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07/12/2012 – Ephemeris – The constellation Lyra the harp
Thursday, July 12th. Today the sun will be up for 15 hours and 17 minutes, setting at 9:26. The moon, 2 days past last quarter, will rise at 1:50 tomorrow morning. Tomorrow the sun will rise at 6:10.
High in the east at 11 p.m. can be found a bright star called Vega just above a small, narrow, but very distinctive parallelogram of stars. They are the stars of the constellation Lyra the harp. Vega, the 5th brightest night time star, is one of the twenty one brightest stars, called first magnitude stars. The harp, according to Greek mythology, was invented by the god Hermes. The form of the harp in the sky, is as he had invented it: by stretching strings across a tortoise shell. Hermes gave it to his half-brother Apollo, who in turn gave it to the great musician Orpheus. In binoculars, near Vega, two stars appear together. They barely appear to the unaided eye as a single star, designated Epsilon Lyrae.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Summer Triangle and the constellation Lyra at 07-12-12 at 11 p.m. Created using Stellarium.
Closeup on Vega and Epsilon Lyrae. Created using Stellarium.
ε1 Lyrae is one of the stars of Epsilon Lyrae. The pair can be split better than this image with binoculars. Looking at the two with a good telescope and over 100 power can split each component into two more stars. We amateur astronomers call it the “Double-Double Star” Note too that Zeta (ζ) Lyrae is also a double star that can be split with a low power telescope.
07/11/2012 – Ephemeris – Where are the bright planets this week?
Ephemeris for Wednesday, July 11th. Today the sun will be up for 15 hours and 18 minutes, setting at 9:27. The moon, 1 day past last quarter, will rise at 1:18 tomorrow morning. Tomorrow the sun will rise at 6:09.
Let’s see what’s happening with the bright planets for this week. Mars, with its unmistakable bright reddish color, is in the west southwest in the evening in the constellation of Virgo the virgin. Mars will be setting in the west at 12:34 a.m. It is approaching Saturn and Spica just to its left. Saturn will be in the southwest above the bright star Spica now. It will set at 1:26 a.m. Jupiter, now a morning planet will rise at 3:08 a.m. in the east northeast. Venus, is now seen just below Jupiter after it rises at 3:45 a.m. Tomorrow morning, Venus will appear next to the bright star Aldebaran. The planets are striking in telescopes with Venus as a large thin crescent, and Jupiter with its cloud bands and satellites.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Looking westward at 10:30 p.m. on July 11, 2012. Created using Stellarium.
Click on image to enlarge.
Looking eastward at 5 a.m. on July 12, 2012. Created using Stellarium.
Note Aldebaran near Venus. Aldebaran is the brightest star in the winter constellation Taurus the bull. Note the Pleiades star cluster above Jupiter. Well worth a look with binoculars.
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.
07/09/2012 – Ephemeris – The constellation of Scorpius the scorpion
Ephemeris for Monday, July 9th. Today the sun will be up for 15 hours and 21 minutes, setting at 9:28. The moon, 1 day before last quarter, will rise at 12:23 tomorrow morning. Tomorrow the sun will rise at 6:07.
There’s a large constellation located low in the south at about about 11 tonight. It’s Scorpius the scorpion. Its brightest star is Antares in its heart, a red giant star, that I get calls about from time to time as being a UFO. It’s due south at 11 this evening. From Antares to the right is a star then a vertical arc of three stars that is its head. The Scorpion’s tail is a line of stars running down to the left of Antares swooping to the horizon before coming back up and ending in a pair of stars that portray his poisonous stinger. There is a beautiful star cluster seen in binoculars at that first bend in the tail that is unfortunately too low to appreciate from this far north. I was very impressed with it when spotting it from the Florida Keys.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The constellation Scorpius at 11 p.m. on July 9, 2012. Created using Stellarium.
In the Traverse City area the bottom stars just barely clear the horizon. farther north the constellation will not fully rise above the southern horizon.
The star cluster mentioned is near the star closest to the south compass point in the view above.
NGC6231 – a great binocular star cluster visible from south of Michigan. Created using Stellarium.
In this view there is a hint of ever more stars visible in a small telescope. This recreation doesn’t do it justice.
07/05/2012 – Ephemeris – The Summer Triangle
Ephemeris for Thursday, July 5th. Today the sun will be up for 15 hours and 26 minutes, setting at 9:30. The moon, 2 days past full, will rise at 10:37 this evening. Tomorrow the sun will rise at 6:04.
Now that summer is here, the asterism or informal constellation called the Summer Triangle can be seen high in the east as it gets dark. Highest of the three bright stars is Vega in the constellation Lyra the harp, whose body is seen in a narrow parallelogram nearby. The second star of the triangle is Deneb lower and left of Vega, It appears dimmer than Vega because its is by far the most distant of the three. The third star of the Summer Triangle is seen farther below and right of Vega. It is Altair in Aquila the eagle, and the closest. Altair is 16.7 light years away, Vega is 25 light years while Deneb may be a whopping 1,550 light years away. [One light year is 6 about trillion miles. That’s 6 with 12 zeros after it.]
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location. Bracketed text was omitted from the broadcast due to time constraints.
Addendum
The Summer Triangle July 5, 2012 at 11 p.m. Created using Stellarium and The Gimp.
