Highland Road Park Observatory

THE EDGE OF NIGHT
(Winter Session)

Friday 9 March from 5:30 pm to 7:30 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!

  • 5:45 pm to 6:30 pm = Venus♀ viewing
  • 6:08 pm = “civil twilight” begins (search for crepuscular rays)
  • 6:15 pm to 6:45 pm = Mercury☿ viewing
  • 6:33 pm = “civil twilight” ends; “nautical twilight” begins
  • 7:01 pm = “nautical twilight” ends; “astronomical twilight" begins
  • 7:06 pm to 7:14 pm = magnitude 2.5 pass of Cosmos 1743
  • 7:22 pm to 7:29 pm = magnitude 2.1 pass of ERS-2
  • 7:29 pm = “astronomical twilight” ends

{The various twilights will be explained.}

Celestial Objects in Order of Appearance (with magnitudes):

Venus♀ [-3.9] / Sirius [-1.5] / Mercury☿ [-0.9] / Canopus [-0.7] / Capella [0.1] / Rigel [0.1] / Procyon [0.3] / Betelgeuse [0.5] / Aldebaran [0.8] / Pollux [1.1] / Pleiades Star Cluster [1.2] / Regulus [1.3] / Adhara [1.5] / Castor [1.6] / Polaris [2.0]

NOTE: The 13 April lecture “Wonders of the Spring Sky” is an excellent followup to this session.

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

Back to top


Updated by Frederick J. Barnett on Wednesday, February 21, 2018, 12:11 PM.