In the Sky this Month for SWFL.
If you are new to the night sky, and have an Android device, such as a tablet or phone, you can find a free app in the Google Play Store, called Sky Map. Sky Map will help you locate objects in the night sky.
Autumnal equinox occurs on the 23rd.
See excellent diagrams of planetary paths & orbits in “Astronomy” magazine, pages 40-41, September 2019.
Moon: 1st Quarter – October 5; Full – October 13; Apogee – October 10; Last Quarter – October 21 (EDT); Perigee – October 26; New– October 28
Mercury (dusk) for most of the month is above and to the left of Venus. Its magnitude is at 0 for the month, while hard to see being low at twilight. It sets less than an hour after the Sun.
On the evening of the 31st, it is about 21⁄2° below Venus, low in the southwest. It quickly fades while approaching solar transit on November 11.
Venus (dusk) sets 1⁄2 hour after sunset at the beginning of the month and an hour afterwards by the end. Its magnitude is -3.9 in the first half of the month and -3.8 during the second half. During the second half of October, it is almost fully lit, but almost at its minimum arc of 10”.
Mars (dawn, looking East) emerges from solar glare during the third week, after being out of view since July. It rises less than an hour before the Sun on the 1st and nearly two hours before on the 31st. Its brightness is merely a 1.8 magnitude and its disk size is about the same as the much more distant Uranus. Note that next year this month Mars will be at its next opposition and appear six times wider. On the 7th, it moves southward in Virgo over the celestial equator and its northern hemisphere has its summer solstice.
Jupiter (dusk – evening, Southwest) is just southeast of the Moon on the 3rd and northwest of Antares at dusk.. It dims a little more this month in magnitude from -2.0 to -1.9, and sets 31⁄2 hours after sunset at the beginning of October and about 21⁄2 hours afterward at the end. See the detailed charts on page 51 in Sky & Telescope, or page 41 of Astronomy, September 2019, showing observation times for Jupiter’s moons.
Saturn (dusk – evening, South) is nearly 30° above the horizon early in October, and about 90° east of the Sun on the 7th. With the rings tilted at just over 25°, this position from the
Sun gives the planet and rings a 3D look. At the beginning of the month it sets at about midnight and at about 10 p.m. by the end of the month. It continues to dim, changing magnitude from +0.5 to +0.6, and its size decreases from 16.8” to 16”.
Uranus, (East-evening; West-morning) high in Aires, reaches its highest point for the year between October 27/28, at opposition, and visible all night. Its midmonth magnitude is +5.7 and spans 3.7”. See https://is.gd/urnep for a finder chart.
Neptune, (Southeast-evening; Southwest-morning) in Aquarius, was at opposition on 10 September, so visible most of the night. See https://is.gd/urnep for a finder
International Space Station:
The Hubble Space Telescope will be visible early evening (7-9 p.m.) the first half of October, and between 6 & 7 a.m. from the last week of the month. See this link for specific times and routes for the HST: http://www.heavens-above.com