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04/03/2012 – Ephemeris – Venus passes the Pleiades part 2.
Ephemeris for Tuesday, April 3rd. The sun will rise at 7:18. It’ll be up for 12 hours and 54 minutes, setting at 8:13. The moon, 3 days before full, will set at 5:43 tomorrow morning.
The brilliant planet Venus is passing by the Pleiades star cluster. It will be a great sight in the west in the evening. Binoculars will help in picking out the Pleiads, as the individual stars of the Pleiades are called. The celestial sphere is the ultimate reference frame for objects in the heavens. It used to be the stars, but the stars move, the sun moves and the earth moves. Now the standard for an unmoving frame of reference is distance quasars, the nearly stellar in size active cores of distant galaxies. While they’re moving too, they are so far away we cannot detect any motion on the celestial sphere. Our earth centered frame of reference rotates within that at once in 26 thousand years as the earth’s axis precesses due to the gravitational pull of the moon.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus passing the Pleiades April 2 - 4, 2012. Created using Cartes du Ciel.
Click here for a Space.com write up on how quasars are being used as a reference for the GPS system.
04/02/2012 – Ephemeris – Venus will pass the Pleiades tonight
Ephemeris for Monday, April 2nd. The sun will rise at 7:20. It’ll be up for 12 hours and 51 minutes, setting at 8:11. The moon, 3 days past first quarter, will set at 5:14 tomorrow morning.
This evening Venus starts a pass by the Pleiades star cluster. The Pleiades is also known as the Seven Sisters and soon it will disappear in the twilight glow. The next time it will be seen in the evening is in next October. Venus will head back toward the sun, which it will pass directly in front of on June 5th. The sun will pass the Pleiades in mid May, so Venus will never quite make it back to the Pleiades this go around anyway. Though Venus is beginning to head back to the sun, it is still moving eastward against the stars, though a little slower than the sun. Right now Venus is mostly heading toward us. Around the 16th of May Venus will finally stop its eastward motion with respect with the stars and will head westward.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus passing the Pleiades April 2 - 4, 2012. Created using Cartes du Ciel.
In the real sky Venus is a heck of a lot brighter than you see here. And with binoculars, you’ll see a lot more stars in the Pleiades.
03/26/2012 – Ephemeris – The moon will pass Venus today
Ephemeris for Monday, March 26th. The sun will rise at 7:33. It’ll be up for 12 hours and 29 minutes, setting at 8:03. The moon, half way from new to first quarter, will set at 12:25 tomorrow morning.
Yesterday the moon moved past Jupiter in the sky. Today the moon will pass Venus, the brightest planet. Check them out in the west southwest in the evening after sunset. Venus is going to be at greatest elongation from the sun tomorrow. Venus is at an angle of 46 degrees from the sun, and it will soon diminish. As it does, this is the best time to view Venus in a telescope. 400 years ago Galileo observed Venus with his small telescope and observed that Venus had phases like the moon, and its size changed proving that Venus orbited the sun and not the earth. You can repeat his observations this spring. Venus now appears about half illuminated by the sun, like the quarter moon. Its phase will thin and it will grow in size.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon passing Venus with Jupiter below. Created using Stellarium.
03/16/2012 – Ephemeris – Jupiter and Venus: Where do they go from here?
Ephemeris for Friday, March 16th. The sun will rise at 7:52. It’ll be up for 11 hours and 58 minutes, setting at 7:50. The moon, 2 days past last quarter, will rise at 5:02 tomorrow morning.
Now that the conjunction of Jupiter and Venus us over, what happens next? Well, Jupiter will continue to head westward toward the sun, and soon will be caught up into twilight. Its and principally the earths motion will move it behind the sun on May 13th. Venus still has 11 days before it reaches its greatest elongation from the sun, then it too will appear to head back toward the sun. It will actual cross in front of the sun on the evening of June 5th, where we will see the first part of the extremely rare transit of Venus. These transits occur in pairs 8 years apart separated by more than a century. The last was in 2004, the next will occur in 2117. Observations of these in the 18th century helped determine the distance to the sun.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The planets at 11 p.m. March 14, 2012. Created using Stellarium.
The last step of the animation shows Jupiter and Venus tonight.
03/15/2012 – Ephemeris – Astronomical Conjunction of Jupiter and Venus
Ephemeris for Thursday, March 15th. The sun will rise at 7:53. It’ll be up for 11 hours and 55 minutes, setting at 7:49. The moon, 1 day past last quarter, will rise at 4:22 tomorrow morning.
This morning is the actual conjunction of Jupiter and Venus according to astronomers. They may have looked closest yesterday or the day before, but this morning is the time they appear at the same right ascension. Right ascension is the celestial equivalent to longitude on the earth. Meaning that Venus would be directly north of Jupiter. The terms celestial longitude and latitude have already been taken, and are actually oriented to the plane of the earth’s orbit, rather to the earth’s axis and equator. First year astronomy students accuse instructors of using such terms just to confuse them. Astronomers call the angle for the tilt of the earth’s axis the obliquity of the ecliptic. How’s that for a tongue twister.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Venus at nightly intervals from March 12 to 16, 2012. Created using Stellarium.
The 4th step, the one before the last is where Jupiter and Venus are tonight.
