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07/04/2013 – Ephemeris – Patriotic Stars: Red, White and Blue
Ephemeris for Independence Day in the United States, Thursday, July 4th. Today the sun will be up for 15 hours and 27 minutes, setting at 9:30. The moon, half way from last quarter to new, will rise at 4:05 tomorrow morning. Tomorrow the sun will rise at 6:03.
Today is Independence Day so let’s look for some red, white, and blue stars. Red is easy, the red star Antares is seen in the south at 11 p.m. White is easy too, the official white calibration star Vega high in the east at 11 p.m. The blue star is really blue-white. The brightest of these out at 11 p.m. is Spica, low in the southwest to the right of the brighter Saturn. The color is best seen in binoculars. Star colors are quite subtle, and are an indicator of the temperature of their outer gaseous layers. The temperature of a stars outer layers, in order of their increasing temperatures are red, white and blue. Of these three the coolest on the outside, Antares is really the hottest inside, using helium as fuel.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Red Antares, white Vega and blue Spica. Patriotic Stars this evening. Created using Stellarium.
06/06/2013 – Ephemeris – Star colors
Ephemeris for Thursday, June 6th. Today the sun will be up for 15 hours and 26 minutes, setting at 9:24. The moon, 2 days before new, will rise at 5:22 tomorrow morning. Tomorrow the sun will rise at 5:57.
Star and planets colors are quite subtle. This is partly due to the fact that we are color blind at very low light levels. Only the brightest stars show color at all. Telescopes however aid our color perception because it makes the stars brighter. The planet Saturn, now in the south at night has a distinct yellowish hue, caused by the color of its atmosphere. The star Spica to its right is the bluest of the bright first magnitude stars, and shows as a bright arc light. Arcturus, above both Saturn and Spica has a yellow to orange hue. Antares low in the southeast has a definite reddish hue. In a telescope it also looks like a sparkler due to our turbulent atmosphere. Red stars are the coolest stars (temperature wise) while blue-white stars are the hottest.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Stellarium does a pretty good job of showing the subtle colors of stars, which is also reflected in the color of the star labels. Click on the image to enlarge.
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.
10/10/2012 – 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.
10/03/2012 – Ephemeris – Where are the bright planets this week?
Wednesday, October 3rd. The sun will rise at 7:43. It’ll be up for 11 hours and 35 minutes, setting at 7:18. The moon, 4 days past full, will rise at 8:59 this evening.
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 sets at 8:10 p.m., while Mars sets at 9:08. The planetary action moves to later in the evening and the morning. Jupiter, will rise at 10:09 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 4:13 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 them without danger of frost bite.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars and Antares low in the southwest at 8:20 p.m. on October 3, 2012. Created using Stellarium.
Mars is moving towards Antares, whose name means Rival of Mars. They have the same color. Mars, though will be dimmed and will pass north of the red giant star.
Morning skies including Jupiter and Venus at 6 a.m. on October 4, 2012. Created using Stellarium.
Click on the image to enlarge.
07/24/2012 – Ephemeris – The star Antares up close
The constellation Scorpius with Antares. Created using Stellarium.
Ephemeris for Tuesday, July 24th. The sun rises at 6:20. It’ll be up for 14 hours and 55 minutes, setting at 9:16. The moon, 2 days before first quarter, will set at 11:44 this evening.
Antares is a most interesting star. It’s low in the south and red in color. Its the heart of the Scorpius the scorpion. Its name means Rival of Mars with which it shares its color. Antares is a huge star, a red giant star. Its mass is 12 times the mass of the sun, but it’s bloated out to a diameter somewhat larger than the orbit of Mars, over 300 million miles. This what happens to a star that has exhausted hydrogen in its core and is now fusing helium to produce energy and even more massive elements. Its surface temperature is close to the temperature of the filament of an incandescent light bulb, about 2/3rds the temperature of the sun. Antares also has a dim companion star.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
07/17/2012 – Ephemeris – Scorpius and Orion
Ephemeris for Tuesday, July 17th. Today the sun will be up for 15 hours and 9 minutes, setting at 9:22. The moon, 2 days before new, will rise at 5:50 tomorrow morning. Tomorrow the sun will rise at 6:14.
