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Astronomical Data and Information

Lake of the Woods - Copyright 1999 M.Fuhs

 The July setting sun casts its brilliance
over Lake of the Woods, Ontario

 

The principle of Rayleigh Scattering explains the red or orange sunsets.  As the sun moves lower in the sky, its light has to travel through "more" of the atmosphere since the sun is at a much lower angle.  In fact at the horizons on a level plane, the atmosphere is about 40 times more thick than it is directly overhead.  Particles and molecules in the atmosphere will scatter out the shorter wavelengths (blue in the color spectrum) more easily than longer ones (red).  Thus, we are left with the reddish portion of the light spectrum to see. 

 

 

 

 

 

Season Starting Dates and Times
2020
Spring
Thursday, Mar 19
10:49 PM CDT
Summer
Saturday, Jun 20
4:43 PM CDT
Autumn
Tuesday, Sep 22
8:30 AM CDT
Winter
Monday, Dec 21

4:02 AM CST

 

 

2020 Major Meteor Showers
Shower
Period of Activity
Peak Dates
ZHr*
Comments 

Lyrids

April 16 to April 25

Apr 21st and 22nd

 

18

The Lyrids' peak is somewhat brief.  Look in the late evening of April 21st to the early morning hours of April 22nd.  The best viewing will be before sunrise. However, a waning gibbous moon will interfere the brightest meteors during the peak dates. The radiant for this shower is near the border of the constellations Lyra and Hercules.     

Eta Aquariids

April 19 to May 28

May 4th and 5th

 

 

40

Peak time occurs for a couple of hours just before sunrise on May 5th. This shower favors the southern hemisphere and the southern latitudes of the northern hemisphere as the radiant is from near the star Eta in the constellation Aquarius.  In the northern U.S. and Canada, less than 10 to 20 meteors per hour can be expected whereas the shower is quite spectacular in the southern hemisphere.  The moon will be near full; therefore the moon will interfere with the peak this year. 

Delta Aquariids
July 12 to August 23
Jul 28th and 29th
 
15-20
Peak time occurs from the late evening July 28th through the early morning of July 29th.  Similar to the Eta Aquariids, this shower favors the southern hemisphere and the southern latitudes of the northern hemisphere as the radiant is near the star Delta in the constellation Aquarius.  In the northern U.S. and Canada, less than 15 to 20 meteors per hour can be expected and the meteors are typically rather faint.  
Perseids
July 17 to August 26

Aug 11th to Aug 12th

 

50-75
The peak of the Perseids will occur from the evening of August 11th when it gets dark, to the early morning hours of August 12th.  Part of this year's peak time will occur at night for North America from 10 pm CDT on the 12th, to 4 am CDT on the 13th.  The radiant is in the constellation Perseus but meteors from the Perseids are seen all over the sky. The last quarter phase of the moon will provide quite a bit of interference as it will be in the same part of the sky as the radiant. The best viewing will be on a dark sky away from the radiant. 

Orionids

October 2 to November 7

Oct 20th to Oct 21st

10-25

Peak viewing will be on the night of October 20-21. The moon will not interfere the activity because it will be in a crescent phase. The radiant is north of Orion's red giant star, Betelguese, but the Orionids can occur anywhere in the sky.

Leonids

November 6 to November 30

Nov 16th to Nov 17th

15-20

One of the weakest showers of this year. The peak this year will favor the evening hours of November 16th through the early morning of November 17th.  The moon will only be 5% full; therefore, it will not interfere this activity. The radiant of the Leonids emanate from the constellation Leo. 

Geminids
December 4 to December 17
Dec 13th to Dec 14th
100-120
Peak viewing will be on the evening of December 13th into the morning hours of December 14th.The best viewing will occur after 9 pm CDT on December 13th, with a peak around 2 am CDT.  Although not as noteworthy as the Perseids, the Geminids are actually usually the best and most consistent shower each year.  The problem is being winter in North America, many times the Geminids are obscured by clouds.  The Geminids' radiant is near the twin's heads in Gemini, but will occur anywhere in the sky.
Quadrantids December 27,2020 to January 10, 2021
Jan 2nd to Jan 3rd, 2021
 
120 Peak time is in the evening of January 2nd to early morning January 3rd.  This meteor shower always favors northerly latitudes.  This is because the radiant is near the handle of the Big Dipper in the northern night sky, however meteors with this shower can occur anywhere.  The Quadrantids peak only lasts for a few hours and furthermore this year, a near full moon will provide major interference with this shower.  Therefore observers will see only the brightest meteors with rates much less than 50-100 per hour.

 

DEFINITIONS:

*ZHr =  is the maximum numbers of meteors expected per hour at Zenith (straight up in sky) and under a very dark sky.  Average meteor rate can                 be expected to be less (much less in an urban environment.)

Radiant=  A point in the sky in which meteors appear to originate.

 

 

 

  

These pages were developed in response

to public inquiries concerning astronomical data.