05/19/2016 – Ephemeris – Daylight Saving Time in West Michigan
Ephemeris for Thursday, May 19th. Today the Sun will be up for 14 hours and 59 minutes, setting at 9:09. The Moon, 2 days before full, will set at 5:49 tomorrow morning. Tomorrow the Sun will rise at 6:08.
It is nearing summer and the powers that be have bequeathed on us daylight saving time, even starting it before the end of winter since 2007. It is a thing that amateur astronomers hate. This time of year through the end of July the Sun just sets too late, and if one has a day job, it’s nearly impossible to stay up long enough to start observing at 11 p.m. or midnight, and be bright-eyed and bushy-tailed the next morning. Nautical twilight, when the sea horizon is no longer discernible ends at 10:28 p.m. tonight, and astronomical twilight, when it’s pitch dark, ends at 11:19. It gets worse the farther north and west you go in the Eastern time zone. At least this year we have three planets to entertain us in the evening twilight.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Our place in the Eastern Time Zone. Source http://www.nationsonline.com. If you are using Firefox right-click on the map and select View Image to enlarge.
We are near longitude W 86°. Our Eastern Standard time meridian is W 75°, which runs through Philadelphia, which I’ve added to the map, southwest of New York. With 15° per hour that makes that 44 minutes behind Philadelphia. Theoretically time zones should extend 30 minutes on either side of a standard time meridian.
During daylight time our time meridian is W 60°, which is off the map. That meridian just ticks the eastern end of Nova Scotia in Canada. For us near 45° north latitude astronomical twilight ends shortly after midnight.
05/18/2016 – Ephemeris – Three bright planets and the Moon grace the evening sky
Ephemeris for Wednesday, May 18th. Today the Sun will be up for 14 hours and 57 minutes, setting at 9:08. The Moon, 3 days before full, will set at 5:19 tomorrow morning. Tomorrow the Sun will rise at 6:09.
Let’s see what the bright naked eye planets are up to. Jupiter is in the south in the early evening, moving to the southwest. It will set at 3:28 a.m. It’s below the stars of Leo this year. Binoculars can make out some of Jupiter’s moons, but a telescope is required to see all four bright moons and Jupiter’s cloud features. Mars will rise at 9:26 p.m. in the east-southeast. It’s above and right of its look-a-like star Antares, whose name means Rival of Mars. Mars is getting closer to the Earth now, only 48 million miles (77 million km) away. It will be closest to the Earth on the 30th. Saturn will rise at 10:11 p.m. in the east-southeast. It’s to the left of Mars, and once it’s been up for an hour is a beautiful sight in any telescope.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon, Jupiter, Mars and Saturn at 11 p.m. May 18, 2016. Created using Stellarium.
The Moon as it might be seen in binoculars at 11 p.m., May 18, 2016. Created using Stellarium.
Jupiter and its moons as they might be seen through a telescope at 11 p.m. May 18, 2016. It’s 38.7″ in equatorial diameter. The Great Red Spot will cross the planet’s central meridian at 11:38 p.m. Created using Cartes du Ciel (Sky Charts).
Mars as it might be seen in a large telescope with high power at 11 p.m. May 18, 2016. Mars apparent diameter is 18.2″. The central meridian will be 248.08 degrees. Syrtis Major is the large feature in the north near the polar cap. Created using Cartes du Ciel (Sky Charts).
Saturn and its moons at 11 p.m. May 18, 2016. The apparent diameter of the planet will be 18.4″. The rings span 42.8″, a bit larger than the apparent diameter of Jupiter. Created using Cartes du Ciel (Sky Charts).
Planets at Sunrise and Sunset of a single night starting with sunset on the right on May 18, 2016. The night ends on the left with sunrise on May 19. If you are using Firefox right-click on the image and select View Image to enlarge the image. That goes for all the large images.
05/17/2016 – Ephemeris – Three heliocentrists memorialized on the Moon tonight
Ephemeris for Tuesday, May 17th. Today the Sun will be up for 14 hours and 55 minutes, setting at 9:07. The Moon, half way from first quarter to full, will set at 4:50 tomorrow morning. Tomorrow the Sun will rise at 6:10.
