When we think about the night sky, most people likely picture constellations, planets, the moon, or even meteors, on occasion. But the third-brightest object in the sky doesn’t fall into any of those categories. Plus, it’s constantly moving. If you guessed that it’s the International Space Station (ISS), you’d be right (or just paid attention to the photo at the top of the post.
The ISS is visible to the naked eye, and looks like a plane that’s moving extra fast. But your chances of seeing it aren’t the same every night. Some nights—like tonight, and tomorrow night—the ISS will be at a height that’ll make it easier to see. Here’s what to know about finding the ISS this weekend (and anytime, really).
How to spot the International Space Station
Technically, the ISS is visible pretty frequently. But what makes this weekend special is that in many places, it’ll reach an elevation that will make it easier to see than usual.
Not sure when or where to look for information on how to spot the ISS? That’s what NASA’s Spot the Station website is for. On the home page, there’s an interactive map you can play around with, or just enter your city or town in the search bar, and you’ll be directed to your area.
If there are multiple points of visibility, pick the one closest to where you live, click on it, and it’ll bring up a chart that contains the times and other pieces of information for a roughly two-week period.
It’ll look like this:
The key here is “max height,” so as you can see, the ISS will be most visible tonight and tomorrow night in this area (which is Queens, NY). Your best bet for catching the ISS is when it’s above 40 degrees (max height—not temperature).
There are all kinds of numbers on the chart, but NASA breaks it all down for us:
Time is when the sighting opportunity will begin in your local time zone. All sightings will occur within a few hours before or after sunrise or sunset. This is the optimum viewing period as the sun reflects off the space station and contrasts against the darker sky.
Visible is the maximum time period the space station is visible before crossing back below the horizon.
Max Height is measured in degrees (also known as elevation). It represents the height of the space station from the horizon in the night sky. The horizon is at zero degrees, and directly overhead is ninety degrees. If you hold your fist at arm’s length and place your fist resting on the horizon, the top will be about 10 degrees.
Appears is the location in the sky where the station will be visible first. This value, like maximum height, also is measured in degrees from the horizon. The letters represent compass directions — N is north, WNW is west by northwest, and so on.
Disappears represents where in the night sky the International Space Station will leave your field of view.
The good news is that if you miss the ISS, it’ll always come circling back. You also have the option of signing up for alerts from NASA. They only send them on days when the height will be at least 40 degrees.