How is the mass of the Earth or the Sun measured?

[C18]

TL;DR

Hello , I read the earth and the sun has a mass and google etc gives a measure . When I go the supermarket and buy 1 kg of bananas , they are weighed on scales .

Is science lying about the mass of the earth and the sun ?

Hello , I read the earth and the sun has a mass and google etc gives a measure . When I go the supermarket and buy 1 kg of bananas , they are weighed on scales .

Is science lying about the mass of the earth and the sun ?

 

[Ibix]

Is science lying about the mass of the earth and the sun ?

No. Science is a methodology - it doesn't lie. Scientists might lie, but not in this case. And you'll generally get politer and more helpful answers (from anybody about anything) by at least pretending to assume good faith until shown reasons to think otherwise. Opening up with accusations of dishonesty always makes you look like an arrogant fool, and especially so when they're unfounded.

You can measure the product $GM$ for solar system bodies by studying orbits, and we know $G$ from the Cavendish experiment. Hence we can measure masses of planets and stars. $G$ is our least precisely known physical constant, though, so anything beyond the fourth or fifth digit of such masses is uncertain.

 

[PeroK]

TL;DR Summary: Hello , I read the earth and the sun has a mass and google etc gives a measure . When I go the supermarket and buy 1 kg of bananas , they are weighed on scales .

There are no scales at my local supermarket. If bananas are prepackaged you just have to trust they are the right weight. I usually buy loose bananas, which are priced individually- about 16p each - as I can't get through a whole kg before they've go soft and black.

 

[Ibix]

There are no scales at my local supermarket.

Mine has scales, but apparently "out of order" signs are cheaper than maintenance.

 

[Baluncore]

I kid you not, there is a good introduction to weighing the Earth here;
https://en.wikipedia.org/wiki/Earth_mass

 

[russ_watters]

There are no scales at my local supermarket.

Interesting; in the US, at least at every supermarket ive seen, every checkout counter/barcode scanner is a scale.

 

[DrClaude]

Thread closed for moderation.

 

[berkeman]

The OP has been escorted from the building, so this thread will remain closed.