Archive
03/29/2012 – Ephemeris – The moon tonight
Ephemeris for Thursday, March 29th. The sun will rise at 7:28. It’ll be up for 12 hours and 38 minutes, setting at 8:06. The moon, 1 day before first quarter, will set at 2:55 tomorrow morning.
Tonight’s moon will be nearly half full. The gray patches on the moon are from the upper right the sea of Crises, Below it is the sea of fertility, centered on the moon’s equator is the sea of Tranquility. Above that is the scallop shaped sea of Serenity. One of the interesting craters in viwe for a telescope now is the ruined crater Julius Caesar. It’s on the edge of Tranquility near Serenity. This is an ancient crater whose crater walls were breached by the impact that created the sea of Tranquility, so it kind of looks like the letter C. So how did this crater become named for a Roman Emperor? My only guess is that it was for his calendar reform giving us the 365 day year with a leap year every 4th. This is also a good time to check out the rest of the moon.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The moon at 10 p.m. 3/29/2012. Created using Virtual Moon Atlas.
03/28/2012 – Ephemeris – Where are the bright planets this week?
Ephemeris for Wednesday, March 28th. The sun will rise at 7:29. It’ll be up for 12 hours and 35 minutes, setting at 8:05. The moon, 2 days before first quarter, will set at 2:10 tomorrow morning.
Let’s see what’s happening with the bright planets for this week. Venus and Jupiter are separating in the western sky after sunset. Jupiter is below Venus, the brighter planet. Jupiter will set at 11:01 p.m. followed by Venus at 12:20 a.m. Mars is up in the southeast in the evening with its unmistakable bright reddish color. It’s in the constellation Leo the lion now. It is 68.3 million miles and moving away. Mars will pass due south at 11:43 p.m. and will be setting in the west at 6:37 a.m. Saturn will rise at 9:31 p.m. just to the left of the bright star Spica in the east southeast. It will pass due south at 3:01 We have 4 bright planets visible in the evening.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The stars and planets at 10:30 p.m. on 3/28/2012. Created using Stellarium,
03/27/2012 – Ephemeris – Supernova near the direction of Mars
Ephemeris for Tuesday, March 27th. The sun will rise at 7:31. It’ll be up for 12 hours and 32 minutes, setting at 8:04. The moon, 3 days before first quarter, will set at 1:19 tomorrow morning.
Last week a supernova was spotted in nearby galaxy M95, which happens to be close to the direction where Mars is right now. It takes a telescope of about 6 inch diameter to spot it. If you’d like to spot it, Google “M95 supernova” for more information on its exact location. Since discovery, astronomers have found the progenitor star on an old image of the galaxy taken by the Hubble Space Telescope. The star that blew itself up appears to have been 8 times the mass of the sun as determined by its color and brightness. We don’t have to worry about the sun doing the same thing, it’s simply not massive enough. It’s nice to live orbiting around a boring star of low mass. Our sun’s wildness is seen in the sunspot cycle.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Finder Charts
Mars' motion from March 26th to April 2nd 2012. Created using Cartes du Ciel.
Closeup Mars and M95 for the dates March 27th to April 2nd 2012. Created using Cartes du Ciel.
M95 and neighboring galaxies. The supernova will appear below M95. The faintest stars here are 10th magnitude. The supernova is about 12th. Created using Cartes du Ciel.
Google “M95 supernova” in Google images for what the supernova and galaxy look like.
03/23/2012 – Ephemeris – The moon will pass Jupiter Sunday Night
Ephemeris for Friday, March 23rd. The sun will rise at 7:39. It’ll be up for 12 hours and 20 minutes, setting at 7:59. The moon, 1 day past new, will set at 9:27 this evening.
The thin crescent moon is moving away from the setting sun in the west. By Sunday evening it will be to the upper right of Jupiter. In the moon’s monthly journey around the sun it passes each of the planets in turn, because the moon, earth and most of the planets lie very close to the same plane. The sun and the solar system condensed out of a cloud which spun in a flat disk. The sun had the most mass and began to glow as a star. The other material accreted into protoplanets, then into larger planets. Spiral galaxies also have this flattened appearance. It is the reason the Kepler satellite can pick up so many exoplanets around other stars. Of the tiny fraction of stellar planetary planes tilted our way, there can be multiple planets found in each.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Jupiter and Moon march 25, 2012 at 10:15 p.m.. Created using Stellarium.
