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In the Sky This Month -September- by Rick Wagner

In the Sky This Month by Rick Wagner
2 Sep - Full Moon 01:22EDT
5 Sep - Moon glides by just one apparent lunar diameter south of Mars through the evening
10 Sep - Last Quarter Moon 05:26EDT
11 Sep - Neptune at opposition (mag 7.8)
11 Sep - asteroid 11 Fortuna at opposition (mag 9.2)
14 Sep - double shadow transit on Jupiter 02:57EDT
17 Sep - New Moon 07:00EDT
17 Sep - very difficult ~12.5hr old Moon a couple of degrees above the western horizon just after sunset
22 Sep - Autumn begins with the equinox at 09:31EDT
23 Sep - First Quarter Moon 21:55EDT
30 Sep - asteroid 68 Leto at opposition (mag 9.5)
Late Sep gives us a chance to see all 8 major planets in one night.  The biggest challenge will be to see Mercury (mag -0.1) low in the bright twilight sky very soon after sunset (if you don’t bag this one you can give up on this challenge and get on with other observing.)  It will be about 25º left of the Sun.  Try this challenge on the 18th or 19th when the very thin crescent Moon may help guide you to Mercury (5.5º down and left of the Moon on the 18th, 12.5º down and to the right on the 19th.)  For an additional challenge see if you can catch mag 1 Spica about 3º left of Mercury.  Binoculars will be very helpful in pulling both of these objects out of the twilight.
Jupiter and Saturn will be obvious almost directly south by the end of twilight, quite bright and both slightly yellowish white.
Neptune is the only one that definitely will require optical aid - a pair of binoculars will suffice.  About 14º SE of the water jar of Aquarius look for 4th mag phi Aquarii, then go 1.7º ENE to find Neptune.  There are several stars of similar brightness in the area so you’ll want a small finder chart (see pg 229 of your Observer’s Handbook or look online.)  See if you can detect its bluish colour - easier in a telescope.
By 22:00EDT very bright reddish Mars will be well up and obvious in the ESE.  It is by far the brightest object in the sky in that direction and its fire-light glow is diagnostic.  Mars is getting nearly as large as it ever appears in our sky - well worth a detailed look in a telescope.  Look for the small bright white dot that is its south polar cap.
Uranus is about 15º left of Mars and about 1700x fainter.  It forms a nice isosceles triangle with the upper two stars of the circlet of Pisces.  If you have good eyes and a good sky you should be able to see it with the unaided eye but binoculars will make it much easier and may make its greenish colour noticeable.  Again, you’ll want to check the finder chart on pg 228 of your Observer’s Handbook or online.
Finally close out the night with very bright white Venus rising in the ENE about 03:30EDT, sitting on the front paws of Leo the Lion.  
And that makes seven.  Oh, yeah, don’t forget to look down to see the eighth and the only major planet on which humans have ever walked.

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