04/29/2016 – Ephemeris – Let’s preview the merry skies of May
Ephemeris for Arbor Day, Friday, April 29th. The Sun rises at 6:34. It’ll be up for 14 hours and 10 minutes, setting at 8:45. The Moon, at last quarter today, will rise at 3:01 tomorrow morning.
Sunday starts the month when the promise of spring is finally fulfilled. Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 16 minutes Sunday to 15 hours 20 minutes on the 31st. The altitude, or angle, of the Sun above the southern horizon at local noon will ascend from 60 degrees Sunday to 67 degrees at month’s end. The altitude of the sun in the Straits area will be a degree lower than that but your daylight will be a few minutes longer. The big event of May will be the transit of the tiny planet Mercury across the face of the Sun on May 9th. I’ll have more on that next week. Also Mars will be in opposition from the Sun on the 22nd which due to its elliptical orbit will actually be closest to us 8 days later on the 30th at 46.779 million miles (75.284 million km).
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
May Star Chart
The planets and stars are plotted for the 15th at 11 p.m. EDT. That is chart time. Note, Traverse City is located approximately 45 minutes behind our time meridian. (An hour 45 minutes behind our daylight saving time meridian.) To duplicate the star positions on a planisphere you may have to set it to 1:45 earlier than the current time.
Evening nautical twilight ends at 10:00 p.m. EDT on the 1st, increasing to 10:43 p.m. EDT on the 31st.
Morning nautical twilight starts at 5:20 a.m. EDT on the 1st, and decreasing to 4:38 a.m. EDT on the 31st.
Add a half hour to the chart time every week before the 15th and subtract a half hour for every week after the 15th. Before the 13th also subtract an hour for Standard Time.
For a list of constellation names to go with the abbreviations click here.
- Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star
- A leaky Big Dipper drips on Leo
- Follow the arc of the handle of the Big Dipper to the star Arcturus
- Extend the ac to a spike to point to Spica
Calendar of Planetary Events
Credit: Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)
To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html
Times are Eastern Time. Some additions made to aid clarity.
Date Time Event May 01 Su Venus: 9.8° W 02 Mo 9:27 p.m. Moon Descending Node 04 We 2:45 p.m. Eta Aquarid Shower: ZHR = 60 06 Fr 12:14 a.m. Moon Perigee: 357800 km 06 Fr 3:30 p.m. New Moon 08 Su 4:21 a.m. Moon-Aldebaran: 0.5° S 09 Mo 7:12 a.m. Mercury transit begins 09 Mo 10:57 a.m. Mercury mid-transit 09 Mo 2:42 p.m. Mercury transit ends 09 Mo 5:54 p.m. Moon North Dec.: 18.4° N 13 Fr 1:02 p.m. First Quarter 14 Sa 3:06 a.m. Moon-Regulus: 2.5° N 15 Su 5:30 a.m. Moon-Jupiter: 2.2° N 15 Su 4:39 p.m. Moon Ascending Node 18 We 6:06 p.m. Moon Apogee: 405900 km 21 Sa 5:15 p.m. Full Moon 22 Su 7:15 a.m. Mars Opposition 22 Su 5:59 a.m. Moon-Saturn: 3.5° S 24 Tu 7:16 a.m. Moon South Dec.: 18.5° S 29 Su 8:12 a.m. Last Quarter 30 Mo 12:45 a.m. Moon Descending Node 30 Mo 5:36 p.m. Mars closest to the Earth 0.50321 AU Jun 01 We Venus: 1.5° W
Transit of Mercury
May 9, 2016 7:12 a.m. (11:21 UT) to 2:42 p.m. (18:42 UT)