Space Time
What's up tonight
Is it worth going out tonight? Space Time gives your sky a clear-sky verdict, then shows what's up: which planets are visible, the Moon phase, the best deep-sky targets, and when the ISS flies over. A free 3D sky map and observing planner that runs in your browser.
🚀 Open the sky map Free · No account · Set your location and go
Is it worth going out tonight?
Before you haul the scope out, Space Time gives your location a clear-sky verdict: a 0 to 100 score from the real forecast, weighing cloud cover, the jet stream (your seeing), transparency, rain, the Moon and your light pollution (estimated automatically from your location, with a manual override). The night is broken down hour by hour so you can see exactly when it clears, with the usable hours and your longest unbroken run called out. A seven-night outlook ranks the whole week, so you can pick the best evening instead of gambling on tonight.
Tonight's Best, ranked for your location
Set your latitude and longitude and the planner scores every visible target by how high it climbs, how bright it is, and how badly the Moon will wash it out. That covers the Moon itself, the planets, and 207 deep-sky objects. What you get back is an ordered list of the best things to point at tonight, with rise, transit and set times in your local time.
Where the planets are right now
Every planet is placed with the astronomy-engine library, built on JPL ephemeris data, so Venus, Mars, Jupiter and Saturn show up where they actually are in your sky, to within about an arcsecond. Drop into the first-person planetarium view to see them against the constellations. Or stay in space and watch the same geometry from outside.
Catch the ISS & satellites
Pass predictions for the International Space Station, Tiangong and Hubble come from real two-line-element data run through the SGP4 propagator. You'll know when to step outside and which way to face.
FAQ
Will it be clear enough to observe tonight?
Space Time scores your sky from the real weather forecast: a 0 to 100 verdict weighing cloud, seeing (the jet stream), transparency, rain, the Moon and your light pollution, hour by hour, with the usable hours flagged. A seven-night outlook helps you pick the best evening.
What planets are visible tonight?
Set your location and open the observing planner or planetarium view. It shows which planets and the Moon are up, how high they get, and their rise/transit/set times for your date and place.
How do I find what's up from my location?
Enter your latitude/longitude or pick a city. The "Tonight's Best" planner ranks the planets, Moon and 207 deep-sky objects by altitude, brightness and Moon interference.
When can I see the ISS?
Space Time predicts visible ISS, Tiangong and Hubble passes from real TLE data with SGP4. Pick a pass and the clock jumps to it.
Is it free?
Yes. In your browser, no account, no download.