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Late September-October planet guide

Use the moon to catch Mercury before dawn in late September, 2016. Then watch as Jupiter pairs with Mercury in the picturesque glow of dawn on October 11.

Skywatcher, by Predrag Agatonovic.

Skywatcher, by Predrag Agatonovic.

From around the world, three of the five bright planets appear in the evening sky as darkness falls in late September and October 2016: Venus, Saturn and Mars. One other bright planet – Mercury – appears before dawn. Mercury is near the sunrise point and most easily seen from the Northern Hemisphere. Mercury soars highest up from the glare of sunrise in late September 2016. Before Mercury disappears in the sun’s glare in October, the very bright planet Jupiter will climb away from the sunrise glare and appear right next to Mercury before dawn. Watch for the moon to sweep past Mercury in late September, then keep watching as Jupiter meets up with Mercury on October 11. Just know that – even from Northern Hemisphere locations, where the view is best – you’ll need to look only shortly before sunrise. Follow the links below to learn more about planets in late September and October, 2016.

All you need to know: September equinox

Mercury before dawn late September and early October

Bright Jupiter emerges before dawn in early October

Brilliant Venus sets at dusk or early evening

Mars, east of Saturn, dusk until mid-to-late evening

Saturn, west of Mars, dusk until early-to-mid evening

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The bow of the waning crescent moon points toward Mercury's place over the sunrise point on the horizon. Mercury is more easily viewed in the Northern Hemisphere. Read more.

The bow of the waning crescent moon points toward Mercury’s place over the sunrise point on the mornings of September 27 and 28. On September 29, the moon is right next to Mercury. This planet is most easily viewed in the Northern Hemisphere. Read more.

Mercury before dawn late September and early October. Mercury swings to its greatest morning elongation from the sun on September 28, to present a fine morning apparition of Mercury in the Northern Hemisphere (and not as good for the Southern Hemisphere). Watch for Mercury above the sunrise point.

If you are blessed with clear predawn skies, watch for the conjunction of Mercury and Jupiter on the morning of October 11, 2016. See the sky chart above.

From northerly latitudes, Mercury should remain visible before sunrise for the first week or two of October 2016.

Click here for recommended almanacs; they can give you Mercury’s rising time in your sky.

How many of you will see Mercury and Jupiter snuggling up together before sunrise on or near October 11, 2016?

How many of you will see Mercury and Jupiter snuggling up together before sunrise on or near October 11, 2016?

Bright Jupiter emerges before dawn in early October. Officially, Jupiter passed into the morning sky during September, but you’re not likely to see it until early October, when it will appear near Mercury before dawn. The Northern Hemisphere has the best view of the conjunction of these two worlds on October 11.

From the northerly latitudes and the tropics, expect Jupiter to become visible before sunrise around the end of the first week of October. From temperate latitudes in the Southern Hemisphere, Jupiter might not be visible to the eye before sunrise until late October or November, but photographers and those with optical aid can try their luck!

Afterwards, as the October mornings pass, Mercury will become lost in the sun’s glare, but Jupiter will be climbing up and away from the sunrise.

If you are blessed with an unobstructed horizon in the direction of sunrise, watch the waning crescent moon with Jupiter on October 27 and October 28.

At that time, the moon and Jupiter – though still harder to see from southerly latitudes – may be visible to the eye the Southern Hemisphere. Have binoculars handy for sweeping near the sunrise horizon!

In late October, let the waning crescent moon be your guide to the giant planet Jupiter.

In late October, let the waning crescent moon be your guide to the giant planet Jupiter. Read more.

Starting around October 2, 2016, use the slim waxing crescent moon to find the planets Venus and Saturn. Read more.

Starting around October 2, 2016, use the slim waxing crescent moon to find the planets Venus and Saturn. Read more.

Brilliant Venus sets at dusk or early evening . People have been amazed at the brilliance of Venus in the west after sunset, in these past weeks. It’s the brightest planet and very, very bright, even though it’s been low in the sky.

Be sure to catch the waxing crescent moon near Venus for several evenings centered on or near October 3. See the chart above. Binoculars will enhance the view!

Venus will climb upward from the setting sun throughout the month, while the planet Saturn will fall downward. Look for the two to meet up after sunset in late October.

By the way, when Venus passed behind the sun in June, it passed directly behind it, as seen from Earth. That happened on June 6, 2016, and at that time Venus officially transitioned from our morning to our evening sky. Exactly four years previous to Venus’ passing directly behind the sun on June 6, 2016, Venus swung directly in front of the sun on June 6, 2012. You might remember that event: the widely watched transit of Venus, during which Venus crossed the sun’s face as seen from Earth (see photos). It was the last transit of Venus until December 11, 2117.

