How Big Are Things? Home     Welcome	small		Real world	big			solar system		between	galaxy
	nano	micro		meter	kilo		Mega	Giga	Tera	Peta	Exa

um = 10-6 m

look at the entire room

galaxy		21
		20 19
local stars		18
		17 16
between		15
		14 13
E's orbit		12
		11 10
sun		9
		8 7
texas		6
		5 4
hood		3
		2 1
you		0
		-1 -2
salt grain		-3
		-4 -5
bacteria		-6
		-7 -8
atom		-9

bacteria ~1 um red blood cell ~10 um

hair ~100 um diameter

Looks like a tree trunk?

paramecium Source, image "Courtesy of Sidney Tamm". (Looks odd? I wonder if it's dead and dried out.)

toilet-paper tube

src q-tip cotton
Looks like twigs?

a bacteria "train" from my mouth

inches  mils (1/1000 inch)
0	1	2	3	4	5	6

1200 dpi
600 dpi
your screen dot

Amoeba

human egg

    ... most Prokaryotic cells
... most Eukaryotic animal cells

src, image

human chromosomes

human red blood cell
capillary blood vessel
... rbc's fit through because they are squishy.
Hmm... another source claims 8-10 um...?

air

air goo wall capillary

alveoli wall (~300um balloon)

if you were inside the alveoli, it would look somewhat like being in those big theaters here with the round roofs, and you can look up and you can see sort of a tiled effect? That's kind of what you might imagine. You'll see these cells that are attached together much like tiles are on a floor. src[edited]

Saran wrap (kitchen plastic wrap)

thin aluminum foil (used in laminates)
typical kitchen foil
typical aluminum tray
thick aluminum foil (thicker than 200 um is called "sheet" rather than "foil" :)

src pollen

pin head (size approximate ±~15%) source, img

cilia (min/max)

... amoeba cyst src

... sneeze droplets src

: ... ... yeast src

corner of a grain of salt

single optical fiber (no coating) src

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