Archive
10/22/2012 – Ephemeris – Three prominent craters on the moon tonight
Ephemeris for Monday, October 22nd. The sun will rise at 8:07. It’ll be up for 10 hours and 38 minutes, setting at 6:45. The moon, 1 day past first quarter, will set at 1:45 tomorrow morning.
Tonight’s slightly gibbous moon will reveal at its terminator a line of three craters just below the center of the moon. The one closest to the center of the moon, and the largest is Ptolemaeus, names for Claudius Ptolemy 2nd century astronomer. The next crater is Alphonsus named after Alphonse X, 13th century king of Castille, and responsible for improved astronomical tables. Alphonsus has been the site of transient reddish hazes that soggest to som of volcanis activity, but it’s never been proven. It was the target of the last Ranger spacecraft that crashed onto the moon taking pictures all the way down. The third crater is Arzackel , named after an 11th century Arabian astronomer.
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 October 22, 2012. Created using Virtual Moon Atlas.
10/19/2012 – Ephemeris – Sky gazing opportunities in the Grand Traverse region.
Ephemeris for Friday, October 19th. The sun will rise at 8:03. It’ll be up for 10 hours and 46 minutes, setting at 6:50. The moon, 2 days before first quarter, will set at 10:20 this evening.
There are two chances for the public to observe the heavens this weekend. First is a Star Party at Northwestern Michigan College’s Rogers Observatory tomorrow night Saturday the 20th from 9 to 11 p.m.. The observatory is open rain or shine with a presentation, if its cloudy. Sunday the 21st the Grand Traverse Astronomical Society will hold its last Star Party of the year at Sleeping Bear Dunes National Lakeshore celebrating their 42nd anniversary. This event will run from 8 to 10 p.m. At the Pierce Stocking Scenic Drive at Stop 3, the Dunes Lookout. Parking for this event should be at Picnic Mountain just before stop 3. For both events we’ll have the first quarter moon, and wonders of the autumn and even summer skies.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
10/18/2012 – Ephemeris – Autumn wonders for binoculars or small telescope: The Alpha Persei Association
Ephemeris for Thursday, October 18th. The sun will rise at 8:02. It’ll be up for 10 hours and 49 minutes, setting at 6:52. The moon, half way from new to first quarter, will set at 9:17 this evening.
When is a star cluster not a star cluster? When it’s an association. That is when it has begun to dissipate because the gravitational force of the group cannot hold it together. The central stars of the Big Dipper belong to The Ursa Major Association. Below the W shaped constellation of Cassiopeia in the northeast at 9 or 10 p.m. Is the constellation of Per-seus or Pers-e-us as it is usually pronounced. Its brightest star is Mirfak with a designation of Alpha Persei. There are some stars there to the naked eye, but with binoculars there are a great many stars just below naked eye visibility. This is called the Alpha Persei association. The star groups I’ve talked about this week are just some of the wonders visible in a simple pair of binoculars.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The constellation Perseus. (Stellarium spells Alpha Persei Mirphak, not Mirfak. Star name spelling can be something variable.)
The constellation Perseus in the northeast at 10 p.m. on October 18, 2012. Created using Stellarium.
The Alpha Persei Association in a binocular view. Created using Stellarium.
10/17/2012 – Ephemeris – Autumn wonders for binoculars or small telescope: The Alpha Persei Association
Ephemeris for Wednesday, October 17th. The sun will rise at 8:00. It’ll be up for 10 hours and 52 minutes, setting at 6:53. The moon, 2 days past new, will set at 8:21 this evening.
Let’s see how many bright planets we can find this week. At 8 p.m. Mars can be seen low in the southwest approaching another red star Antares, whose name means rival of Mars. They will be closest in a few days. The moon will be nearby too. Mars will set at 8:45. The planetary action moves to later in the evening and the morning. Jupiter, will rise at 9:17 p.m. in the east northeast. It is located in the constellation of Taurus. It will transit or pass due south at 4:52 a.m. The last bright planet of the night is the morning star Venus which will rise at 4:44 a.m. also in the east. Venus is now below the hind end of Leo. The planets Venus and Jupiter and the winter constellations are a great sight for early risers. You can enjoy for a few more weeks without danger of frost bite.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars, Antares, and the moon at 7:50 p.m. on October 17, 2012. Created using Stellarium.
The moon at this scale is over exposed.
The actual phase of the moon in the chart above. Created using Stellarium.
The morning sky.
The morning skies including Jupiter and Venus at 6 a.m. on October 18, 2012. Created using Stellarium.
10/16/2012 – Ephemeris – Autumn wonders for binoculars or small telescope: The Pleiades
Ephemeris for Tuesday, October 16th. The sun will rise at 7:59. It’ll be up for 10 hours and 55 minutes, setting at 6:55. The moon, 1 day past new, will set at 7:33 this evening.
The most magnificent star cluster of the autumn sky is the Pleiades or Seven Sisters. At 10 p.m. It will appear as a close group of stars of a nebulous fuzz, depending your eyesight or sky conditions low in the east. It is the perfect binocular object, showing under good conditions a hundred more than the 7 brightest stars. Some mistake it for the Little Dipper because the stars do make a nearly handle less dipper. I tend to call it the Tiny Dipper. The stars in the Pleiades are less than half the age of the stars in the Double Cluster I talked about yesterday. The stars in the is cluster are about 100 million years old. Compared to the sun, these guys aren’t out of diapers yet. I’ll have lots more to to talk about the Pleiades as autumn wears on.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Pleiades, about what you’d see in binoculars.
