after sunset it will set at 8:46 p.m.. We are losing Saturn in the sun’s glare for a few months. The rest of the planetary action will be in the morning sky, though the giant planet Jupiter will rise before midnight at 11:47 a.m. in the east northeast. It’s cruising against the stars of Gemini now. By 6 a.m it will be high in the southeast, the brightest object in that direction. Mars will rise at 3:19 a.m. also in the east northeast. It’s near Leo’s brightest star Regulus at the bottom of the constellation’s backward question mark. It’s in the east at 6 a.m. Comet ISON is about two moon width’s to the upper left of Mars, but the bright moon will interfere with spotting it.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus low in the west southwest at 7:45 p.m. on October 16, 2013. Created using Stellarium.
Jupiter and Mars with the winter stars and constellations at 6 a.m., October 17, 2013. Created using Stellarium.
Mars and Comet ISON at 6 a.m. from October 17 to October 23, 2013. Star magnitude limit is 12. Created using Sky Charts (Cartes du Ciel)
10/15/2013 – Ephemeris – Correction to last Thursday’s Comet ISON program
Ephemeris for Tuesday, October 15th. The sun will rise at 7:58. It’ll be up for 10 hours and 59 minutes, setting at 6:57. The moon, 3 days before full, will set at 5:21 tomorrow morning.
Last week I went out to verify the statement that Comet ISON was visible in binoculars that I talked about last Thursday. That turned out to be incorrect. After two failed attempts last Tuesday and Wednesday mornings from my back yard. I had to find a darker location to out flank Traverse City and try to spot the comet with my 11 inch telescope. The comet turned out to be a faint smudge in the indicated spot. The sky wasn’t even dark in that direction, almost due east due to zodiacal light, visible on autumn mornings due to dust in the inner solar system. Zodiacal light is usually hard to spot until it becomes a nuisance. Advanced amateurs have indeed photographed it, tail and all, but visually the comet isn’t much at this stage.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Comet ISON and Mars at 6 a.m. for 7 days starting October 10, 2013. Created using SkyCharts (Cartes du Ciel).
I’ll have a new weekly chart tomorrow. Mars and Comet ISON are sliding past Regulus now. See spaceweather.com for images of Comet ISON. By the end of this week the Moon’s light will interfere.
10/14/2013 – Ephemeris – Columbus greatest and luckiest mistake
Ephemeris for Columbus Day, Monday, October 14th. The sun will rise at 7:56. It’ll be up for 11 hours and 2 minutes, setting at 6:59. The moon, 3 days past first quarter, will set at 4:12 tomorrow morning.
Today we celebrate Christopher Columbus’ big mistake. Mistake? Yes, mistake. Back in 1492 anyone with any education at all knew the earth was round. It was known since the Greek mathematician and geographer Eratosthenes calculated the circumference in the 3rd century BC. Columbus error was in misjudging its size. Columbus though the earth was only 18 thousand miles in circumference, which would put the east coast of Asia 3,000 miles west of the Spanish coast. Most academics held the circumference was nearer 25,000 miles, the correct value, putting Asia some 10,000 miles out. Columbus was very lucky that there was a continent in between. The native peoples, however, were not so lucky.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
10/11/2013 – Ephemeris – Tomorrow night is International Observe the Moon Night
Ephemeris for Friday, October 11th. The sun will rise at 7:53. It’ll be up for 11 hours and 11 minutes, setting at 7:04. The moon, at first quarter today, will set at 12:41 tomorrow morning.
Tomorrow night the Grand Traverse Astronomical Society (GTAS) and the NMC Astronomy Club will split forces. The NMC Astronomy Club will host the Star party at the Northwestern Michigan College’s Observatory starting at 9 p.m., while the Sidewalk Astronomers contingent of the GTAS will be on the north side 200 block of Front Street in Traverse City, in front of the Orvis Streamside store, for the International Observe the Moon Night weather permitting. Weather permitting means it must not be completely overcast or raining. I like to view the moon at this phase, a day after first quarter for the variety of detail that’s visible on the moon’s surface. This is our usual location for Friday Night Live.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Map supplied by the International Observe the Moon Night. The crater marked Plato should be Archimedes. It’s actually the moon in the afternoon our time.
The moon at 9 p.m. October 12, 2013. The terminator progresses a bit more from the above moon chart revealing more details. Created using Virtual Moon Atlas.
10/10/2013 – Ephemeris – Comet ISON is becoming visible in binoculars
Ephemeris for Thursday, October 10th. The sun will rise at 7:51. It’ll be up for 11 hours and 14 minutes, setting at 7:06. The moon, 1 day before first quarter, will set at 11:34 this evening.
