Libre said:
Exactly.
The answer is 0.000...0
Mass is a measure of the quantity of matter in an object.
Weight is the gravitational attraction between an object and the Earth, and also, the Earth and that object.
So, with the Earth as a frame of reference, the weight of the Earth is 0.
You would be weightless in space, and so is the Earth. Your mass would not change though.
The question, what is the MASS of the earth, in METRIC TONS is a very different question.
I have no idea what the answer to that one is - I think Miss Shelf may have hit it on the head.
At the risk of provoking even more thinking, or worse yet, provoking Libre, consider the following hypothetical scenario:
I place a chunk of dry ice (frozen Carbon Dioxide) upon a scale, and it happens to register 1 pound (pardon me for not saying a kilo, but I am a true blue North American).
Now, CO2 does not melt in the conventional sense, as frozen water (aka ice) does, but rather
sublimates (ouuu that sounds ever so sexual), and passes directly from the solid phase to the gaseous phase (and remember, plasma is the fourth state of matter).
So we may observe as our chunk of dry ices, evanescently as the Cheshire Cat's smile, approaches as close as we please to a weight of zero. But it is not meaningful to say that it ever reaches zero, for when it disappears, then there is nothing remaining to which we might predicate the qualia of weight.
In Structured Query Language (SQL) there is something called NULL, which is often mistakenly identified as zero. But NULL has a very different meaning. When a field contains null, the null signifies that the value is either unknown, or possibly meaningless. NULL is a big question mark. When we say that something is weightless in space, what we mean is that some astronaught is flailing about with his hands and legs, and must be very cautious about peeing.
It all depends upon how you choose to define weight.
So it may be misleading to say that the Earth has a weight of zero. It may be more meaningful to fill in our weight field with the NULL. Furthermore, the Earth is in a certain orbit precisely because of the gravitational attracting between the Earth, sun, moon, planets, and virtually all the mass in the universe.
All these matters had quickly passed through my mind when I first saw Libres post. But I felt that if I were to cavil about such things, and Libre was actually unaware of the subtle distinction between mass and weight, then I would be perceived as an insensitive, pedantic putz, and Libre would feel even more hurt, and would do something hasty in desperation.
It is not that the object in space becomes weightless, but rather that the concept of weight in space becomes meaningless, or at very least, vague and illusive.
Were we to place the Earth on the surface of Jupiter, it would take up a percentage of Jupiter surface area comparable to New York State's occupation of the earth's surface, or perhaps even New York City's occupation, to hazard a guess. And the earth would definitely have weight on the surface of Jupiter.
And speaking of Jupiter (the name of a deity), if a deity is the source of existence, then one cannot speak of that deity existing, or not existing, just as it is difficult to speak of the weight of the Earth, and yet Earth's mass is the source of our notion of weight.
When anthropoligist Margaret Mead asked some natives where babies come from, they were perfectly conscious of the correct answer, but felt embarrassment and compassion Ms. Mead, as the thought perhaps SHE did not know the answer. So, to be politically correct, they gave the answer which they give to small children, namely, that babies are found under cabbage leaves (or something similar). And Doctor Mead promply published the astounding fact that there exist natives so primitive that they are ignorant of the facts of human reproduction.
What we do for love!