Pleiades and Jupiter at 10 p.m. October 16, 2012. Created using Stellarium.
10/15/2012 – Ephemeris – Autumn wonders for binoculars or small telescope: The Double Cluster
Ephemeris for Monday, October 15th. The sun will rise at 7:58. It’ll be up for 10 hours and 58 minutes, setting at 6:57. The moon is new today, and won’t be visible.
This week we’ll be looking at some of the wonders of the autumn sky that might better be seen in binoculars or a small telescope. Tonight we turn our attention to the Double Cluster, a fine pair of star clusters just below the W of the constellation of Cassiopeia the queen located in the northeast. Draw a vertical line down from the middle star of the W through the next star into the glow of the Milky Way. The Double Cluster appears to the unaided eye as a brighter glow of the Milky Way. This is confirmed with binoculars. But in a small telescope it becomes two piles of sparkling diamonds. The clusters are much younger than the sun so their brightest stars are blue-white to our eyes. The average distance of the two from earth is 7,200 light years and the are 1200 light years from each other.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Double Cluster as it would be seen in a small telescope.
Chart for finding the Double cluster in October. Created using Stellarium.
10/12/2012 – Ephemeris – The constellation of Andromeda and its great galaxy
Ephemeris for Friday, October 12th. The sun will rise at 7:54. It’ll be up for 11 hours and 7 minutes, setting at 7:02. The moon, 3 days before new, will rise at 5:42 tomorrow morning.
In the east at 9 this evening can be found a large square of stars, the Great Square of Pegasus the flying horse. The square is standing on one corner. What look like its hind legs stretching to the left from the left corner star is another constellation, Andromeda the chained maiden. She is seen in the sky as two diverging curved strings of stars that curve upward. She was rescued by the hero Perseus, a nearby constellation, riding his steed Pegasus. Andromeda’s claim to astronomical fame is the large galaxy seen with the unaided eye just above the upper line of stars, the Great Andromeda Galaxy, nearly 2 and a half million light years away. To the unaided eye the galaxy appears as a small smudge of light. In binoculars the galaxy is a delicate spindle of light.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Andromeda at 9 p.m. with the Great Andromeda Galaxy. Created using Stellarium.
The Great Andromeda Galaxy (M31). Image taken by Scott Anttila.
10/10/2012 – Ephemeris – Where are the bright planets this week?
Oct 10. This is Bob Moler with Ephemeris for Wednesday, October 10th. The sun will rise at 7:52. It’ll be up for 11 hours and 13 minutes, setting at 7:05. The moon, 2 days past last quarter, will rise at 3:22 tomorrow morning.
Let’s see how many bright planets we can find this week. Mars and Saturn now set too close to the sun to be easily seen in the evening sky. Both are in the west southwestern sky and very low in twilight. Saturn will set at 7:45 p.m., while Mars will set at 8:56. The planetary action moves to later in the evening and the morning. Jupiter, will rise at 9:45 p.m. in the east northeast. It is located in the constellation of Taurus. The last bright planet of the night is the morning star Venus which will rise at 4:28 a.m. also in the east northeast. Venus is now in Leo outshining the star Regulus next to it. The planets Venus and Jupiter and the winter constellations are a great sight for early risers. You can enjoy for a few more weeks without danger of frost bite.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars is approaching Antares at 8 p.m. on October 10, 2012. Created using Stellarium.
Morning Sky at 6 a.m. with Jupiter and Venus on October 11, 2012. Created using Stellarium.
Note that the moon is really a thin crescent and is over blown at this scale.
10/09/2012 – Ephemeris – Capricornus the sea-goat
Ephemeris for Tuesday, October 9th. The sun will rise at 7:50. It’ll be up for 11 hours and 16 minutes, setting at 7:07. The moon, 1 day past last quarter, will rise at 2:16 tomorrow morning.
The sky around 9 p.m. when it gets dark is that of summer stars overhead and to the west while the stars of autumn approach from the east. The southern terminus of the Milky Way will reach the horizon in the southwest. The teapot shaped constellation of Sagittarius is tipped as if pouring its contents on the southwestern horizon. To the south is found the next constellation of the Zodiac Capricornus the sea goat. Capricornus doesn’t have as bright a stars as Sagittarius. It looks like the stars trace a sagging triangle. Capricornus used to be the southernmost constellation of the Zodiac in ancient times, but precession, the slow wobbling of the earth’s axis, has shifted Sagittarius to that position now.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Capricornus the way I see it. Created using Cartes duCiel.
10/08/2012 – Ephemeris – The Draconid Meteor Shower
Ephemeris for Columbus Day, Monday, October 8th. The sun will rise at 7:49. It’ll be up for 11 hours and 19 minutes, setting at 7:09. The moon, at last quarter today, will rise at 1:13 tomorrow morning.
The peak of the Draconid meteor shower is about now, (6-7 a.m. when the program airs) as the radiant point for these meteors is low in the north. They will be visible for the next few days seeming to radiate from the head of the constellation Draco, near the star Vega high in the west. These meteors are best about every 7 years, the last was last year. So maybe we may see 15 to 20 of these meteors per hour this time. These meteors are debris shed by Comet Giacobini-Zinner a short period comet of only 6.6 years. These meteors are very slow moving, about a third the velocity of the Perseid meteors of August. Meteors are the light given off by tiny bits of material sand grain to pea size as a rule as they burn up by friction due to their great speed.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Draconid Meteor Shower Radiant
