September skies will feature harvest moon, Venus, Jupiter

As the Earth moves around the sun, we move into the autumnal equinox and cooler weather for us here in Arizona. With that comes the promise of some great views of our skies!

The journey begins with a discussion of the position of the moon and when and where to view it.

Month No. 9, September, begins with the moon visible in the predawn sky as a thin waning crescent. The moon passes the bright stars Castor and Pollux in Gemini on Friday.

The moon then moves on to its new phase Sept. 7. This is a great time to view many of the faint sky objects that adorn our skies. This includes a view of the Milky Way and many of the star clusters in the heart of the Sagittarius star cloud. Look low in the south around 8 p.m. Arizona time for that experience.

The moon then moves on to its new cycle and begins to wax in the early evening sky.

Pay attention as the moon passes the planet Mercury and the star Spica in Virgo on Sept. 9.

There is a nice conjunction of the moon and Venus on the evening of Sept. 10, low in the west-northwest sky at sunset.

First quarter moon on the night of Sept. 13. This is a great time to view the many crates and deep shadows that appear on the lunar terminator. This is best viewed with binoculars and a telescope.

From here, the moon shows its gibbous or egg-shaped phase just before one of the most famous full moon events of the year.

I refer to the harvest moon, which will appear in our Arizona skies on the evening of Sept. 20.

This is the full moon that is closest to the autumnal equinox, which occurs that day at 12:20 p.m. Arizona time.

Here is some history on the wonders of the harvest moon.

On the evening of Sept. 20, get set for a spectacular moon rising just a few degrees to the right of due east, at 6:44 p.m. Arizona time.

This will be one memorable event to view, as the magic of the harvest moon, is both romantic and visually impressive too.

From here, the moon will wane and then move on to the last quarter on the 28th.

Enjoy the views of the moon, a small object only 2,159 miles in diameter and so much a part of our lives, both in a scientific way and a magical way.

There will be some great observations of the major planets in September too.

Let’s begin with Mercury, low in the west-northwest at sunset, best on the 14th as Mercury will be at an elongation of 27 degrees from the sun. Easy to see with the naked eye too.

Just to the left of Mercury is the brightest of the planets, Venus.

Venus shines with great intensity and that is due to the reflectivity of the Venusian clouds.

Wait about 30 minutes and look to the southeastern sky. This is the location of the giant planets Jupiter and Saturn. Jupiter shines brightest at nearly 400 million miles from Earth, while Saturn, a bit fainter, is some 845 million miles from Earth.

Both objects make for great views in the telescope.

Locate the position of Jupiter’s four main moons here.

September begins the journey to cooler weather and the tranquility of clear skies!

To print your own monthly star chart, click here.

To view satellites/dates/times of passage, click here.

Listen to the Dr. Sky Show on KTAR News 92.3 FM every Saturday at 3 a.m.

Podcasts are available here.