03/22/2012 – Ephemeris – Leo the lion and Mars
Ephemeris for Thursday, March 22nd. The sun will rise at 7:41. It’ll be up for 12 hours and 17 minutes, setting at 7:58. The moon is new today, and won’t be visible.
One of the great constellations of spring is up in the southeastern sky. This month Leo can be found by the bright planet Mars which adds a bright red star to the constellation. The head and mane of this beast is a backward question mark. It’s also known as the sickle. The bright star Regulus is at the bottom of this figure. It is now dimmer than Mars. To the east or left of Regulus and Mars is the triangle of stars that is his rump. The lion is special for several ancient cultures. Another way to find him when Mars isn’t around is to use the Bug Dipper, now soaring high in the northeast. Drill a hole in the bottom of the bowl of the dipper and imagine the water flowing out to the south and it will fall on the back of Leo the lion.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mars and the constellation of Leo the lion March 22, 2012. Created using Stellarium.
03/21/2012 – Ephemeris – Where are the bright planets this week?
Ephemeris for Wednesday, March 21st. The sun will rise at 7:42. It’ll be up for 12 hours and 13 minutes, setting at 7:56. The moon, 1 day before new, will rise at 7:18 tomorrow morning.
Let’s see what’s happening with the bright planets for this week. Mercury will pass between the earth and the sun, and will enter the morning sky this afternoon, so is invisible. Venus and Jupiter are separating in the western sky after sunset. Jupiter is below of Venus, the brighter planet. Jupiter will set at 11:20 p.m. followed by Venus at 12:05 a.m. Mars is up in the southeast in the evening with its unmistakable bright reddish color. It’s in the constellation Leo the lion now. It is 65.2 million miles and moving away. Mars will pass due south at 12:23 a.m. and will be setting in the west at 7:15 a.m. Saturn will rise at 10:01 p.m. just to the left of the bright star Spica in the east southeast. We have 4 bright planets visible in the evening.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The planets visible at 10:30 p.m. March 21, 2012. Created using Stellarium.
Scott Anttila was photographing the red planet instead of drinking green beer on Srt. Patrick’s day night. Here is the result.
Mars on March 17, 2012 at 10:15 p.m. edt. Photo by Scott Anttila.
This I generally consider the bland side of Mars. However the white blotch near the center appears to be clouds over the largest mountain in the solar system Olympus Mons. I’m willing to bet the three white blotches to the right of it are clouds over the three Tharsis volcanoes, from top to bottom: Ascraeus Mons, Pavonis Mons and Arsia Mons.
03/20/2012 – Ephemeris – First day of spring
Ephemeris for Tuesday, March 20th. The sun will rise at 7:44. It’ll be up for 12 hours and 10 minutes, setting at 7:55. The moon, 2 days before new, will rise at 6:54 tomorrow morning.
At 1:14 this morning the season of spring started. The sun crossed the celestial equator heading northward. On the day of the equinox, either today’s vernal equinox or September’s autumnal equinox the sun rises due east and sets due west. From today until that September date the sun will rise and set north of those points. The sun will also rise higher in the sky until the summer solstice. The combination of longer daylight hours and it rising higher in the sky will mean more solar heat falling on the northern hemisphere of the earth and less falling on the southern. This will give us spring and summer, and the southern hemisphere autumn and winter. After a really screwy winter I wonder what spring and summer will bring.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
03/19/2012 – Ephemeris – The last day of winter
Ephemeris for Monday, March 19th. The sun will rise at 7:46. It’ll be up for 12 hours and 7 minutes, setting at 7:54. The moon, 3 days before new, will rise at 6:30 tomorrow morning.
This is the last full day of winter. And a strange winter it is, ending today with record high temperatures. Tomorrow at 1:14 a.m. spring will officially start. At that time the earth will move to a point in its orbit where the sun will appear to cross the equator in the sky, and will appear to pass directly overhead if you lived on the equator. The event of the crossing and the point on the celestial sphere that the sun crosses the equator is called the vernal equinox. It’s the Greenwich of the heavens. All measurements east and west in the sky are measured from this point. And its position in relation to the prime meridian on the earth at Greenwich, near London is the fundamental measure of the earth’s rotational position.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The sun at the vernal equinox. Diagram by Wikipedia contributor Tauʻolunga GNU Free Document License
Click on image to enlarge.
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.
