Credit & Copyright: Jack Cook, Adam Nieman,
Woods Hole Oceanographic Institution,
Howard Perlman,
USGS
Explanation:
How much of planet Earth is made of water?
Very little, actually.
Although
oceans of water cover about
70 percent of Earth's surface, these oceans are
shallow compared to the Earth's radius.
The featured illustration
shows what would happen if all of
the water on or near the surface of the Earth were bunched up into a ball.
The radius of this ball would be only about 700 kilometers, less than half the radius
of the
Earth's Moon, but slightly larger than Saturn's moon
Rhea which, like many moons in our outer Solar System,
is mostly water ice.
How even this much
water came to be on
the Earth and whether any significant amount is
trapped far
beneath Earth's surface remain topics of research.
Poll:
Have you seen today's APOD image before?
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
Yanvar' Fevral' Mart Aprel' Mai Iyun' Iyul' Avgust Sentyabr' Oktyabr' Noyabr' Dekabr' |
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
|
Publikacii s klyuchevymi slovami:
Earth - water - Zemlya
Publikacii so slovami: Earth - water - Zemlya | |
Sm. takzhe:
Vse publikacii na tu zhe temu >> | |