Tonight the gibbous Moon boasts the uncovering of three craters from lunar night whose namesakes were pioneers in putting forth the heliocentric theory. That is that the Earth and the other planets revolved about the Sun. Out the longest, and making the biggest splash is the crater Copernicus, named for the Polish cleric whose book On the Revolution of the Heavenly Spheres gave a new meaning to the word revolution, that is upheaval. The crater Kepler is about two-thirds the way from Copernicus and the terminator, named after the astronomer who discovered that the plants orbit the Sun in elliptical paths. Finally just catching sunlight is Aristarchus who in the 4th century BC first proposed a heliocentric solar system.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Three heliocentrists on the Moon at 10 p.m., May 17, 2016. Created using Virtual Moon Atlas.
05/16/2016 – Ephemeris – The Sun rises on the Bay of Rainbows
Ephemeris for Monday, May 16th. Today the Sun will be up for 14 hours and 53 minutes, setting at 9:06. The Moon, 3 days past first quarter, will set at 4:23 tomorrow morning. Tomorrow the Sun will rise at 6:11.
One of my favorite lunar formations is creeping into sunlight on the Moon this evening. Look to the upper left edge of the moon tonight. The large sea or dark area of the Moon, the Man in the Moon’s right eye as he’s looking at us is Mare Imbrium, the Sea of Showers. At the top left edge of that sea is a large notch. And keeping with of seas these of the first telescopic astronomers its name is Sinus Iridium, or Bay of Rainbows, a colorful name for something as colorless as the rest of the Moon. The terminator which is the sunrise line will be cutting across that bay, illuminating the semicircular mountain ring that surrounds it before all of the floor is illuminated. It can be seen in binoculars or a small telescope.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Image showing the Moon tonight at 10 p.m., May 16, 2016 (2 hr, May 17, 2016 UT) with Sinus Iridium (Bay of Rainbows) just coming into sunlight. Created using the Virtual Moon Atlas.
05/13/2016 – Ephemeris – GTAS Astronomy Day tomorrow
Ephemeris for Friday, May 13th. Today the Sun will be up for 14 hours and 46 minutes, setting at 9:02. The Moon, at first quarter today, will set at 2:59 tomorrow morning. Tomorrow the Sun will rise at 6:15.
The Grand Traverse Astronomical Society will host a public viewing night for Astronomy Day tomorrow night, that’s Saturday the 14th, starting at 9 p.m. It will be at Northwestern Michigan College’s Joseph Rogers Observatory. If its clear the slightly gibbous moon will be featured along with Jupiter, Mars and the ringed planet Saturn and other wonders of the spring sky. The observatory is located south of Traverse City, on Birmley Road between Garfield and Keystone roads. For the society these, twice monthly star parties at the observatory and sidewalk astronomy outings by members, to the Sleeping Bear Dunes National Lakeshore and other locations are what they do.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Other thoughts
I was checking out the Solar and Heliospheric Observatory (SOHO) LASCO C3 animation and Venus is making an entrance from the right as it heads for superior conjunction on June 6. June 6? Hmm. Wasn’t that last transit or Venus on June 5th 2012. We and Venus should be near the line of nodes again, where the planes of our respective orbits cross. I cranked up Stellarium, and sure enough the Sun will occult Venus that day… Not that we could see it.
05/12/2016 – Ephemeris – The Moon tonight
Ephemeris for Thursday, May 12th. Today the Sun will be up for 14 hours and 44 minutes, setting at 9:01. The Moon, 1 day before first quarter, will set at 2:26 tomorrow morning. Tomorrow the Sun will rise at 6:16.
The moon tonight is a fat crescent. In binoculars the small Sea of Crises is prominently located as a gray patch at the edge of the moon. The Sea of Fertility is below it, while the sea of Tranquility is between them and near the terminator, the sunrise line on the moon. In telescopes there are three craters south of Tranquility, most prominent of which is Theophilus. With its prominent central peak. Farther to the north of Crises and near the partially exposed Sea of Serenity is the crater Posidonius, larger than Theophilus, but has a double crater wall on one side. Larger telescopes can see cracks in its floor . It has no central peak, and shows its age of maybe three and a half billion years.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon at 10 p.m. May 12, 2016. Created using Virtual Moon Atlas.
