Where the International Space Station is right now

Russian cosmonaut Alexey Ovchinin
A Russian astronaut, a member of the International Space Station expedition 59/60, attends his final exam at a training center in Moscow. (Photo: STR/AFP/Getty Images)

The International Space Station (ISS) orbits Earth about every 90 minutes. This tracker, maintained by NASA, can tell you exactly when and where to look up if you want to see it streak by.

What to watch: The Spot the Station tool lets you put in your city or address to find out when you need to head outside to see the ISS fly past. The orbiting laboratory looks like a bright, unblinking plane when passing overhead.

How to tell if an exoplanet is habitable

 An exoplanet (the red spot) orbiting the brown dwarf
This composite image shows an exoplanet (the red spot) orbiting the brown dwarf 2M1207. This is the first exoplanet directly imaged. Image: ESO/Chauvin et al.

Figuring out whether a planet is habitable will take more than just understanding its orbit. According to a new study in the journal Science, scientists will also need to study a world’s atmosphere, magnetic field and even geological composition in order to really know if it’s capable of hosting life.

The big picture: Researchers have been hunting for habitable exoplanets using space and ground-based telescopes for years, but assessing whether a world can support life or not is difficult.