04/06/11 – Ephemeris – The bright planets for this week
Wednesday, April 6th. The sun will rise at 7:14. It’ll be up for 13 hours and 1 minute, setting at 8:15. The moon, 3 days past new, will set at 11:46 this evening.
It’s Wednesday and time again to take a look at the whereabouts of the bright planets for this week. Jupiter is in conjunction with the sun today and will enter the morning sky. It’ll be more than a month before it’s easily spotted in the morning twilight. The ringed planet Saturn is rising before sunset and will be visible low in the southeast as it gets dark. It will cross the meridian due south at 1:37 a.m. and will set at 7:27 a.m. In telescopes Saturn shows its rings which are a year and a half along their seven and a half year opening along with at least one satellite, the large moon Titan. Venus is brilliant in the morning sky and will rise at 6:09 a.m. in the east southeast. It is really a beautiful sight in the morning twilight, though disappointingly small in a telescope.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
04/04/11 – Ephemeris – Saturn at opposition
Apr 4. This is Bob Moler with Ephemeris for Monday, April 4th. The sun will rise at 7:18. It’ll be up for 12 hours and 54 minutes, setting at 8:13. The moon, 1 day past new, will set at 9:43 this evening. | Last night Saturn passed opposition from the sun, that is Saturn was opposite the sun in the sky. That means the earth is nearly directly between them. Also Saturn is at its closest. That’s not as big a deal as with Mars. Saturn, nearly 10 times earth’s distance from the sun, will vary its distance from the earth by plus or minus 10 percent. Not a huge amount. With Jupiter its plus or minus 25 percent. With Mars it’s plus or minus 75 percent. That plus Mars’ eccentric orbit means we only have rare close approaches, every 15 or 17 years. So Saturn appears about the same size no matter were in its orbit or our orbit we see it. We’ll have nearly six months of Saturn viewing in the evening. And Saturn’s the one planet you have got to see in a telescope.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn as seen in April 2011. Created by Celestia.
The above image isn’t a photograph, but was created using Celestia. This is roughly the view of Saturn we see now. Celestia is available free. See the link to the right.
04/01/11 – Ephemeris – Astronomical events in the Grand Traverse area this weekend
April Fools Day, Friday, April 1st. The sun will rise at 7:23. It’ll be up for 12 hours and 45 minutes, setting at 8:09. The moon, 2 days before new, will rise at 6:34 tomorrow morning.
This evening Northwestern Michigan College’s own professor Jerry Dobek will present a talk about the book to be released at the end of this month at this evening’s meeting of the Grand Traverse Astronomical Society starting at 8 p.m. at the college’s Rogers Observatory.. Jerry is republishing A Photographic Atlas of Selected Regions of the Milky Way by E. E. Barnard from the best plates of the 1927 edition with additions and corrections to the original tables. Tomorrow evening starting at 9 p.m. the Society along with the NMC Astronomy Association will host a public viewing night at the observatory. This will be our last chance, if it’s clear to view the setting winter celestial wonders and we’ll get a preview of the rising ones of spring.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
03/31/11 – Ephemeris – The Big Dipper as seen by other cultures
Thursday, March 31st. The sun will rise at 7:25. It’ll be up for 12 hours and 42 minutes, setting at 8:08. The moon, 3 days before new, will rise at 6:13 tomorrow morning.
The Big Dipper is in the northeast nearing overhead at 10 in the evening, it’s seven stars shining brightly. The Big Dipper is not an actual constellation, recognized internationally. It’s part, the hind part, of Ursa Major, the great bear. The Big Dipper is an asterism or informal constellation. It is a distinctly North American constellation. For fugitive slaves, fleeing the southern states in the days before the Civil War, the Drinking Gourd, as they called it, showed the direction to freedom. In England the dipper stars become the Plough, or Charles’ Wain (Charlemagne’s Wagon), In France, known for culinary delights it was the saucepan, or the cleaver. So, other cultures saw what they wanted to see in these seven bright stars.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Big Dipper as seen from other cultures - animation
Big Dipper/Sauce Pan, Plough (plow), Charles’ Wain (Charlemagne’s wagon), and the Cleaver.
03/30/11 – Ephemeris – The bright planets this week
Wednesday, March 30th. The sun will rise at 7:27. It’ll be up for 12 hours and 39 minutes, setting at 8:07. The moon, half way from last quarter to new, will rise at 5:51 tomorrow morning.
It’s Wednesday and time again to take a look at the whereabouts of the bright planets for this week. Mercury is fading fast as its phase becomes a thinner crescent. It’s be a real challenge to spot low in the west after sunset. It would take a pair of binoculars or telescope to have any hope of spotting it. It will set at 9:29 p.m. Jupiter is now too close to the direction of the sun to spot after sunset since it will set at 8:26. The ringed planet Saturn will rise at 8:17 p.m. in the east southeast and will move due south at 2:06 a.m. In telescopes Saturn shows its rings which are a year and a half along their seven and a half year opening. Venus is brilliant in the morning sky and will rise at 6:16 a.m. in the east southeast. It is really a beautiful sight in the morning twilight.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
03/29/11 – Ephemeris – Ursa Major
Tuesday, March 29th. The sun will rise at 7:29. It’ll be up for 12 hours and 36 minutes, setting at 8:05. The moon, 3 days past last quarter, will rise at 5:29 tomorrow morning.
