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Guide to the Stars: Northern Hemisphere, Latitudes 30' to 60' North

Sky and Telescope's Pocket Sky Atlas

Collins Star Finder Pack

Binocular Highlights: 96 Celestial Sights for Binocular Users

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Previous:
The Moon

Next:
Asteroids, Comets, and Meteors

The Planets

Planets are often the brightest objects in the sky and are easy to identify because, unlike stars, they don’t twinkle. All planets orbit the Sun, and all their orbits lie within the same plane—which means that all planets more or less follow the same path in the sky, close to the ecliptic. Some planets, such as Mars, seem to move backward along the ecliptic at certain times, a phenomenon called retrograde motion.

If you see a bright object far from the ecliptic (near the constellation Cassiopeia, for example), it’s definitely not a planet. To learn which planets are visible on a given night, use a planet-finding chart or ephemeris (see Stargazing Tools).

Mercury

Mercury has a heavily cratered surface like the Moon, but you won’t be able to see it clearly—it just looks like a bright dot.

Where it is: Closest to the Sun. The farthest Mercury ever gets from the Sun is 28°, so you can view it only during twilight, right after sunset or right before sunrise, barely above the horizon.
What you need to see it: Under good conditions you can spot Mercury with the naked eye, but usually you’ll need a telescope. Make sure there are no obstacles blocking the horizon in the direction of the Sun.

Venus

Venus is often the brightest object in the sky—it emits a glowing, bluish-green light. Its atmosphere is so thick that you can’t see its surface, even with a telescope.

Where it is: Closer to the Sun than the Earth. Venus is sometimes called the Morning Star or Evening Star because it stays relatively close to the Sun, and you can see it at dawn or dusk.
What you need to see it: You don’t need anything to spot Venus—not even dark skies. Venus is one of the few objects (besides the Sun and the Moon) that you can spot before the Sun has set or after it has risen.

Mars

Mars looks like a bright red dot, and through a telescope you can spot its white polar caps and some of its distinct, dark surface markings.

Where it is: The next planet out from the Earth and, about every 26 months, the closest one to us.
What you need to see it: It’s easy to spot Mars with the naked eye by its orange-red color, but the planet is best observed through a small telescope.

Jupiter

Jupiter is far from the Earth, but its colossal size makes it very bright. You can spot its larger moons all in a line, and if you observe several nights in a row, you’ll notice how the moons move with respect to the planet. Jupiter has a striped appearance due to its cloud belts, which have spots and irregularities—you can watch them rotate with Jupiter over the course of a night (Jupiter rotates once every 10 hours or so).

Where it is: Jupiter takes 12 years to make one orbit around the Sun, so its location in relation to the stars will be roughly the same over a year’s time. Just look up its current location in a planet-finding chart.
What you need to see it: You can find Jupiter easily with the naked eye, and you see up to four of its largest moons simply with a good pair of binoculars. A small telescope is best for viewing Jupiter’s atmospheric features, including the Great Red Spot (a giant swirling storm system).

Saturn

Saturn is a favorite among stargazers because of its rings. At different times of the year, you can catch the rings faint and close to edge-on, but most times they are brighter and more face-on. Even with a large telescope, you won’t be able to see structures within the rings. Saturn’s surface is covered by cloud belts, but less prominently than Jupiter’s.

Where it is: Saturn is farther out than Jupiter and also has a very long orbital period (almost 30 years).
What you need to see it: Saturn is bright to the naked eye, but you’ll need a small telescope to see its rings.

Uranus

Uranus is faint, with cloudlike belts similar to Jupiter’s and Saturn’s. These belts are usually only visible with large, professional telescopes, though.

Where it is: Very far from the Sun (19 times farther than the Earth).
What you need to see it: You’ll need binoculars to find Uranus among the stars, and a professional telescope to see its atmosphere. A modest telescope will reveal its pale, greenish sphere.

Neptune

Neptune is very faint and looks featureless, except through the largest professional telescopes.

Where it is: Very far from the Sun (30 times farther than the Earth).
What you need to see it: You’ll need a small telescope to see Neptune at all. A modest-sized telescope will reveal it as a pale, bluish dot.

Pluto

Even viewed through the Hubble Space Telescope, Pluto doesn’t look like much more than a bright dot. In 2006, the International Astronomical Union “demoted” Pluto from full planet status—it is now officially classified as a dwarf planet, though astronomers continue to debate its status.