Comet ISON is finally bright enough to possibly spot in binoculars. It seems to be between 10th and 11th magnitude, at the very limit of a pair of binoculars. Since it’s physically close to Mars, it’s close to Mars in our sky. Tomorrow morning it will be less than a binocular’s field of view to the upper left of Mars. Also don’t confuse Mars with the brighter star Regulus below Mars. In color photographs Comet ISON is showing a green coma or head a sign that the nucleus is spewing, among other things, cyanogen, a poison gas and/or diatomic carbon. Don’t worry, Comet ISON will not get anywhere close to the earth. The last comet I saw with a green head was Comet Hyakutake which came within 10 million miles of the earth in 1996. The comet’s head is pretty much a vacuum. We’ve flown spacecraft through them before. It’s the dust grains we worry about.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Tuesday morning (Oct 8) I went out to try to spot Comet ISON with my 10X50 binoculars at 5:30 a.m. and was unsuccessful. I think I had two problems. First I am located 5 miles southwest of Traverse City, and though I had a good view to the east, I was hampered by the lights of the city. Also there may have been some zodiacal light. It’s the prime time for zodiacal light in the morning and the inbound comet is following close to the ecliptic line where the zodiac constellations reside. Wednesday morning I’m setting up my 11″ Dobsonian reflector. Let’s see what I can see.
Wednesday morning (Oct 9) I had my 11 inch Dobsonian trained on the comet’s location. But the light from Traverse City south was overpowering. Let’s see plan C is to go south to outflank Traverse City. We have a member of the Grand Traverse Astronomical Society who lives about 9 miles south of me. The only town he has to the east, in the direction of the comet is 9 1/2 miles, the little town of Kingsley. So that’s where I’m going tomorrow morning if it stays clear. It’s expected to be.
Comet ISON and Mars at 6 a.m. for 7 days starting October 10, 2013. Created using SkyCharts (Cartes du Ciel).
Don’t expect a tail. The head if Comet ISON will be hard enough to see. The yellow line is the ecliptic, the projection of the earth’s orbit on the sky. Most planet orbital planes lie close to the earth’s orbital plane, so are usually seen near it. The star marked α is Regulus the brightest star in the constellation of Leo, and about the brightness of Mars.
Spaceweather.com has images of the comet.
10/09/2013 – Ephemeris – The Bright planets and Comet ISON for this week
Ephemeris for Wednesday, October 9th. The sun will rise at 7:50. It’ll be up for 11 hours and 17 minutes, setting at 7:08. The moon, 2 days before first quarter, will set at 10:32 this evening.
Time again to check out the bright planets. Mercury has an unfavorable greatest elongation from the sun today. It’s too close to the horizon for all but the best observers to spot. Almost the same can be said of Saturn, right of and a bit below Venus tonight. Binoculars may be needed to it. Saturn will set at 8:15 while Venus will set at 8:50 p.m.. We are losing Saturn in the sun’s glare for a few months. The rest of the planetary action will be in the morning sky. The giant planet Jupiter will rise at 12:12 a.m. in the east northeast. It’s cruising against the stars of Gemini now. By 6 a.m it will be high in the southeast, the brightest object in that direction. Mars will rise at 3:25 a.m. also in the east northeast. It’s nearing Leo.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus, Saturn and the Moon in the west southwest at 8 p.m. October 9, 2013. Created using Stellarium.
Closeup of the moon. Created using Stellarium.
Jupiter and Mars with the winter stars and constellations at 6 a.m., October 10, 2013. Created using Stellarium.
Comet ISON and Mars at 6 a.m. for 7 days starting October 10, 2013. Created using SkyCharts (Cartes du Ciel).
Note that the comet is somewhat dimmer than predicted and barely visible in binoculars. The tail may not be visible except in photographs. I can’t really say since I haven’t seen it yet.
10/08/2013 – Ephemeris – Comet ISON spotted from Mars
Ephemeris for Tuesday, October 8th. The sun will rise at 7:49. It’ll be up for 11 hours and 20 minutes, setting at 7:09. The moon, 3 days before first quarter, will set at 9:36 this evening.
Tonight look in the southwest at 8 p.m. or so to see the crescent moon to the upper left of Venus. In other news last week Sunday the Mars Reconnaissance Orbiter took photographs of Comet ISON. These have been posted on the Internet. Google ISON Mars. The Satellite’s HiRISE camera wasn’t built for the task, and only revealed a faint blob of light. Earth bound amateur astronomers can do a lot better. The images are posted on the University of Arizona’s web site and are not affected by government shutdown. Any images of the comet from the Curiosity rover will have to wait until the shutdown is over to be posted. Operators of the Opportunity and Curiosity rovers are still at work since ongoing space operations are deemed essential.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
HiRISE images of Comet ISON on Sept. 29, 2013. Credit: NASA/JPL/University of Arizona.
The Draconid meteor shower peaks tonight
The Draconid meteor shower is lackluster most years with a handful of meteors an hour, and this is one of those. However every once and a while all heaven breaks loose. It’s related to Comet Giacobini-Zinner, a short period comet. The radiant is overhead in the early evening, so this is a rare meteor shower best seen in the evening rather than the morning sky.
Here’s a link to my post a couple of years ago (2011) about it including a finder chart: https://bobmoler.wordpress.com/2011/10/06/100611-ephemer…-meteor-shower/
For this year check out the site EarthSky.org and their take on the Draconids.
Draconid Meteor Shower Radiant
The red triangle delineates the Summer Triangle.
Bob Moler's Ephemeris Blog 