For the Northern Hemisphere observer, it’s a very close approach. On the 4th, Uranus is 4 degrees north of the Moon; then on the 8th, the cluster M35 shares the stage; on the 13th Venus is 4 degrees south. By the 22nd, the Moon glides by Jupiter and Saturn, as the gas giants close the gap in anticipation of the conjunction on December 21. By the 29th, Mars is once again in the picture, and the Moon is full again on the 31st. This is the smallest full Moon of 2020, as our satellite is at its most distant in its orbit just a few hours earlier.
Mercury is at its greatest elongation east (GEE) as the month begins, but it’s a poor opportunity for northern viewers to spot the speedy planet – the ecliptic is almost horizontal, so Mercury sets about the same time as the Sun. By the 25th, Mercury is at inferior conjunction, right in front of the Sun.
Venus continues as the Morning Star, shining high in the east before sunrise. Something to watch for on the mornings of the 2nd and 3rd is the very close approach of the bright star Regulus in Leo (The Lion). The Moon passes close by on the mornings of the 13th and 14th.
Mars watchers will be paying close attention during October at this closest approach to Earth – 2035 is the next close opposition. Skilled photographers have been getting great images of the Red Planet for a few months already and this close approach will see many photons captured on camera chips over the next while. The last few oppositions have seen dust storms kick up as Mars’s atmosphere heats – some storms completely covered the planet, aggravating photographers attempts at capturing clear images.
Jupiter in prograde motion, sets near midnight now as Earth pulls further away. Watch for the Moon nearby on the 21st and 22nd.
Saturn is following Jupiter, setting in the late evening, and joined by the Moon on the 22nd.
Uranus reaches opposition on the 31st, so it will be directly south at local midnight. The Moon has two opportunities in October to visit the gas planet – the 3rd and the 30th.
Neptune, among the stars of Aquarius, rises in the early evening and sets around 4 a.m. It, too, is joined by the Moon in the 26th.
The zodiacal light is visible in the east before sunrise for the last two weeks of the month.
James Edgar has had an interest in the night sky all his life. He joined The Royal Astronomical Society of Canada in 2000, was National President for two terms, is now the Editor of the renowned Observer’s Handbook, and Production Manager of the bi-monthly RASC Journal. The IAU named asteroid 1995 XC5 “(22421) Jamesedgar” in his honour.
-James Edgar
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