Orpington Astronomical Society

Astronomy => Alerts! Questions? Discussions... => Topic started by: spendrey on May 05, 2004, 19:34:00

Title: Stationery Jupiter?
Post by: spendrey on May 05, 2004, 19:34:00
I subscribe to a daily astronomical events update from thenakedsky.com. Today's one however left me a bit confused, it says:

The following events are scheduled for today, 5/5:

1) 9:00 AM Jupiter is stationery

What does it mean by Jupiter being stationery?
Title: Stationery Jupiter?
Post by: Rick on May 05, 2004, 19:49:00
It means that, as seen from the Earth, Jupiter will appear not to move against the background stars. It happens when the apparent motion of Jupiter against the background stars caused by the Earth's movement through space and the actual motion of Jupiter cancel out. Briefly. Very shortly the effects of one will overtake the effects of the other.
Title: Stationery Jupiter?
Post by: spendrey on May 05, 2004, 20:03:00
Is that similar to when we see the retrograde motion of Mars when the earth's orbit 'laps' it and it's motion appears to go backwards across the sky?
Title: Stationery Jupiter?
Post by: Rick on May 05, 2004, 21:14:00
Exactly. Well, the principle's the same. The actual numbers are different...

[ This Message was edited by: Rick on 2004-05-05 13:15 ]
Title: Stationery Jupiter?
Post by: Ian on May 06, 2004, 17:48:00
I thought you meant that Jupiter is comprised of envelopes, writing paper and bic biros? :wink:
Title: Stationery Jupiter?
Post by: Rocket Pooch on May 06, 2004, 19:43:00
did you know there's a planet where all the lost biro's go to live.  I wonder if its near Jupiter?
Title: Stationery Jupiter?
Post by: Ian on May 06, 2004, 22:02:00
is that the same place all the empty ones go. Although thinking about it, I don't think I've ever seen an empty one. Do they make ink out thin air when they're not being used?
Title: Stationery Jupiter?
Post by: Mike on May 06, 2004, 22:23:00
Empty biros are eaten by baby pigeons.