2021, April 8: Mars Nears Bull’s Horns

April 8, 2021: In the evening sky, Mars approaches the Bull’s horns in the western sky after sunset.  The planet is now higher than Betelgeuse, Orion’s second brightest star.

by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 6:21 a.m. CDT; Sunset, 7:24 p.m. CDT.  Check local sources for sunrise and sunset times for your location.

One hour after sunset, Mars is about halfway up in the west.  It is marching eastward in Taurus.  It is now well-above the “V” of Taurus made by Aldebaran and the Hyades star cluster.

The planet is moving toward the Bull’s horns, Elnath and Zeta Tauri (ζ Tau on the chart).

This evening Mars is 4.2° to the lower left of Elnath and 5.2° to the lower right of Zeta Tauri.

Within the next week, Mars moves between the horns.  Later in the month it moves into Gemini.

Notice that Mars is now a little higher in the sky than Betelgeuse, the second brightest star in Orion and the tenth brightest star in the skies of Earth.  The star is variable in its brightness. During the past two years the star has dimmed noticeably, becoming dimmer than normal during the stars variable pattern.  It has been the subject of speculation of whether it is about to brighten and end its stellar life as a supernova.

Possibly, the star has been shedding dust particles into space that slightly block the star’s light to make it dim in our sky.

In recent articles, the diagrams for Mars have not been including Betelgeuse.  For this evening’s chart, we shift the window southward to include Betelgeuse and omit Capella.

Betelgeuse is noticeably brighter than Mars.  Look to the star’s upper right and above Aldebaran for Mars.

Here’s more about Mars during 2021.

Read about Mars during April.

Detailed Note: One hour before sunrise, Jupiter is nearly 10° above the east-southeast horizon.  Saturn is 12.7° to the upper right of the Jovian Giant.  In the starfield, Jupiter is 2.1° to the upper left of Deneb Algiedi, while Saturn is 2.2° to the upper right of θ Cap. During bright twilight, 30 minutes later, the crescent moon (26.2d, 13%) is nearly 5° up in the east-southeast, over 14° to the lower left of Jupiter. Use a binocular to find them in bright twilight.  In the evening one hour after sunset, Mars – the lone bright planet in the evening sky – is moving between the horns of Taurus. The Red Planet – about halfway up in the west – is 4.2° to the lower left of Elnath (Northern Horn) and 5.2° to the lower right of Zeta Tauri (Southern Horn, ζ Tau, m = 3.0).

Read more about the planets during April 2021.