Astronomy Picture of the Day 8-05-02

NASA ^ | 8-05-02 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2002 August 5

Rays from an Unexpected Aurora
Credit & Copyright: Lyndon Anderson (Prairie Journal)

Explanation: This aurora was a bit of a surprise. For starters, last Friday morning, no intense auroral activity was expected at all. Possibly more surprising, however, the aurora appeared to show an usual structure of green rays from some locations. In the above image, captured from North Dakota, USA, a picket fence of green rays stretches toward the horizon. Mirroring the green rays is a red band, somewhat rare in its own right. Lights from the cities of Bismarck and Mandan are visible near the horizon. Large sunspot groups indicate that activity from the currently active Sun is relatively likely, possibly causing other streams of energetic particles to cascade onto the Earth and so causing more auroras.

[petuniasevan]

Aurorae occur on other planets with magnetic fields. Jupiter's have been photographed!

Hubble Image
October 17, 1996
Photo No.: STScI-PRC96-32

The green oval and its dot show the position of Io and its effect ("flux tube": current of charged particles)
on Jupiter's aurorae.

AARRRGGGHHH!!! I was MONITORING my STD Aurora Monitor program and Spaceweather both!
This was unexpected, and I MISSED IT!

DANG! It's beautiful, though.
Did anyone see it? Get photos?

Get on the APOD PING list!

[petuniasevan]

APOD PING!

[petuniasevan]

Gotta post-and-run.
I'm on day shift this week and won't post the APOD again until Tuesday afternoon, most likely.

[RightWhale]

Still too light here to see much aurora. The red aurora is rare, but there was a huge red aurora when the first Space Shuttle was launched. The green rays are common, and when they are bright and focused they also move rapidly like a flapping curtain or swirl across the sky, often with other colors in the most intense portions.

[MozartLover]

bump

[Graewoulf]

The active link "other streams" in the above official explanation discusses anti-auroras.

In your humble, but always correct opinion, are the dark "pickets" between the "green pickets" anti-auroras?

If so, then the "picket fence" appearance is more likely due to the effect of the Earth's Magnetic field upon the incoming solar wind, rather than discrete pulses from the Sun.

[RightWhale]

dark "pickets" between the "green pickets" anti-auroras?

The spaces between the bright features are just more aurora. The aurora moves, the brighter the faster. There is another aurora at the opposite pole of earth that is very similar at the same time to Aurora Borealis and can be seen from NZ and Australia.

[BossyRoofer]

Awsome!

[sleavelessinseattle]

WOW...I blinked and now have THREE APODS to go through...Time is relative but it FLIES like a Tachyon!
Here is an older APOD Christine!

[christine]

replied to your mail before i saw this. thanks! now i know what an apod is! ;)