[meteorite-list] Dust, and millions and millions of years

From: E.P. Grondine <epgrondine_at_meteoritecentral.com>
Date: Tue, 26 Jan 2010 14:59:35 -0800 (PST)
Message-ID: <479186.12857.qm_at_web36901.mail.mud.yahoo.com>

Hi all -

"...approximately 40,000-60,000 t of extraterrestrial material
>>> lands on Earth every year, the majority of which is in the form of tiny
>>> dust grains usually less than 1 mm (1/25 in) in size; importantly, most
>>> of this dust is believed to originate from comets..."

So how massive was the Earth at formation, when the insects ruled, when the reptiles ruled, when the dinosaurs ruled? What percentage of current gravity during each period?

We know that when insects ruled, the Earth's atmosphere had far more oxygen, apparently later out-gassed to space.

I wonder what the long term future holds? Some quick math, Sterling, anyone?

Ed "E.P."


      
Received on Tue 26 Jan 2010 05:59:35 PM PST