Must what goes up always come down? Sadia, via email
Send new questions to nq@theguardian.com.
Readers reply
I like Douglas Adams’ idea of flying: to throw yourself at the ground and miss. LMCollis
Yes. Although sometimes it can be: fall back to ground and miss, which we call “being in orbit”. HaveYouFedTheFish
Hopeful that Reform’s poll ratings do not defy this rule and come down very soon. On the other hand, Farage’s levels of hypocrisy show no signs of stopping their ascent. MosesQuest
If they can maintain orbital velocity or achieve escape velocity, they will not come down. Paulo777
That’s what the Venusians said about the asteroid that wiped out the dinosaurs. They just meant, “It won’t come down on Venus,” forgetting that there are other, more important planets around. jno50
Skylab was launched in May 1973 and spread itself over western Australia after “de-orbiting” in July 1979. MosesQuest
No orbit lasts for ever. In low orbit, usually the satellite slows due to atmospheric friction and tidal forces, and the orbit decays till it re-enters. In high orbit (usually geosynchronous), the same gravitational tidal forces are a bit more unpredictable and the orbit can decay, or occasionally the satellite may be ejected into a coincidental orbit around the sun instead. HaveYouFedTheFish
I seriously doubt if I’ll ever become fed down with the whole bloody lot of it. Eddie Chorepost
Amar Bharati has kept his right arm raised for 50 years. I think he would find it difficult to lower it now. GrasmereGardens
My football team always has. But maybe they’ll prove this wrong before I die. minermackem
Once the price of groceries goes up, they tend not to come down. Sagarmatha1953
