Introduction

Size of the Universe

In this model, the sun is a very tiny speck of dust indeed—a speck less than a three-thousandth of an inch in diameter … Think of the sun as something less than a speck of dust in a vast city, of the earth as less than a millionth part of such a speck of dust, and we have perhaps as vivid a picture as the mind can really grasp of the relation of our home in space to the rest of the universe. —

Sir James Jeans In The Universe Around Us (1953), 96.

Relative Size of Things

structure	size of structure
coffee bean	12 X 8mm
grain of rice	8 X 2.5mm
sesame seed	3 X 2mm
grain of salt	.5mm
ameba	500 microns
paramecium	210X60 microns
human ovum	130 microns
photoreceptor	100 X 2.5 microns
sperm	60 X 5 microns
skin cell	30 microns
red cell	8 microns
X chromosome	7 microns
baker’s yeast	3 X 4 microns
E Coli bacterium	3 X .6 microns
mitochondrion	4 X .8 microns
lysosyme	.1 micron
measles virus	220 nanometers
influenza virus	130 nm
hiv virus	130 nm
coated vesicle	90 nm
hepatitis virus	45nm
rhinovirus	30nm
ribosome	30nm
ribosome	30nm
antibody	12 nm
tRNA	7nm
phospholipid	.9 X 3.4nm
methionine	1100 X 700pm
adenine	1300 X 760pm
glucose	900pm
water molecule	275pm
carbon atom	340pm

References

Carl Sagan http://www.youtube.com/watch?feature=fvwp&v=t4Tst9DZFPI