2021, June 15-22: Evening Star Venus, Mars


June 15 – June 22, 2021:  Brilliant Evening Star Venus shines in the west-northwest after sunset.  It continues to close the distance to Mars.  Venus shines from Gemini, beneath Castor and Pollux.  Mars marches eastward in Cancer, approaching the Beehive star cluster.

Chart Caption – 2021, June 17: Venus is below Castor, one of the Gemini Twins. Mars is 15.0° to the upper left of brilliant Venus.

by Jeffrey L. Hunt

Step outside on the next clear evening.  Brilliant Evening Star Venus shines from low in the west-northwest after sunset. The planet sets 93 minutes after sunset on June 15 and about a minute later each evening.

Mars is to the upper left of Venus.  The Red Planet is considerably dimmer than it was at the beginning of the year.  Our planet continues to move away from Mars and its reflected sunlight dims as the distance increases.  While the planet is easily within the range of human eyesight an optical assist from a binocular makes locating it easier.

On June 15, the gap from Venus to Mars is 16.2°.  Seven nights later, the distance between the two planets is reduced to 12.0°.  Venus moves eastward along the ecliptic – the plane of the solar system – about twice as fast as Mars.  Earth’s Twin overtakes Mars in about a month.

On the chart above, Venus is 6.9° below Pollux and 15.0° to the lower right of Mars.

The Red Planet is in front of the dim stars of Cancer. 

Cancer is the region between Pollux and Regulus.  The gap between the two bright stars is nearly 40°.  That seemingly empty region of the sky is Cancer.  It has stars dimmer than Mars, and are blotted out by the bright lights of urban and suburban areas.

Chart Caption – 2021, June 15 – June 22: Through a binocular, watch Mars approach the Beehive star cluster. The cluster is in a box made by Gamma Cancri (γ Cnc), Delta Cancri (δ Cnc), Eta Cancri (η Cnc) and Theta Cancri (θ Cnc).

Seemingly hidden within the constellation is the Beehive star cluster.  Mars appears in front of the stellar bunch on June 23.

The image above shows the travel of Mars viewed through a binocular.  On June 15, Mars is 4.6° to the lower right of the star cluster.  At the end of the sequence in the image, the separation is 0.3°.

The cluster appears inside a box made by the dim stars Gamma Cancri (γ Cnc on the chart), Delta Cancri (δ Cnc), Eta Cancri (η Cnc) and Theta Cancri (θ Cnc).  Gamma Cancri’s name is Asellus Borealis, while Delta’s name is Asellus Australis.

Watch Venus move through Gemini and Mars approach the Beehive star cluster during the next several evenings.

Categories: Astronomy, Sky Watching

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