Astronomy explained with real measurements, each article linked to a part of the simulator you can try yourself.
Proxima Centauri is 4.24 light-years away. At Voyager 1's speed the trip would take about 75,000 years; at the speed of light, 4.24 years. Here is every option in between.
See every option → · Try the interactive Cosmic Journey
The total solar eclipse of 2 August 2027 crosses southern Spain, North Africa and the Middle East, with over 6 minutes of totality near Luxor. Where, when and how to watch.
Read the full guide → · Try the interactive Sky calendar
On 18 November 2026 Voyager 1 becomes the first human-made object one light-day from Earth: 25.9 billion km away, its signal taking a full day to reach us.
Read the full story → · Try the interactive Now & Here live tracker
A step-by-step guide to the transit method: read a TESS light curve, find repeating dips, fold them, and rule out eclipsing binaries, using real NASA data.
Read the full guide → · Try the interactive Planet Hunter
A practical beginner's guide to the night sky: the Moon's phases, the five naked-eye planets, how to tell a planet from a star, meteor showers, the ISS and when to look.
Read the full beginner's guide → · Try the interactive Now & Here
What you would really feel falling into a black hole: spaghettification near small ones, a gentle crossing at Sagittarius A*, and 28 seconds to the singularity.
Read the full guide → · Try the interactive Fall into a Black Hole simulator
Why the ISS is only visible around dawn and dusk, how bright it gets, how long a pass lasts, how to predict one for your location and how to tell it from planes and Starlink.
Read the full ISS spotting guide → · Try the interactive Now & Here
How big is the Sun next to other stars? Compare real measured sizes, from Earth-sized white dwarfs to supergiants like Betelgeuse and VY Canis Majoris.
Read the full star size comparison guide → · Try the interactive 3D Star Size Comparison Tool