APOD: Bright Planetary Nebula NGC 7027... (2020 Jun 30)

[neufer]

Click to play embedded YouTube video.

[BDanielMayfield]

As awful as it sounds, I would guess that the helonium acid is not any worse than ionized hydrogen is already.

Interesting point Mark. Is there a chemist in the house?

I was trying to make it sound as awful as I could, while still being factual. Also, there's the fact that since it reacts with everything, it can also be neutralized by everything.

Cancel Red Alert.

He he. And now I feel bad for being a spoil-sport about it.
The red alert might be warranted, for all I know.

Here's one of the many examples of how space (even very near to home) messes with my intuition:

From Wikipedia's article on the Thermosphere https://en.wikipedia.org/wiki/Thermosphere

The highly attenuated gas in this layer can reach 2,500 °C (4,530 °F) during the day. Despite the high temperature, an observer or object will experience cold temperatures in the thermosphere, because the extremely low density of gas (practically a hard vacuum) is insufficient for the molecules to conduct heat. A normal thermometer will read significantly below 0 °C (32 °F), at least at night, because the energy lost by thermal radiation would exceed the energy acquired from the atmospheric gas by direct contact.

I find this odd: Don't go flying around up in the thermosphere without some protection. Why? Because you'll quickly freeze to death up in that 2,500 °C air. That was hard for me to reconcile.

It's the fact that vacuum and near vacuum is such good thermal insulation. A good thermos bottle is basically just two nested bottles with vacuum in between them.

Back to the subject of the nebula NGC 7027, I wouldn't want to mess with helonium acid. If a molecule of it hit our spaceship, it would give away its proton, and it would damage the ship. But it depends on how much of it is around, or how much of it we needed to fly through, I guess.

And we already know how to shield against acid clouds; just positively charge the hull.

[neufer]

With double shielding around the Mentos

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I wouldn't want to mess with helonium acid. If a molecule of it hit our spaceship, it would give away its proton, and it would damage the ship. But it depends on how much of it is around, or how much of it we needed to fly through, I guess.

And we already know how to shield against acid clouds; just positively charge the hull.

[Ann]

Interesting point Mark. Is there a chemist in the house?

I was trying to make it sound as awful as I could, while still being factual. Also, there's the fact that since it reacts with everything, it can also be neutralized by everything.

Cancel Red Alert.

He he. And now I feel bad for being a spoil-sport about it.
The red alert might be warranted, for all I know.

Here's one of the many examples of how space (even very near to home) messes with my intuition:

From Wikipedia's article on the Thermosphere https://en.wikipedia.org/wiki/Thermosphere

The highly attenuated gas in this layer can reach 2,500 °C (4,530 °F) during the day. Despite the high temperature, an observer or object will experience cold temperatures in the thermosphere, because the extremely low density of gas (practically a hard vacuum) is insufficient for the molecules to conduct heat. A normal thermometer will read significantly below 0 °C (32 °F), at least at night, because the energy lost by thermal radiation would exceed the energy acquired from the atmospheric gas by direct contact.

I find this odd: Don't go flying around up in the thermosphere without some protection. Why? Because you'll quickly freeze to death up in that 2,500 °C air. That was hard for me to reconcile.

It's the fact that vacuum and near vacuum is such good thermal insulation. A good thermos bottle is basically just two nested bottles with vacuum in between them.

The X-ray glow (shown here in purple) emitted by the hot gas that pervades the galaxy cluster XLSSC006. Credit: ESA/XMM-Newton (X-rays); CFHT-LS (optical); XXL Survey.

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I think it's called heat conductivity or thermal conductivity. Certain kinds of heat gets transferred to you very effectively, like, for example, if you spill boiling hot water on yourself. The boiling water will transfer its heat to you very efficiently and give you burns.

But very rarefied gas won't transfer its heat to you at all, or so I believe. That's why you would quickly freeze to death in the million-degree intracluster gas of big galaxy clusters.

Ann

[TheZuke!]

Back to the subject of the nebula NGC 7027, I wouldn't want to mess with helonium acid. If a molecule of it hit our spaceship, it would give away its proton, and it would damage the ship. But it depends on how much of it is around, or how much of it we needed to fly through, I guess.

Yeah, I hadn't figured on hydrogen embrittlement, it looks like I need to redesign the hull of my spacecraft to mitigate such damage.

[BDanielMayfield]

Back to the subject of the nebula NGC 7027, I wouldn't want to mess with helonium acid. If a molecule of it hit our spaceship, it would give away its proton, and it would damage the ship. But it depends on how much of it is around, or how much of it we needed to fly through, I guess.

Yeah, I hadn't figured on hydrogen embrittlement, it looks like I need to redesign the hull of my spacecraft to mitigate such damage.

As per Captain Jonathan Archer of the first Enterprize

polarize the hull plating!

[Hyperborean]

Have we seen this with any other nebulae, ejecting different material at different times in its history?