Archive
05/29/2012 – Ephemeris – The moon tonight
Ephemeris for Tuesday, May 29th. Today the sun will be up for 15 hours and 16 minutes, setting at 9:18. The moon, 1 day past first quarter, will set at 2:38 tomorrow morning. Tomorrow the sun will rise at 6:01.
The moon tonight is a wonderful sight for binoculars or a small telescope. There are some very nice craters now revealed near the terminator, the line between day and night on the moon. The terminator in the two weeks between new and full is the sunrise line on the moon. From the top or north on the moon is the flat floored crater Plato Then about midway down the moon and right on the terminator is the beautiful crater Copernicus. Then to the south end of the moon is the bright and crisp crater Tycho. Its splash marks called rays will be better revealed at full moon. At the bottom of the moon, just coming into light is the huge crater Clavius. A telescope will reveal smaller craters within.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The moon on 5/29/2012 showing large craters on the terminator. Created using Virtual Moon Atlas.
05/28/2012 – Ephemeris – Memorials in the solar system
Ephemeris for Memorial Day, Monday, May 28th. Today the sun will be up for 15 hours and 14 minutes, setting at 9:17. The moon, at first quarter today, will set at 2:10 tomorrow morning. Tomorrow the sun will rise at 6:01.
Memorial day is a day of remembrance for those who paid the ultimate price for our freedom. When astronomers name craters or other features on planets or moons, they are names of those who have gone before. For instance craters near the moon’s north and south poles are named for explorers of the corresponding earthly pole. The Challenger astronauts have craters named for them in the moon system of Uranus, from discovery pictures relayed to the earth by Voyager 2 a few days before the Challenger accident. The Mars Rover Spirit is itself a silent sentinel in the Columbia Hills on Mars, its features named for the Columbia astronauts who died 11 months before Spirit landed.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
05/25/2012 – Ephemeris – Of conjunctions, superior and inferior
Ephemeris for Friday, May 25th. Today the sun will be up for 15 hours and 10 minutes, setting at 9:14. The moon, 3 days before first quarter, will set at 12:45 tomorrow morning. Tomorrow the sun will rise at 6:03.
The planet Mercury will pass the behind the sun this weekend, in what is called superior conjunction. It is called that because Mercury is beyond or superior to the sun. Venus and Mercury can have both superior and inferior conjunctions because they are inferior planets, not a statement of their quality, but simply because they reside in orbits between the earth and the sun. A conjunction occurs when two solar system bodies pass each other from our point of view. Anyway Mercury will slowly move into our evening sky and by July first might be glimpsed in evening twilight. Mercury can be seen near its greatest elongations or separations from the sun on spring evenings and autumn mornings. July will push it a bit.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
05/24/2012 – Ephemeris – Phases and shadows on the moon
Ephemeris for Thursday, May 24th. Today the sun will be up for 15 hours and 8 minutes, setting at 9:13. The moon, half way from new to first quarter, will set at 12:11 tomorrow morning. Tomorrow the sun will rise at 6:04.
The fat crescent moon tonight is like the crescent Venus, with the sun shining on mostly the far side. I notice that some folks think that the earth is casting its shadow on the moon to cause the crescent. That isn’t correct. The earth does cast its shadow on the moon sometimes, but only at full moon, but only about one in 6 full moons, and we usually don’t see many of these. The phases of the moon are simply the light and shadow of a ball in the sunlight. In fact, if before sunset you can see the moon, and you are in sunlight also. Hold the ball up next to the moon. You will see that the ball will have the same phase as the moon. This is because the moon is close to the earth.
05/23/2012 – Ephemeris – Where are the bright planets this week?
Ephemeris for Wednesday, May 23rd. Today the sun will be up for 15 hours and 6 minutes, setting at 9:12. The moon, 3 days past new, will set at 11:33 this evening. Tomorrow the sun will rise at 6:05.
Let’s see what’s happening with the bright planets for this week. Venus is in the west as it gets dark. Enjoy it now, because it will be gone in less than 2 weeks. Venus will set at 11:07 p.m. in the west northwest. That’s 33 minutes earlier than last week, so it appears to be drawing closer to the sun. Venus is 29.5 million miles away and closing slowly. It is a beautiful brilliant growing crescent in telescopes. Mars is high in the south southwest in the evening in the constellation of Leo with its unmistakable bright reddish color. It’s beginning to resume its eastward motion toward Virgo. Mars will be setting in the west at 3:05 a.m. Saturn will be in the southeast moving above above the bright star Spica.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The evening sky with the remaining bright planets at 10 p.m. tonight. Created using Stellarium.
05/22/2012 – Ephemeris – The moon appears near Venus tonight
Ephemeris for Tuesday, May 22nd. Today the sun will be up for 15 hours and 4 minutes, setting at 9:11. The moon, 2 days past new, will set at 10:50 this evening. Tomorrow the sun will rise at 6:06.
