Observe the planets One of the most stunning ways to witness the magic of the night sky, there is no better way to view the night sky than with the alignment of the planets. This is where multiple planets line up next to each other.
On January 21, six planets—Venus, Mars, Jupiter, Saturn, Uranus and Neptune—will appear simultaneously in the sky, and their alignment will be easily visible from nearly anywhere around the globe. But if you missed your chance to observe the night sky on January 21, don't worry: There's plenty of time to watch this parade of planets.
This alignment will last about a month, until mid-to-late February. However, the positions of the planets will change during this time, so their positions on January 21st will not be the same as in late February.
While conjunctions of two planets are somewhat common, conjunctions of five or more planets are quite rare. There will be two more planetary alignments of five or more planets this year, but after that, the next one of five or more planets won't happen until 2040.
Here's everything you need to know about understanding planetary alignments.
For optimal vision, allow your eyes to adjust to the dark for 20 to 30 minutes. You'll want to see this planetary alignment after the sun has set, away from artificial light, which makes it difficult to see objects in the night sky.
Mars, Jupiter, Uranus, Neptune, Saturn and Venus will appear in an arc from east to west. You can spot four of the planets with the naked eye; however, two of them, Uranus and Neptune, require a good pair of high-powered binoculars or a backyard telescope. Here's an overview of exactly where to look for each planet in the night sky on the 21st, but if you're not sure how to find them, don't worry - apps like Stellarium can help you locate planets and other celestial objects easily.
The best time to view the planets is shortly after sunset, as three of them - Venus, Saturn and Neptune - appear around 9 to 10:30 pm local time. Note that the exact times each planet rises and sets will vary slightly depending on where you are on Earth; you can use a website like Time and Date to find the exact times for your location.
It's best to start observing the sky earlier in the evening if you can, as Venus, Saturn and Neptune will move lower to the horizon before setting, so they will become increasingly difficult to observe as the night goes on.
On January 21, Mars is in the east, directly beneath the constellation Gemini. Mars is just at opposition, which means Earth is between it and the Sun, so the Red Planet will appear at its largest and brightest and will be visible all night long.
Mars is easy to see with the naked eye. But if you use a backyard telescope, you'll be able to see the Arctic ice cap that spans more than 600 miles, as well as Valles Marineris, the largest canyon in the solar system, which stretches along the Martian equator and ends 1,800 miles long.
Jupiter will be in the constellation Taurus, west of Mars. Jupiter is easy to see with the naked eye. However, a pair of high-powered binoculars will allow you to see Jupiter's moons and maybe even its cloud bands.
A backyard telescope allows you to see this giant planet in greater detail. Look for Jupiter's cloud bands and the stunning Red Spot, an anticyclone more than 10,000 miles wide (1.3 times the width of Earth). The Red Spot is not always visible from Earth because Jupiter's days are about 10 hours long, which means the storm faces away from Earth for a significant portion of many nights. You can use Sky & Telescope's calculator to see when it will be visible from your location.
Jupiter is visible most of the night: it rises in the mid-to-late afternoon of January 21 and sets around 3 to 5 a.m. on January 22, depending on your exact location .
On the 21st, Uranus will be about 50 degrees west of Jupiter and slightly lower than Jupiter. Uranus will appear near the Pleiades, a bright star cluster visible to the naked eye.
You'll need a pair of high-powered binoculars or a backyard telescope to see Uranus, as it's too dim to be easily seen with the naked eye. With such a device, Uranus looks like a pale blue star. Although Uranus has rings, they are too faint to be seen even with observation equipment. However, if you have a powerful backyard telescope, you might be able to see its moons.