Crawling just above the southern horizon at 11 p.m. is the zodiacal constellation of Scorpius the scorpion. His heart is the red giant star Antares. Its facing the west or right with a short arc of three stars as its head. His body and tail drop to the left and scrape the horizon before curving up to the critter’s poisonous stinger of two stars. One story of the scorpion concerns Orion the hunter the great winter constellation. In that story Orion was supposedly killed by the sting of a scorpion. Therefore Orion and Scorpius are never seen in the sky at the same time. That is certainly true around here and for the Greeks, whose legend it is. However if one travels far enough south that is no longer true.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The constellation Scorpius at 10:30 p.m. on July 17, 2012. Created using Stellarium.
07/10/2012 – Ephemeris – The constellation of Ophiuchus
Ephemeris for Tuesday, July 10th. Today the sun will be up for 15 hours and 20 minutes, setting at 9:27. The moon, at last quarter today, will rise at 12:50 tomorrow morning. Tomorrow the sun will rise at 6:08.
The red star Antares shines in the south at 11 p.m. In the area of sky above it lies a large constellation of faint stars called Ophiuchus, the serpent bearer. Ophiuchus represent the legendary physician Aesculapius. The constellation shape is like a large bell, which reminds me of the head, shoulders and arms of a fellow that’s holding the snake like a weight lifter struggling to pull up a heavy barbell. Serpens, the constellation of the serpent is in the sky in two sections. The front end lies to the right as Serpens Caput, and wends its way up towards Corona Borealis, the Northern Crown. Serpens Cauda, the tail rises to the left of Ophiuchus. It’s a rewarding sight, and not that hard to spot.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Ophiuchus and Serpens July 10, 2012 at 11 p.m.. Created using Stellarium.
06/14/2012 – Ephemeris – Flag Day: Red, White and Blue Stars
Ephemeris for Flag Day, Thursday, June 14th. Today the sun will be up for 15 hours and 32 minutes, setting at 9:29. The moon, 3 days past last quarter, will rise at 3:16 tomorrow morning. Tomorrow the sun will rise at 5:56.
Since it’s Flag Day, lets look for some red white and blue stars. Red is easy, I talked about it Tuesday, It is Antares now low in the southeast in the evening in the heart of the constellation of Scorpius the scorpion. For the white star there is no purer white star than Vega, spectral type A0 (A zero), the astronomers definition of white. It is located midway up the sky in the east. It is the 5th brightest night time star, and is seen off a small parallelogram of stars that make up the body of Lyra the harp. For the blue star, the best is Spica, below Saturn this year and in the south in the evening. It is the bluest of the 21 brightest first magnitude stars. Color in stars is often subtle, so try to see these colors.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Red (Antares), White (Vega) and Blue (Spica) stars of spring. Created using Stellarium.
06/12/2012 – Ephemeris – The bright star Antares
Ephemeris for Tuesday, June 12th. Today the sun will be up for 15 hours and 31 minutes, setting at 9:28. The moon, 1 day past last quarter, will rise at 2:20 tomorrow morning. Tomorrow the sun will rise at 5:56.
A rival to Mars is now low in southeast at 10:30. It is the red star Antares, whose names literally means “Rival of Mars”. This is from the Greek who’s god of war was Ares. Mars is in the southwest now and a bit brighter than Antares. When Mars catches up with Antares around October 20th this year, they will be nearly the same brightness, and one would be hard put to tell them apart. Antares is in the heart of Scorpius the scorpion which lies close to our southern horizon later in the evening, and is best seen next month at an earlier time. Antares is also a star that appears strange as its twinkling is very pronounced being always close to the horizon for us sputtering all the colors of the rainbow.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Antares and Mars at 11 p.m. on June 12, 2012. Created using Stellarium.
Bob Moler's Ephemeris Blog 