Question 1

How far is Mars from Earth right now?

Accepted Answer

Right now Mars is about 210.4 million km (1.406 AU) from Earth — roughly 11.7 light-minutes away at the speed of light. This distance changes constantly as both planets orbit the Sun (from about 55 to 400 million km).

Question 2

Why do planet distances keep changing?

Accepted Answer

Every planet orbits the Sun at a different speed and distance, so the gap between Earth and another planet is always changing. Planets are closest at "opposition" (when Earth is between the planet and the Sun) and farthest at "conjunction".

Question 3

What is an AU (astronomical unit)?

Accepted Answer

One astronomical unit (AU) is the average distance from Earth to the Sun — about 149.6 million km. Distances across the Solar System are often given in AU.

Body	Distance (km)	AU	Light-time
🌙 The Moon	0.38M	0.003	1 light-seconds
☿️ Mercury	100.71M	0.673	5.6 light-minutes
♀️ Venus	43.03M	0.288	2.4 light-minutes
🔴 Mars	210.36M	1.406	11.7 light-minutes
🟠 Jupiter	815.46M	5.451	45.3 light-minutes
🪐 Saturn	1282.81M	8.575	71.3 light-minutes
🔵 Uranus	2770.10M	18.517	2.6 light-hours
🔷 Neptune	4354.41M	29.107	4.0 light-hours