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Tour quiz · From the ISS to the edge of the universe

What stuck?

Optional: 6 questions, one from each stop — a few minutes. Trying to remember is what makes it stick, so guess before you look back.

1 · Mission clocks

Why do GPS satellite clocks run fast overall, while ISS clocks run slow?

2 · Talking to Mars

Why can't you hold a live conversation with someone on Mars?

3 · The 1 g voyage

How can a crew reach the galaxy's centre in about 20 years of their own time?

4 · Expanding universe

If every galaxy sees the others moving away, where is the centre of the expansion?

5 · Cosmic horizons

Why can a signal we send today never reach some galaxies we can see?

6 · Cosmic timeline

On the app's powers-of-ten timeline, from the Planck time to the last black hole, where is today?

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