Five Planets Visible to the Naked Eye in Rare Astronomical Event

This illustration shows the pre-dawn view expected for Feb. 1, when astronomers say Mercury will be most visible. (Courtesy of Sky & Telescope)

For the next month or so, five planets will be visible to the naked eye at the same time. The last time this celestial show took place was over a decade ago.

Thanks to our sponsors:

View all sponsors

According to Sky and Telescope Magazine, if you wake up 45 minutes before sunrise and look southeast, in the general direction of an unobstructed sunrise, you’ll see five planets sans telescope: Mercury, Venus, Mars, Jupiter and Saturn. The sun rises around 7 a.m. this time of year, so stargazers are encouraged to head out around 6:15 a.m.

While Mercury is the closest of the five planets to Earth, it will be the hardest to see due to its low location close to the horizon. Mercury is most visible this week and next; after Feb. 6, it will be difficult to observe. As the brightest planet in the solar system, Venus will be the easiest to spot by a long shot. The bright stars Antares and Spica will also be visible.

[Never miss a "Chicago Tonight" headline! Get our daily newsletter delivered straight to your inbox.]

The five planets will appear aligned on an arc, although that’s not truly the case. Instead, they’re simultaneously positioned on the same side of the Sun and visible from Earth. All planets orbit on roughly the same plane, called the ecliptic, but since they orbit the Sun at different speeds, this configuration doesn’t happen often. For instance, Mercury takes 88 days to travel around the Sun while Saturn takes 29 years!

This diagram shows the locations of the planets and their orbits. Circular symbols denote the planets' expected locations on Feb. 1 and arrows indicate how far they'll travel in a month's time. The outer planets don't change position enough to notice on this scale. (Courtesy of Sky & Telescope)

So how can you be sure what you’re seeing are planets?

As a general rule of thumb, Adler Planetarium astronomer Michelle Nichols says stars twinkle and planets don’t.

She also says a common vexation for urban astronomers is actually a blessing in disguise in this rare scenario.

Chicago is no stranger to light pollution; the glow of the city lights obscures our view of the Milky Way and its stars. Nichols believes the absence of visible stars makes it easier for Chicagoans to distinguish planets.

“When people are just learning the sky,” Nichols says, “I actually recommend they do it in a city environment like Chicago first because the light pollution blocks out all the dimmer stars.

“If you go out where it’s really dark, the sky can be very confusing because you have a whole lot more stars to pay attention to and things are harder to find.”

The last time all five of these planets were visible to the naked eye was from late December 2004 to January 2005. Nichols says you won’t have to wait nearly that long or wake up early for the next occurrence: all five will be observable in the evening sky this August.

Follow Evan Garcia on Twitter: @EvanRGarcia

Thanks to our sponsors:

View all sponsors

Thanks to our sponsors:

View all sponsors