Bob Moler's Ephemeris Blog

Ephemeris for Thursday, January 31st. Today the Sun will be up for 9 hours and 46 minutes, setting at 5:49, and it will rise tomorrow at 8:02. The Moon, half way from last quarter to new, will rise at 5:50 tomorrow morning.

February is the shortest month, even so the daylight hours throughout the month will be getting longer. Daylight hours will increase from 9 hours and 49 minutes tomorrow the first to 11 hours and 6 minutes on the 28th. The sunrise time will decrease from 8:02 tomorrow to 7:22 at month’s end. The sunset times will increase from 5:51 tomorrow to 6:28 on the 28th. Along with that the altitude of the sun at noon will increase from 28 degrees tomorrow to nearly 38 degrees at month’s end. Local noon, by the way for Interlochen and Traverse City is about 12:55 p.m. Mercury has just entered the evening sky and will be visible in twilight after sunset later this month.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addenda

February Evening Star Chart

Star Chart for February 2019 (9 p.m. EST February 15, 2019). Created using my LookingUp program. Click on image to enlarge.

The planets and stars are plotted for the 15th at 9 p.m. EST in the evening and 6 a.m. for the morning chart. These are the chart times. Note that Traverse City is located approximately 45 minutes behind our time meridian. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.

Note the chart times of 9 p.m. and 6 a.m. are for the 15th. For each week before the 15th add ½ hour (28 minutes if you’re picky). For each week after the 15th subtract ½ hour. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog.

February Morning Star Chart

Star Chart for February mornings 2019 (6 a.m. EST February 15, 2019). Created using my LookingUp program. Click on image to enlarge.

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.
• Follow the arc of the handle of the Big Dipper to the star Arcturus, and
• Extend like a spike to Spica,
• The Summer Triangle is in red.

Twilight Limits, Nautical and Astronomical

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2019/09/27/

NASA Calendar of Planetary Events

All event times are given for UTC-5:00: Eastern Standard or Daylight Time

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

If you go to the above site you can print out a list like the above for the entire year or calendar pages for your time zone.

Sun and Moon Rising and Setting Events

Created using my LookingUp for DOS output as HTML.