Starship Asterisk*

A Triangular Prominence Hovers Over the Sun

Explanation: Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence. Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months. A prominence glows brightly because it contains particularly hot, dense, or opaque solar plasma. The surprising triangular structure occurred last week. Larger than our Earth, the iconic prominence was imaged by several solar photographers and documented by NASA's Solar Dynamic Observatory to form and violently dissipate in about a day. The featured image was captured in a color of red light emitted strongly by hydrogen. Below, solar fibrils carpet the Sun's chromosphere, while the background sky is so faint in comparison that no stars are visible. Our Sun's surface has been quite active this year.

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The "documented by NASA" link to the SDO movie that this clip was apparently processed from shows this (after rotating and flipping to match the APOD):


So, ignoring the intense heat that close to the Sun, if the Earth were embedded in this prominence, what would happen to the atmosphere?

johnnydeep wrote: ↑Mon Sep 02, 2024 1:17 pm The "documented by NASA" link to the SDO movie that this clip was apparently processed from shows this (after rotating and flipping to match the APOD):


traingular prominence on sun from SDO.jpg


So, ignoring the intense heat that close to the Sun, if the Earth were embedded in this prominence, what would happen to the atmosphere?

Well, start by considering the density. The density of a prominence is about the same as the density of Earth's atmosphere somewhere between 30 and 50 kilometers above the surface. (The pressure at that height is a fraction of a percent of the surface pressure. Not a hard vacuum, but pretty thin.)

This type of triangular structure, drawn several times next to a circle, is exactly how I would draw the sun as a child, along with fellow untold millions of children drawing the sun like this! We were right all along haha!

Chris Peterson wrote: ↑Mon Sep 02, 2024 1:33 pm

johnnydeep wrote: ↑Mon Sep 02, 2024 1:17 pm The "documented by NASA" link to the SDO movie that this clip was apparently processed from shows this (after rotating and flipping to match the APOD):


traingular prominence on sun from SDO.jpg


So, ignoring the intense heat that close to the Sun, if the Earth were embedded in this prominence, what would happen to the atmosphere?

Well, start by considering the density. The density of a prominence is about the same as the density of Earth's atmosphere somewhere between 30 and 50 kilometers above the surface. (The pressure at that height is a fraction of a percent of the surface pressure. Not a hard vacuum, but pretty thin.)

So, then, not much would happen? At what point - if any - does the temperature of a very rarefied plasma become an issue?

johnnydeep wrote: ↑Mon Sep 02, 2024 3:37 pm

Chris Peterson wrote: ↑Mon Sep 02, 2024 1:33 pm

johnnydeep wrote: ↑Mon Sep 02, 2024 1:17 pm The "documented by NASA" link to the SDO movie that this clip was apparently processed from shows this (after rotating and flipping to match the APOD):


traingular prominence on sun from SDO.jpg


So, ignoring the intense heat that close to the Sun, if the Earth were embedded in this prominence, what would happen to the atmosphere?

Well, start by considering the density. The density of a prominence is about the same as the density of Earth's atmosphere somewhere between 30 and 50 kilometers above the surface. (The pressure at that height is a fraction of a percent of the surface pressure. Not a hard vacuum, but pretty thin.)

So, then, not much would happen? At what point - if any - does the temperature of a very rarefied plasma become an issue?

Temperature isn't really the issue. Prominences aren't that much hotter than the upper atmosphere as it is. What matters is how much energy can be delivered, and if you don't have many atoms, you can't transfer much energy. (That's how a Thermos works.)

I think the impact on our atmosphere depends on other factors, such as the velocity of the flow around us, and what magnetic fields are doing.

Sure glad we are 93 million miles from that activity!

Chris Peterson wrote: ↑Mon Sep 02, 2024 3:40 pm

johnnydeep wrote: ↑Mon Sep 02, 2024 3:37 pm

Chris Peterson wrote: ↑Mon Sep 02, 2024 1:33 pm

Well, start by considering the density. The density of a prominence is about the same as the density of Earth's atmosphere somewhere between 30 and 50 kilometers above the surface. (The pressure at that height is a fraction of a percent of the surface pressure. Not a hard vacuum, but pretty thin.)

So, then, not much would happen? At what point - if any - does the temperature of a very rarefied plasma become an issue?

Temperature isn't really the issue. Prominences aren't that much hotter than the upper atmosphere as it is. What matters is how much energy can be delivered, and if you don't have many atoms, you can't transfer much energy. (That's how a Thermos works.)

I think the impact on our atmosphere depends on other factors, such as the velocity of the flow around us, and what magnetic fields are doing.

Ok, thanks.

What a fascinating view are prominences of the sun in different shapes, that is a naturally occurring phenomenon of the sun that is overwhelmingly making us wonder what will happen next. Speaking of the sun's future, at present, the sun is getting nova and will get bigger in 3937 as Nostradamus predicted as the end of the World and that was also told in Arthur Clarke's Song of a Distant Earth, and Me, as Moses Kaldor is going to lead a million refugees that will escape from Earth's destruction going to Sagan 2 as our New Earth located in Hoag Galaxy. Let the good force be with us so live forever & prosper!

MelvzLuster wrote: ↑Mon Sep 02, 2024 6:41 pm What a fascinating view are prominences of the sun in different shapes, that is a naturally occurring phenomenon of the sun that is overwhelmingly making us wonder what will happen next. Speaking of the sun's future, at present, the sun is getting nova and will get bigger in 3937 as Nostradamus predicted as the end of the World and that was also told in Arthur Clarke's Song of a Distant Earth, and Me, as Moses Kaldor is going to lead a million refugees that will escape from Earth's destruction going to Sagan 2 as our New Earth located in Hoag Galaxy. Let the good force be with us so live forever & prosper!

Uh,...Ok...Stepping slowly away from the computer...