Comments and questions about the
APOD on the main view screen.
-
APOD Robot
- Otto Posterman
- Posts: 4688
- Joined: Fri Dec 04, 2009 3:27 am
Post
by APOD Robot » Tue Apr 26, 2022 4:06 am
Planet Parade over Sydney Opera House
Explanation: The world is waking up to a picturesque planet parade. Just before dawn, the eastern skies over much of
planet Earth are decorated by a notable line of familiar planets. In much of Earth's northern hemisphere, this
line of planets appears most
nearly horizontal, but in much of
Earth's southern hemisphere, the line appears more nearly vertical.
Pictured over the
Sydney Opera House in southern
Australia, the planet line was captured nearly vertical about five days ago. From top to bottom, the morning planets are
Saturn,
Mars,
Venus, and
Jupiter. As April ends, the angular distance between
Venus and Jupiter will gradually pass below a degree as they switch places. Then, as May ends,
Jupiter will pass near Mars as those two planets
switch places. In June, the parade will briefly expand to include Mercury.
-
orin stepanek
- Plutopian
- Posts: 7610
- Joined: Wed Jul 27, 2005 3:41 pm
- Location: Nebraska
Post
by orin stepanek » Tue Apr 26, 2022 11:47 am
PlanetParadeSydney_Agrawal_960.jpg
From top to Opera house; Saturn; Mars; Venus; Jupiter!
Earth the bottom planet

Very nicely done!
https://ak.picdn.net/shutterstock/video ... humb/1.jpg
Url of dog & cat!
You do not have the required permissions to view the files attached to this post.
Orin
Smile today; tomorrow's another day!
-
MoonRockMan
- Ensign
- Posts: 14
- Joined: Tue Jan 04, 2022 5:39 pm
Post
by MoonRockMan » Tue Apr 26, 2022 5:06 pm
Why exactly is the line of planets mostly horizontal in the northern hemisphere but more vertical in the southern hemisphere?

-
bystander
- Apathetic Retiree
- Posts: 21027
- Joined: Mon Aug 28, 2006 2:06 pm
- Location: Oklahoma
Post
by bystander » Tue Apr 26, 2022 6:27 pm
MoonRockMan wrote: ↑Tue Apr 26, 2022 5:06 pm
Why exactly is the line of planets mostly horizontal in the northern hemisphere but more vertical in the southern hemisphere?
I wondered that myself, but I think it has to do with the difference between the Earth's equatorial plane and the ecliptic, the Earth's path around the Sun. (I say the ecliptic, but it's more likely the plane of the Solar system.)
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
-
Chris Peterson
- Abominable Snowman
- Posts: 16666
- Joined: Wed Jan 31, 2007 11:13 pm
- Location: Guffey, Colorado, USA
Post
by Chris Peterson » Tue Apr 26, 2022 7:06 pm
MoonRockMan wrote: ↑Tue Apr 26, 2022 5:06 pm
Why exactly is the line of planets mostly horizontal in the northern hemisphere but more vertical in the southern hemisphere? :)
The ecliptic sweeps across the sky over the course of the day. In Sydney, a bit before dawn, it passed almost straight overhead, so we see the planets vertical with respect to the eastern horizon. In New York the ecliptic is overhead now in the middle of the day, and the planets look vertical with respect to the western horizon. But since the Sun is up, we don't see them. The planets would be horizontal in Sydney in late morning.
-
MoonRockMan
- Ensign
- Posts: 14
- Joined: Tue Jan 04, 2022 5:39 pm
Post
by MoonRockMan » Tue Apr 26, 2022 7:23 pm
bystander wrote: ↑Tue Apr 26, 2022 6:27 pm
MoonRockMan wrote: ↑Tue Apr 26, 2022 5:06 pm
Why exactly is the line of planets mostly horizontal in the northern hemisphere but more vertical in the southern hemisphere?
I wondered that myself, but I think it has to do with the difference between the Earth's equatorial plane and the ecliptic, the Earth's path around the Sun. (I say the ecliptic, but it's more likely the plane of the Solar system.)
Chris Peterson wrote: ↑Tue Apr 26, 2022 7:06 pm
The ecliptic sweeps across the sky over the course of the day. In Sydney, a bit before dawn, it passed almost straight overhead, so we see the planets vertical with respect to the eastern horizon. In New York the ecliptic is overhead now in the middle of the day, and the planets look vertical with respect to the western horizon. But since the Sun is up, we don't see them. The planets would be horizontal in Sydney in late morning.
Thank you so much!