The Briefing Room

General Category => Science, Technology and Knowledge => Space => Topic started by: Elderberry on December 09, 2018, 12:51:03 am

Title: A Big Hole in the Sun’s Atmosphere
Post by: Elderberry on December 09, 2018, 12:51:03 am
Spaceweather December 7, 2018   

A large hole in the sun’s atmosphere is facing Earth and spewing a stream of solar wind in our direction. NASA’s Solar Dynamics Observatory is monitoring the structure, shown here in a false-color UV image taken on Dec. 6th:

(https://i1.wp.com/spaceweather.com/images2018/06dec18/ch_strip.jpg)

The hole (technical term: “coronal hole”) is so large it almost completely bisects the solar disk, stretching more than a million km across the sun’s equator.

More: https://spaceweatherarchive.com/2018/12/07/a-big-hole-in-the-suns-atmosphere/ (https://spaceweatherarchive.com/2018/12/07/a-big-hole-in-the-suns-atmosphere/)
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Skeptic on December 10, 2018, 12:58:40 am
I would call that a depression because it really isn't a hole. Intriguing. They say there's a sunspot minimum but what do you call that? A large sunspot.
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Wingnut on December 10, 2018, 01:00:48 am
I think we can rule out man made causes.
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Elderberry on December 10, 2018, 02:04:00 am
I would call that a depression because it really isn't a hole. Intriguing. They say there's a sunspot minimum but what do you call that? A large sunspot.

A depression is still a hole. A shallow hole.

Coronal holes are areas where the Sun's corona is colder, hence darker, and has lower-density plasma than average because there is lower energy and gas levels.

Sunspots are active regions on the sun's surface. These are the areas of tightly packed magnetic fields of opposing polarity. They build-up high energy and released at certain condition.
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Skeptic on December 10, 2018, 07:56:47 am
A depression is still a hole. A shallow hole.

Coronal holes are areas where the Sun's corona is colder, hence darker, and has lower-density plasma than average because there is lower energy and gas levels.

Sunspots are active regions on the sun's surface. These are the areas of tightly packed magnetic fields of opposing polarity. They build-up high energy and released at certain condition.

I don't want to get on with what defines a hole, especially with a female, but I think that a hole is deeper than it is wide and usually defined as circular.

True about the sunspots thing.
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: DB on December 10, 2018, 10:51:21 am
A depression is still a hole. A shallow hole.

Coronal holes are areas where the Sun's corona is colder, hence darker, and has lower-density plasma than average because there is lower energy and gas levels.

Sunspots are active regions on the sun's surface. These are the areas of tightly packed magnetic fields of opposing polarity. They build-up high energy and released at certain condition.

So you're saying coronal holes generally occur when sunspot activity is low?
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Elderberry on December 10, 2018, 08:58:39 pm
I don't want to get on with what defines a hole, especially with a female, but I think that a hole is deeper than it is wide and usually defined as circular.

You think too much.

Partial Definition of hole in English:

1.A hollow place in a solid body or surface.

1.1 An aperture passing through something.

2. A place or position that needs to be filled because someone or something is no longer there.

3. (informal) An unpleasant place.
Title: Re: A Big Hole in the Sun’s Atmosphere
Post by: Elderberry on December 10, 2018, 09:04:09 pm
So you're saying coronal holes generally occur when sunspot activity is low?

That's my guess.

Quote
Such holes may appear at any time of the solar cycle but they are most common during the declining phase of the cycle. Coronal holes occur when the Sun's magnetic field is open to interplanetary space.