07/04/2012 – Ephemeris – The earth at aphelion
Ephemeris for Independence Day, Wednesday, July 4th. Today the sun will be up for 15 hours and 27 minutes, setting at 9:30. The moon, 1 day past full, will rise at 10:02 this evening. Tomorrow the sun will rise at 6:03.
Today, Independence Day the earth is at its greatest distance from the sun or about 94.5 million miles from the sun. It doesn’t do much to weaken the strength of sunlight, as you will find out when you go to the beach, But, occurring in summer, makes summer the longest season by a several days over winter. Our calendar tries to keep up with the seasonal or tropical year, while the earths revolution from its farthest or aphelion point to the next is slightly longer. Back in 1776 at the founding of our country the earth was farthest from the sun on June 30th. As we go more centuries into the future summer will get even a bit longer. But remember the poor Aussies whose winter will also get longer.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The orbits of the inner planets. (P)erihelion – (A)phelion
Perihelion is the closest point in an orbit to the sun, while aphelion is the farthest. The earth and Venus have the most circular orbits while Mars and Mercury have markedly elliptical orbits.
07/03/2012 – Ephemeris – How Curiosity will land on Mars
Ephemeris for Tuesday, July 3rd. Today the sun will be up for 15 hours and 28 minutes, setting at 9:30. The moon, at full today, will rise at 9:21 this evening. Tomorrow the sun will rise at 6:03.
At 1:31 on the morning of August 6th our time the Curiosity Rover will land on Mars. The entry, descent and landing of the rover will take just 7 minutes from first encountering the martian atmosphere. The planning to land this nearly one ton lander on Mars was enormous. There’s a heat shield to initially slow the spacecraft, then there is a parachute to slow it more. It will be on the parachute for a maximum of 90 seconds. Then 8 rockets will slow the rover more. These are on the descent stage with the rover tucked underneath. At the proper altitude the descent stage will lower the rover to the ground by cable, then fly off to crash some distance away. This isn’t the half of it. Check out the planetary dot org blog section for more details.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
How Curiosity Will Land – Part 1
How Curiosity Will Land – Part 2
Youtube video: “Challenges of Getting to Mars: Curiosity’s Seven Minutes of Terror”
06/29/2012 – Ephemeris – Preview July skies
Ephemeris for Friday, June 29th. Today the sun will be up for 15 hours and 31 minutes, setting at 9:31. The moon, 3 days past first quarter, will set at 2:58 tomorrow morning. Tomorrow the sun will rise at 6:00.
Lets preview July’s skies. The sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 29 minutes Sunday to 14 hours 40 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the sun at local noon, when the sun is due south will decrease from 68 degrees today to 63 degrees at month’s end. The sun will be a degree lower in the Straits area. Despite the warmth, the earth will reach its greatest distance from the sun on Wednesday the 4th. It’s a time to slow down and appreciate the wonderful stars of summer.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
06/28/2012 – Ephemeris – Mercury near greatest elongation from the sun
Ephemeris for Thursday, June 28th. Today the sun will be up for 15 hours and 31 minutes, setting at 9:31. The moon, 2 days past first quarter, will set at 2:16 tomorrow morning. Tomorrow the sun will rise at 6:00.
Saturday will be the greatest eastern elongation of Mercury from the sun. It’s a whopping 26 degrees angle east from the sun. Mercury has a markedly elliptical orbit. And when we have a spring eastern elongation, its around 18 degrees from the sun. The best western elongations for us are in the autumn when again the elongation angle is 18 degrees. I won’t go into the why of all this here. But we’re getting an extra good view of this tiny planet. The best time to look for Mercury starts about 10:15 p.m. and ends about 10:45 when Mercury is too close to the horizon. The stars Pollux and Castor of Gemini will appear just to the right of Mercury, and will provide a check that you really have found it.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Mercury with the bright stars Pollux and Castor at 10:30 p.m. June 28, 2012. Created using Stellarium.
06/27/12012 – Ephemeris – Where are the bright planets this week?
Wednesday, June 27th. Today the sun will be up for 15 hours and 32 minutes, setting at 9:31. The moon, 1 day past first quarter, will set at 1:40 tomorrow morning. Tomorrow the sun will rise at 5:59.
Let’s see what’s happening with the bright planets for this week. Mercury is in the evening sky but very low in the west northwest about 45 minutes after sunset. It will set at 11:04 p.m. Mars, with its unmistakable bright reddish color, is in the west southwest in the evening entering the constellation of Virgo the virgin. Mars will be setting in the west at 1:15 a.m. Saturn will be in the south southwest above the bright star Spica now. It will set at 2:21 a.m. Jupiter, now a morning planet will rise at 3:53 a.m. in the east northeast. Venus, is now seen below Jupiter after it rises at 4:23 a.m. [They are striking in telescopes with Venus as a large thin crescent, and Jupiter with its cloud bands and satellites.]
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location. Bracketed text was omitted from the audio program due to time constraints.
Addendum
Mercury, Mars and Saturn at 10:30 p.m. on June 27, 2012. Created using Stellarium.
The eastern sky with Jupiter and Venus. at 5:15 a.m. June 28, 2012. Created using Stellarium.
