Does this explain what generates gravity?

Looks like a giant sun with the edge way over on the right. Absolutely fantastic shot - where were you when you took it (country)?
That was taken in New Plymouth, New Zealand. You can see Mt Taranaki on the left (2518m dormant volcano). At first you could only see the red/purple, but the green/yellow at the bottom appeared later. Of course to the naked eye it was just a dim red glow.
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Indeed! Apparently it had a mag field for the first few hundred to 1 billion yrs, and then it faded. The result is, in combination with the weak gravity, the atmosphere was stripped away. Musky et sl, blithely talk about settling Mars, but the surface is brutal due to UV radiation, and high velocity particles from the Sun. Those are problems that will need to be solved.
Just to put this into perspective, the top 3-4 cm of Martian soil is completely sterile due to solar radiation. Add to that the fact that there are planet wide dust storms every year churning this layer up and making things worse over time. So, nowhere for bacteria to hide.
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What about a force field?

In the far future humankind may be able to live on the surface of Mars under a protective bubble.

View attachment 1309452

We'll just have to work around the problem of the prohibitive amount of power required to maintain the "mini magnetosphere"!

Perhaps a giant Tesla coil? ;)
I definitely prefer to spend summers in Scotland!
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I definitely prefer to spend summers in Scotland!

We had our summer last Saturday.


I have the radiation burns to prove it!
here is a nice description of how s heat pump works

The article refers to an air source heat pump.

Quote: "To become a gas it [the refrigerant] needs energy which it absorbs as heat from the air : this causes little change in its temperature, but does cause its molecules to speed up."

Is there a physicist in the house? Actually there is no change in temperature at all, and the molecules do not speed up!

Energy must be supplied to overcome the forces that hold the molecules together in the liquid state. This energy is called latent heat. By latent we mean hidden because no change in temperature is involved. The molecules may be said to have gained potential energy, not kinetic energy.

The action of an air pump may be briefly summarised as follows:

When the volatile refrigerant in its liquid phase evaporates to its gaseous phase it absorbs latent heat energy.

When the refrigerant in its gaseous phase condenses to its liquid phase it releases latent heat energy.
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a fascinating insight into IMD of my favorite subjects, entropy

Would you regard entropy as being reversible in the air pump scenario?

Latent heat of vaporisation must be added to change the ordered state of the liquid into the disordered gaseous state.

Latent heat of vaporisation is released when the disordered gaseous state changes into the ordered state of the liquid.

P.S. What is IMD?
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Latent heat of vaporisation is released when the disordered gaseous state changes into the ordered state of the liquid.
This cannot happen according to entropy. Nothing goes from a disordered state to an ordered state. There is a transformation of energy as gaseous state moves to a a liquid state and that has to be considered as part of the process - so entropy is not violated.
So are you saying if a gas of liquid heats up, molecules don’t move faster?

No, I am talking about a change of state, not a change of temperature.

During a change of state, the average kinetic energy of the molecules does not increase. Once the change of state is completed, adding more energy would make the molecules move faster (on average).

For example, the average KE of water molecules at 100 degrees C is the same as the average KE of steam molecules at 100 degrees C.
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I don't find heat pumps difficult. Think of a refrigerator sort of inside out and it's got to work more efficiently than plain using electric fires for heating.

If your radiators are at 50C, and the ground sink is 0C, then the improvement is 273/50, or about 5.5 units of heat pumped to the radiators for every unit of electricity consumed. -273C being absolute zero.

This is calculated thermodynamic efficiency, assuming efficient engineering... it never works out quite that well in practise, but I'd have to look it all up to be precise.

I am also quite comfortable with Dark Matter and Dark Energy too. Just we can't detect the stuff directly. Alternatives like MOND Gravity are getting increasingly discredited.

My own most recent engineering improvement was to a slightly precarious and wonky pool ladder, which I considered not up to my own Health and Safety standards on assessment.

I might have broken something if it had slipped sideways, and certainly caused alarm and distress to my person:

Steve at Work.jpg

Couple of securing bungees and clips much improved my potential outcome, I feel. :cool:

Alas my stupid nephew then removed this essential safety feature because he wanted the bungees for the Ping-Pong table cover...

I had to then find some ropes before venturing in again. I take preserving my life seriously. This is why I have lived to a healthy old age! My nephew's prospects are poorer IMO.

I missed the Aurora last weekend. Preferring an early night. The lights from Derby and the local Cloud Quarry made it a poor prospect, but the great nephews took some good snaps on mobile phones from a nearby dark lane.

Even my lovely niece Clare was rabbiting on about Red Oxygen and Blue Nitrogen ionisation... :)

Coverage of the forthcoming exciting T CrB Nova is patchy. The Good:

Located 3,000 light years from Earth, the Corona Borealis is home to a white dwarf star named T Coronae Borealis (or T CrB for short) that's on the verge of what Nasa says will be a once-in-a-lifetime nova eruption.

The rare cosmic event is expected to take place sometime before September 2024. When it occurs it will likely be visible to the naked eye. No expensive telescope will be needed to witness this cosmic performance, says Nasa.

T CrB oubursts only happen about once every 80 years, the last was was back in 1946.

"I'm very excited. This thing is kind of like Halley's Comet – it occurs once every 75 to 80 years – but novas don't get the press Halley's Comet gets," says Nasa’s meteoroid environment program manager William J Cooke. "Comets always get more press."

The Bad. The dumb American newsrooms are getting it all wrong, as usual:

This is west of the Mississippi from the KCRA 3 broadcasting call sign. Los Angeles I guess. East starts with W callsigns. Not many people know that.

T CrB Inaccurate Placing.jpg

You spot the glaring error, of course. A child of ten would. Don't believe the news, I say. It is all nonsense!

T Corona Borealis.png

No sign of the Nova yet. But we are on alert, I hope. I have discussed the need for a tripod and long exposure earlier.

Best, Steve.
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No sign of the Nova yet. But we are on alert, I hope. I have discussed the need for a tripod and long exposure earlier.
Expletive deleted. I had hoped Crb T was going to be as bright as Vega. Which I spotted for the first time last Friday night trying to view the aurora. I am a novice and possibly learning impaired at identifying constellations. Did see the outer rim of the Big Dipper pointing to a blank place in the sky between Vega and a cloud bank obscuring Arcturus. OTOH maybe I have been calling the bright stars of Ursa Major the Big Dipper. Duh!
Walking out at night from my trailer to the northern edge of my property where there are no trees has its own hazards. There are snake holes 2" in diameter, and mole snorkels 6" high. I almost tripped several times. Fortunately the snakes are non-poisonous.
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