9pm – 11pm       Planetary and Deep Sky observing

The moon will not be visible tonight.

Here is some information on other celestial objects that we may observe:

Planets

Saturn will only be 17 degrees high in the southwest at 9pm, but should still be viewable for a little while. The illustration below shows the positions of the brightest of its 62 moons. Interestingly enough, Titan and Jupiter’s moon Ganymede are both larger than the planet Mercury.

Neptune will be 33 degrees up at 10pm, and rising higher. It’s largest moon, Triton, should be seen in the 20″ scope. Neptune was discovered September 23,1846.

Graphics above courtesy of Starry Night (R) Orion Special Edition, Version: 6.2.3 kcEW, Imaginova (R) Corp.

Double Stars

Many stars are double, and all have their own unique combinations of brightness, colors, and separation. Two examples overhead are Alberio and 61 Cygni. Alberio is 386 light years away and shows a quite vivid color contrast. 61 Cygni is only 11 LY from us, and so is one of the closest star systems. It’s components are evenly matched with a beautiful gold-orange color, in a rich star field.

Worth mentioning is the “summer triangle”, a naked eye arrangement of 3 bright stars. Altair (in Aquila) is close by at 17 light years, and so is Vega (in Lyra) at 25 LY. Deneb (in Cygnus) is different; it’s distance is hard to pin down and estimates range from 1500 to 7000 LY. In any case, it’s one of the brightest stars in the entire Milky Way galaxy at about 200,000 times the sun’s luminosity.

Open Clusters

M11 (below) and NCG 457 (the ET cluster) are two favorites. If you see NGC 457 in the eyepiece, you’ll notice the uncanny resemblance to “ET”.

Planetary Nebula

Favorable to observe because their surface brightness can be quite high, so they shine through light pollution. M27 and M57 are shown below, two others are NGC 6826 (the Blinking Planetary) and NGC 7662 (Blue Snowball).

Globular Clusters

Many are visible this time of year, M13 (below) and M92, both in Hercules are good examples.

Galaxies

The Andromeda Galaxy (M31) will be visible in the east, and is the brightest galaxy in the northern sky, also close by at 2 million light years.

M27 and M13 courtesy Al Johnson, M57, M11, and M31 courtesy Joe Roberts, both ASGH members. See also Joe’s website.