This isn't really about astronomy as in "star gazing", but it's sort-of about space and the universe and physics, and I'm posting here because I think that the Bad Astronomer and I are on the same side of an argument, but not necessarily the right side.

The owner of http://ourworld.compuserve.com/homep...ard/weight.htm dropped into my favourite Usenet newsgroup to tell me off for repeating what he considers to be a fallacy - that pounds measure weight, force,
gravity, whereas kilogrammes measure mass. He says that they're _both_ mass, and, furthermore, that "weight" usually means mass anyway.

I presume that everyone here appreciates the necessary distinctions between physical quantities; when sent to places where the force of gravity is different to the average Earth sea-level altitude gravity, objects "weigh" less (or more) whilst having the same mass.

So anyway, I thought, "Who do I respect on the Internet, that knows about stuff like this?" So, Doctor, here I am [img]/phpBB/images/smiles/icon_wink.gif[/img]

On http://www.badastronomy.com/bad/misc/planets.html our host takes the line pounds = weight, but admits having carelessly written kilograms = weight in a previous article.

Well, then, who's right? Gene Nygaard doesn't come over as a guy who's arguing without checking his facts, or without taking note of contrary evidence. But I don't know how to evaluate the question.

I do know that pounds as a scientific measurement are dead, dead, dead, baby, even before someone used them to fly a spaceprobe smack into the side of a certain planet, and defending pounds against an allegedly false charge that they measure the wrong quantity is not going to change that [img]/phpBB/images/smiles/icon_wink.gif[/img]