Tonight the extremely thin crescent moon will appear below and left of the planet Venus. Venus itself is an extremely thin crescent, just two weeks from passing directly in front of the sun in a rare transit part of which will be visible from here. Venus is a crescent because we are looking mostly on its night side, with just a sliver of light on its sunlit edge. Even though Venus shows such a small sunlit sliver, it’s still very bright, since its nearness to us makes it appear larger in our sky. You can even see the crescent in binoculars. Venus is so bright because it’s close to us, just slightly smaller than the earth, but socked in by while sulfuric acid clouds that reflect most of the suns light covering a runaway green house effect beneath.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus with the moon on the evening of May 22, 2012. Created using Stellarium.
05/21/2012 – Ephemeris – What are the next solar eclipses to be visile from Northern Michigan?
Ephemeris for Monday, May 21st. Today the sun will be up for 15 hours and 2 minutes, setting at 9:10. The moon, 1 day past new, will set at 10:01 this evening. Tomorrow the sun will rise at 6:07.
With yesterday’s solar eclipse now history, when will we see the next one? The next solar eclipse visible from northern Michigan is another partial eclipse interrupted by sunset. That one’s on October 24, 2014, about two and a half years from now. It will be a partial eclipse for anyone able to see it. The central part of the moon’s shadow will miss earth to the north. In three years after that is a total eclipse whose path of totality crosses the United States from Oregon to South Carolina. That one is special to me. It will be the third saros periods of the first total eclipse I saw, back on July 20, 1963. Eclipses repeat in 18 years 10 or 11 1/3 days called a saros. The August 21, 2017 is that eclipse.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
05/18/2012 – Ephemeris – Eclipse viewing from the Sleeping Bear Dunes this Sunday
Ephemeris for Friday, May 18th. Today the sun will be up for 14 hours and 56 minutes, setting at 9:07. The moon, 2 days before new, will rise at 5:14 tomorrow morning. Tomorrow the sun will rise at 6:09.
For Sunday’s solar eclipse the Grand Traverse Astronomical Society will team up with the National Park Service for eclipse viewing at sunset on Pierce Stocking Scenic Drive at Sleeping Bear Dunes National Lakeshore. We’ll be stationed at either stop 3, the Dunes overlook, or stop 9 the Lake Michigan Overlook. There we will have telescopes for safe viewing of the eclipse, and the park service will have a number of eclipse viewer glasses that are safe to use. Our telescopes have special solar filters that fit in front of the telescope, and another special solar telescope to see the gasses above the bright ball of the sun. The eclipse will start at 8:19 p.m. And last until sunset at 9:10 p.m. If it’s overcast, the viewing will be canceled.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Views from the observation points. I took these shots May 12th.
View from the Lake Michigan Overlook. The trees won’t interfere.
Sunset from the dune Overlook. The dunes and scrub will cause the sunset at that point up to 5 minutes before the Lake Michigan Overlook.
05/17/2012 – Ephemeris – A safe way to view this Sunday’s solar eclipse
Ephemeris for Thursday, May 17th. Today the sun will be up for 14 hours and 54 minutes, setting at 9:06. The moon, 3 days before new, will rise at 4:44 tomorrow morning. Tomorrow the sun will rise at 6:10.
Lets talk about a safe viewing method for viewing the sun, for Sunday’s solar eclipse, which starts about 8:19 p.m. Never look directly at the sun, eclipse or no. Pinhole projection is a cool method to watch the eclipse without hurting your eyes. Get a cardboard box, the longer the better. On one narrow end poke a hole, no larger than an 8th of an inch in diameter. You can poke several holes an inch apart of varying sizes to get multiple images of the sun of different brightnesses and sharpness. On the inside of the other end paste a piece of white paper. Point the holey end at the sun and its image will be projected on the white sheet. Tomorrow I’ll tell you where to go to get the best view of the eclipse.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
There’s more information on my blog here.
Pinhole projection:
Pinhole Projection of the sun.
Note the brightness of the sun was augmented and moon shadow added to give an idea what the solar image would look like. The box is 39 inches long. it gives an image 1/3 of an inch in diameter.
05/16/2012 – Ephemeris – Where the bright planets this week?
Ephemeris for Wednesday, May 16th. Today the sun will be up for 14 hours and 52 minutes, setting at 9:05. The moon, half way from last quarter to new, will rise at 4:16 tomorrow morning. Tomorrow the sun will rise at 6:11.
Let’s see what’s happening with the bright planets for this week. Venus is in the west as it gets dark. Enjoy it now, because it will be gone in less than 3 weeks. Venus will set at 11:40 p.m. in the west northwest. That’s 29 minutes earlier than last week, so it’s drawing closer to the sun. Venus is 32.1 million miles away and closing. It is a beautiful brilliant growing crescent in telescopes. Mars is high in the south southwest in the evening in the constellation of Leo with its unmistakable bright reddish color. It’s up to 99 million miles from us and moving away. Mars will be setting in the west at 3:28 a.m. Saturn will be in the southeast just to the left of the bright star Spica this evening.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Planets move westward at 10:30 p.m. May 16, 2012. Created using Stellarium