03/14/2012 – Ephemeris – Where are the bright planets this week?
Wednesday, March 14th. The sun will rise at 7:55. It’ll be up for 11 hours and 52 minutes, setting at 7:47. The moon, at last quarter today, will rise at 3:35 tomorrow morning.
Let’s see what’s happening with the bright planets for this week. Mercury will make a brief appearance in the west after sunset. It will set at 8:54. Venus and Jupiter are brilliant in the western sky after sunset. Jupiter will be just below left of Venus, the brighter planet. Jupiter will set first at 11:40 p.m. followed by Venus at 11:53. Mars is up in the east in the evening with its unmistakable bright reddish color. It’s in the constellation Leo the lion now. It is 63.5 million miles and moving away. Mars will pass due south at 1:04 a.m. and will be setting in the west near sunrise. Saturn will rise at 10:31 p.m. just to the left of the bright star Spica in the east southeast.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The planets at 11 p.m. March 14, 2012. Created using Stellarium.
03/13/2012 – Ephemeris – Jupiter now to the lower left of Venus
Ephemeris for Tuesday, March 13th. The sun will rise at 7:57. It’ll be up for 11 hours and 49 minutes, setting at 7:46. The moon, 1 day before last quarter, will rise at 2:38 tomorrow morning.
Tonight the planet Jupiter will begin to tuck under Venus coming from the left as they appear together in the west after sunset. Venus and Jupiter are the two brightest planets seen in the sky. Venus is the brightest for two reasons. Number one, its close to us. It is actually the closest planet to the earth. When it passes between us and the sun June 5th, it will be only 26.8 million miles away. That’s a bit farther than normal, since the earth will be a month away from its farthest point from the sun. Also Venus’ sulfuric acid cloud tops reflect most of the light it receives from the sun. Jupiter is bright due to its great size with a surface area over 120 times that of the earth. Still sunlight is diluted to one twenty fifth that of earth.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Venus at nightly intervals from March 12 to 16, 2012. Created using Stellarium.
Tonight’s position of the planets is the second frame of the animation.
03/12/2012 – Ephemeris – Jupiter is level with Venus, also possible northern lights tonight
Ephemeris for Monday, March 12th. The sun will rise at 7:59. It’ll be up for 11 hours and 45 minutes, setting at 7:45. The moon, 2 days before last quarter, will rise at 1:33 tomorrow morning.
In the western evening sky, Jupiter and Venus are making a pass at each other. They shouldn’t, in the modern sense since Venus or Aphrodite of the Greeks was the daughter of Jupiter or Zeus. .Over this week we’ll watch as Jupiter slips below Venus to lead Venus in setting. Tonight Jupiter is level with and left of Venus. Venus will always be the brighter of the two. We also have an aurora watch for this evening. The sun has been active this weekend with a series of flares emanating from the largest sunspot group now visible called active region 1429. This group is rotating off so it’s flares soon won’t affect the earth. Check spaceweather.com for the latest. And check bobmoler.wordpress.com for an animation of the planet conjunction.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Venus at nightly intervals from March 12 to 16, 2012. Created using Stellarium.
The first frame of the animation is for tonight.
02/24/2012 – Ephemeris – The moon will pass Venus and Jupiter this weekend
Friday, February 24th. The sun will rise at 7:29. It’ll be up for 10 hours and 53 minutes, setting at 6:22. The moon, 3 days past new, will set at 9:36 this evening.
This weekend we will be able to spot appearances of the moon passing two planets. Tomorrow night Venus will appear below the moon. It should be a spectacular sight with Jupiter nearby to the upper left. Then Sunday night the moon will have moved near Jupiter. This time Jupiter will appear to the left of the moon, their closest apparent approach being after they set Monday morning. Even though the moon will leave these planets, keep watching them. As Venus slowly approaches Jupiter. They will be their closest, called a conjunction on the Ides of March. That’s March 15th using our calendar. These two planet will still be with us for the next few months, with Mars and Saturn appearing later in the evening now.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The moon will pass above Venus at 7 p.m. Saturday February 25, 2012. Created using Stellarium.
The moon will pass Jupiter, seen at 10 p.m. February 26, 2012. Created using Stellarium.
02/08/2011 – Ephemeris – Where are the bright planets?
Ephemeris for Wednesday, February 8th. The sun will rise at 7:53. It’ll be up for 10 hours and 7 minutes, setting at 6:00. The moon, 1 day past full, will rise at 7:24 this evening.
Let’s see what’s happening with the bright planets for this week. Venus is brilliant in the southwestern sky after sunset and will set at 9:35 in the west. Jupiter the second brightest planet after Venus. It’s located high in the southwest as it gets dark and is seen against the stars of the constellation Aries. It will set at 12:25 a.m.. Mars is the up and coming planet. It will rise at 8:31 p.m in the east and is below the hind end of the constellation Leo the lion. It is 69.2 million miles away and closing and is getting brighter. It’s now as bright as most first magnitude stars. Mars will pass due south at 3:01 a.m. Saturn will rise at 11:54 p.m. just to the left of the bright star Spica in the east southeast.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus by Scott Anttila. Taken Monday evening February 6, 2012
Jupiter by Scott Anttila. Taken Monday evening February 6, 2012
Bob Moler's Ephemeris Blog 