05/11/2016 – Ephemeris – Three of the bright planets are seen before midnight
Ephemeris for Wednesday, May 11th. Today the Sun will be up for 14 hours and 41 minutes, setting at 9:00. The Moon, 2 days before first quarter, will set at 1:48 tomorrow morning. Tomorrow the Sun will rise at 6:17.
Let’s see what the bright naked eye planets are up to. Mercury is now officially in the morning sky but too close to the Sun to be seen. Jupiter is in the south in the early evening, and will pass due south at 9:22 p.m., and will set at 3:55a.m. It’s below the stars of Leo this year. Binoculars can make out some of Jupiter’s moons, but a telescope is required to see all four bright moons and Jupiter’s cloud features. Mars will rise at 10:33 p.m. in the east-southeast. It’s still above its look-a-like star Antares, whose name means Rival of Mars. Mars is getting closer to the Earth now, only 50 million miles away It will be closest on the 30th. Saturn will rise at 10:41 p.m. in the east-southeast. It’s just left of Mars.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The evening sky tonight at 11:30 p.m. Created using Stellarium.
05/10/2016 – Ephemeris – The lunar Sea of Crises
Ephemeris for Tuesday, May 10th. The Sun rises at 6:19. It’ll be up for 14 hours and 39 minutes, setting at 8:59. The Moon, 3 days before first quarter, will set at 1:04 tomorrow morning.
Tonight the Moon shows one remarkable sea: Mare Crisium or the Sea of Crises. It is a large gray basin. The largest feature visible in binoculars. Because it’s near the Moon’s limb or edge it is foreshortened into an ellipse, with the long axis running north and south. In actuality it is elliptical with the long axis east and west. It looks funny on a geologic map of the whole moon or a Moon globe. Its dimensions are 345 by 375 miles (570 by 620km). It’s really a crater as are all seas whose impact asteroid reached down to the Moon’s magma and caused lava to well up to produce the flat floor. When the sunlight is low as it is now wrinkle ridges will appear showing where successive lava flows have stopped and solidified.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon’s approximate orientation and phase at May 10, 2016. Created using Stellarium.
Some views of the festivities at the Sleeping Bear Dunes National Lakeshore Dune Climb for the transit of Mercury earlier today
Mercury and some sunspots at 8:30 a.m. through my telescope. Thought I’d take a shot before we had visitors. C8 Cassigrainian focus, ISO 100, 1/100 second.
Checking the transit via the “Dobinator” through the Grand Traverse Astronomical Society’s (GTAS) 25 inch Dobsonian stopped down with an 8″ solar filter.
Viewing the transit through my Celestron C8.
Kids viewing the transit through the society’s Lunt hydrogen alpha solar telescope.
Youngster viewing the transit through Emmett Holmes’ 13″ homemade Dobsonian telescope and Poncet tracking mount.
Credit: Bob Moler
05/09/2016 – Ephemeris – The transit of Mercury is today!
Ephemeris for Monday, May 9th. The Sun rises at 6:21. It’ll be up for 14 hours and 36 minutes, setting at 8:58. The Moon, 3 days past new, will set at 12:12 tomorrow morning.
In less than an hour from now the planet Mercury will begin to cross the face of the Sun. It starts at 7:12 a.m. The transit will end at 2:42 this afternoon. Mercury is a tiny planet making a tiny dot against the face of the Sun, and smaller than any sunspot. If it’s clear or when its clear come out and view part of the transit. The Northwestern Michigan College’s Rogers Observatory will be open for that period. Also telescopes with be stationed at the Dune Climb at the Sleeping Bear Dunes National Lakeshore by yours truly to view the transit. The event is not visible to the naked eye and dangerous to even attempt. If you miss this transit, there will be another in 2019, 3 ½ years from now. After that, a Mercury transit visible from here will have to wait until 2049.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The track of Mercury across the face of the Sun. Mercury will travel from upper left to lower right. Mercury will not be visible until it impinges upon the disk of the Sun. Credit IOTA’s program Occult4.
Transit visibility map with added captions to make it more readable. Credit United States Naval Observatory, The Astronomical Almanac Online.
For more information see my prior day’s posts.
