Highland Road Park Observatory

THE EDGE OF NIGHT
(Fall Session)

Friday 16 November from 4:45 pm to 6:45 pm CST
No admission fee. For all ages.
Binoculars strongly encouraged.

It’s not light, it’s not dark. It’s that special time called twilight, and HRPO wants to introduce you to it!

*Are all sections of the sky the same shade of blue?
*Which stars are seen first?
*Are Mercury☿ and Venus♀ or the Moon out?
*Is that moving object a plane, a satellite or space debris?
*How much actual darkness should I expect in a light-polluted city when twilight has passed?

There is no other time like twilight. Bring it into your life!

  • 4:45 pm to 5:15 pm = Mercury☿ viewing
  • 4:45 pm to 6:45 pm = Venus♀ viewing
  • 5:06 pm = “civil twilight” begins (search for crepuscular rays)
  • 5:33 pm = “civil twilight” ends; “nautical twilight” begins
  • 5:36 pm to 5:42 pm = magnitude 2.3 pass of a Chang Zheng 4B rocket
  • 6:00 pm to 7:00 pm = Saturn♄ viewing
  • 6:01 pm to 6:11 pm = magnitude 1.9 pass of a Chang Zheng 4C rocket
  • 6:02 pm = “nautical twilight” ends; “astronomical twilight” begins
  • 6:07 pm to 6:09 pm = magnitude 0.1 pass of USA 161
  • 6:15 pm to 6:45 pm = Mars♂ viewing
  • 6:31 pm = “astronomical twilight” ends

{The various twilights will be explained.}

Celestial Objects in Order of Brightness (but not necessarily appearance):

The Moon [-12.3] / Mars♂ [-0.3] / Vega [0.0] / Capella [0.1] / Saturn♄ [0.5] / Mercury☿ [0.6] / Altair [0.8]/ Fomalhaut [1.1] / Pleiades Star Cluster [1.2] / Deneb [1.3] / Polaris [2.0]

NOTE: Due to the Natural Sky Conference, this Edge of Night session was postponed one week.

This program pre-empts the Friday Night Lecture Series on…
*the last Friday in spring before Daylight Time begins
*the Friday during the week of Independence Day
*the first Friday in fall after Daylight Time ends

HRPO 2015 09 15 1901

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Updated by Frederick J. Barnett on Friday, October 26, 2018, 02:09 PM.