The Big Dipper is now nearly overhead in the northeast at 10 p.m. The seven bright stars are second to Orion in the southwest as the seven brightest stars in a constellation. If you looked up a list of constellations, you’d find that the Big Dipper isn’t there. Ursa Major or the Great Bear is the constellation of which the Big Dipper is a part. The seven bright stars of the dipper is the rump and long tail of this constellation. The rest of the bear, including his head and legs are delineated by dimmer stars. An anatomical problem is its long tail, which was drawn in by the ancients of the old world. The American Indians, also saw a bear in the stars here, but the handle of the dipper became three hunters following the bear.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
My rather crude drawing of Ursa Major, the Great Bear
03/28/11 – Ephemeris – The bright star Regulus
Monday, March 28th. The sun will rise at 7:31. It’ll be up for 12 hours and 33 minutes, setting at 8:04. The moon, 2 days past last quarter, will rise at 5:05 tomorrow morning.
Regulus is the brightest star in the constellation of Leo the lion. Leo is high in the southeast at 10 p.m. It can be found by imagining a leak in the bottom of the Big Dipper. The water would fall on Leo’s back. Regulus is the star lower right corner of the constellation. Alluding to the lion’s status in the animal kingdom, Regulus is the little king star. It is dead last in order of brightness of the 21 first magnitude stars, 1/13th the brightness of Sirius the brightest star low in the southwest at the same time. To the Babylonians it was the king, the 15th of their constellations that marked the passage of the sun. Regulus is about 77 light years away, and 150 times the brightness of the sun. [It is a rapidly spinning ellipsoid 3 and a half times the sun’s mass.]
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location. Text in brackets was omitted from the recorded program due to time constraints.
Addendum
Leo in the southeast. Created using Stellarium.
03/25/11 – Ephemeris – The stars Castor and Pollux
Friday, March 25th. The sun will rise at 7:36. It’ll be up for 12 hours and 24 minutes, setting at 8:00. The moon, 1 day before last quarter, will rise at 3:20 tomorrow morning
Castor and Pollux are the two brightest stars in the constellation Gemini, at the heads of their namesakes. They are high in the south at 10 p.m. Castor, the horseman is on top. It is actually 6 stars orbiting about a common center of gravity in pairs. The two brightest unresolved pairs, named Castor A and Castor B are discernible in telescopes. They all lie 45 light years away. Pollux the pugilist is a single star, slightly brighter than Castor, and somewhat closer to us at 33.7 light years. In his 1603 atlas of the heavens Johannes Bayer gave Castor the alpha designation to Pollux’s beta, even though Pollux is slightly brighter. I once took a photograph of Pollux during the daytime under special circumstances: it happened to be near the totally eclipsed sun.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Gemini with the stars Castor and Pollux. Created using Stellarium.
Click to enlarge.
03/24/11 – Ephemeris – The constellation Leo
Thursday, March 24th. The sun will rise at 7:38. It’ll be up for 12 hours and 20 minutes, setting at 7:59. The moon, 2 days before last quarter, will rise at 2:29 tomorrow morning
Besides the advancing sunset times and warming temperatures, there’s another sign that spring is here. That’s the appearance of the constellation Leo the lion high in the southeast in the evening. The front of this beast is a backward question mark of stars with the bright star Regulus as the dot at the bottom. That’s his head, mane and chest. His haunches are a triangle of stars to the left, ending with the bright star Denebola. A way to find Leo is to remember that cat’s aren’t supposed to like water. Find the Big Dipper high in the northeast and imagine drilling a hole in the bottom of the bowl. The water will fall on Leo’s back. Also you’ll notice the stars of spring to the east are more sparse than those of winter to the west.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
This is Tuesday’s image, showing how to locate Leo.
The Big Dipper points to other stars and constellations. Created using my own LookingUp program.
03/23/11 – Ephemeris – The bright planets this week
Wednesday, March 23rd. The sun will rise at 7:40. It’ll be up for 12 hours and 17 minutes, setting at 7:58. The moon, 3 days before last quarter, will rise at 1:28 tomorrow morning.
It’s Wednesday and time again to take a look at the whereabouts of the bright planets for this week. We are losing Jupiter low in the twilight It will set at 8:48 p.m. Now Mercury is actually easier to spot. Higher than Jupiter, it will be visible in twilight and will set at 9:39. My usual rule of thumb about spotting Mercury is that it will be easiest to spot about 45 minutes after sunset, which will be about 8:40 p.m.. The ringed planet Saturn will rise at 8:47 p.m. in the east southeast and will move due south at 2:36 a.m. In telescopes Saturn shows its rings which are a year and a half along their seven and a half year opening. Venus is brilliant in the morning sky and will rise at 6:22 a.m. in the east southeast. It is really a beautiful sight in the morning twilight.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