Venus and Mercury - and the star Regulus - are deep in evening twilight. This is Venus, caught from a plane over southern Oregon, on July 28, 2016. Photo by Gemini Brett.

Here’s Venus, caught from a plane over southern Oregon, on July 28, 2016, just as the planet was emerging into the evening twilight sky. Photo by Gemini Brett.

View larger | Mikhail Chubarets in the Ukraine made this chart.  It shows the view of Mars through a telescope in 2016.  We pass between Mars and the sun on May 22.  We won't see Mars as a disk like this with the eye alone. But, between the start of 2016 and May, the dot of light that is Mars will  grow dramatically brighter and redder in our night sky. Watch for it!

View larger | Mikhail Chubarets in the Ukraine made this chart. It shows the view of Mars through a telescope in 2016. We never see Mars as a disk like this with the eye alone. But you can see why Mars was bright to the eye in 2016, and is now fading.

The moon, Mars and Saturn on October 8, 2016. Read more

The moon, Mars and Saturn on October 8, 2016. Read more.

Mars, east of Saturn, dusk until mid-to-late evening. Mars and Saturn start out October in the southwest sky at nightfall. Mars is still bright this month, though much fainter than it was earlier in 2016! Saturn came closest to Earth for the year on June 3, less than four days after Mars’ closest approach to Earth on May 30.

Although Mars and Saturn are fading, they’re bright and easy to see – and Mars ia a bit brighter than Saturn!

Look for Mars and Saturn near Antares, the brightest star in the constellation Scorpius the Scorpion. They make a noticeable triangle on the sky’s dome. Let the moon help guide your eye to Mars, Saturn and the bright star Antares for several evenings, centered on or near October 8.

Throughout October, watch for Mars to shift eastward of Saturn night by night, while Saturn and Antares sink westward, toward the setting sun. By November, Saturn and Antares will fade into the glare of sunset, but Mars will still shine in the November evening sky.

Looking for a sky almanac? EarthSky recommends…

Look for the waxing crescent moon near the planet Saturn (and the star Antares) on October 5 and 6. Read more.

Look for the waxing crescent moon near the planet Saturn (and the star Antares) on October 5 and 6. Read more.

Saturn, west of Mars, dusk until early-to-mid evening. Both Mars and Saturn are near Antares in the constellation Scorpius. Throughout October, Mars keeps moving farther east of Saturn, while Saturn edges closer to the sunset. Saturn (and Antares) will disappear from the evening sky sometime in November 2016, while Mars will remain a fixture of the evening sky for several more months.

Although Saturn appears respectably bright, its brilliance can’t match that of Mars. Look for Saturn near Mars, even though Mars moves farther away from Saturn (and the star Antares) all month long. These two worlds form a bright celestial triangle with the star Antares in the September night sky. Mars is brighter than Saturn, which in turn is brighter than Antares.

Saturn, the farthest world that you can easily view with the eye alone, appears golden in color. It shines with a steady light.

Binoculars don’t reveal Saturn’s gorgeous rings, by the way, although binoculars will enhance Saturn’s golden color. To see the rings, you need a small telescope. A telescope will also reveal one or more of Saturn’s many moons, most notably Titan.

Saturn’s rings are inclined at a little more than 26o from edge-on, exhibiting their northern face. Next year, in October 2017, the rings will open most widely, displaying a maximum inclination of 27o.

As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In the year 2025, the rings will appear edge-on as seen from Earth. After that, we’ll begin to see the south side of Saturn’s rings, to increase to a maximum inclination of 27o by May 2032.

Click here for recommended almanacs. They can help you know when the planets rise, transit and set in your sky

http://www.leisurelyscientist.com

Tom Wildoner over-exposed Saturn itself to capture this view of Saturn’s moons on June 25, 2016. Visit Tom at LeisurelyScientist.com.

Contrasting the size of Saturn and its rings with our planet Earth via Hubble Heritage Team.

Contrasting the size of Saturn and its rings with our planet Earth via Hubble Heritage Team.

What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.

From late January, and through mid-February, 5 bright planets were visible at once in the predawn sky. This image is from February 8, 2016.  It's by Eliot Herman in Tucson, Arizona.  View on Flickr.

From late January, and through mid-February, 5 bright planets were visible at once in the predawn sky. This image is from February 8, 2016. It’s by Eliot Herman in Tucson, Arizona. View on Flickr.

Bottom line: In late September and October 2016, three of the five bright planets appear in the evening sky as darkness falls: Venus, Saturn and Mars. Mercury is visible before dawn, and Jupiter will join Mercury in the dawn sky in early October.

Easily locate stars and constellations with EarthSky’s planisphere.

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Bruce McClure

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