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This website has been created by and is supported by a group of Boston, MA - area amateur astronomers. It is intended to be a convenient site to access news and information about astronomy and space-related activities of interest to the community and the public.

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Factor	Multiple	Value	Item
10−27	1 yg/m3	1 × 10−27 kg/m3	Very approximate density of the universe
10−26
10−25
10−24	1 zg/m3
10−23
10−22	100 zg/m3	1 × 10−22 kg/m3	Probable lowest observed density of space in galactic spiral arm (1 hydrogen atom every 16 cubic centimeters)
10−21	1 ag/m3
10−20
10−19
10−18	1 fg/m3	1 × 10−18 kg/m3	Observed density of space in core of galaxy (600 hydrogen atoms in every cubic centimetre)
			Best vacuum from a laboratory (1 pPa)[1]
10−17
10−16
10−15	1 pg/m3
10−14		2.0 × 10−14 kg/m3	(2.0 × 10−17 g/cm3) density of Sun's corona[2]
10−13		1.0 × 10−13 kg/m3	(1.0 × 10−16 g/cm3) density at top of solar transition region[2]
10−12	1 ng/m3
10−11		1.0 × 10−11 kg/m3	(1.0 × 10−14 g/cm3) density at bottom of solar transition region[2]
10−10
10−9	1 μg/m3
10−8
10−7
10−6	1 mg/m3
10−5		1.34 × 10−5 kg/m3	Earth atmosphere at 82 kilometre altitude; star Mu Cephei's approximate mean density
10−4	0.1 g/m3	1.09 × 10−4 kg/m3	Earth atmosphere at 68 kilometre altitude
		2.0 × 10−4 kg/m3	(2.0 × 10−7 g⋅cm−3) Density of Solar photosphere–chromosphere boundary[2]
		4.0 × 10−4 kg/m3	(4.0 × 10−7 g⋅cm−3) Density of Solar photosphere's lower boundary[2]
10−3	1 g/m3	1 × 10−3 kg/m3	Vacuum from a mechanical vacuum pump; density of Sun just below its photosphere[2]
10−2	10 g/m3	1.8 × 10−2 kg/m3	Earth atmosphere at 30 kilometre altitude[3]
		9 × 10−2 kg/m3	Hydrogen gas, the least dense substance at STP
10−1	100 g/m3	1.6 × 10−1 kg/m3	Earth atmosphere at 16 kilometre altitude[3]

 

List of orders of magnitude for density 1 kg/m³ and greater
 

Factor	Multiple	Value	Item
100	1 kg/m3	0.9 kg/m3 = 0.0009 g/cm3	Ultralight metallic microlattice.[4]
		1.1 kg/m3 = 0.0011 g/cm3	lowest density achieved for aerogel[5]
		1.48 kg/m3 = 0.00148 g/cm3	Earth atmosphere at sea level
101	10 kg/m3	10 kg/m3 = 0.01 g/cm3	lowest density of typical aerogel[5]
		65 kg/m3 = 0.065 g/cm3	Atmosphere of Venus at surface[6]
102	100 kg/m3	500 kg/m3 = 0.5 g/cm3	highest density of typical aerogel[5]
		534 kg/m3 = 0.534 g/cm3	Lithium at near room temperature
103	1 Mg/m3 1 t/m3	1000 kg/m3 = 1 g/cm3	Liquid water at 4 °C
		1062 kg/m3 = 1.062 g/cm3	Average human body density[7]
		1408 kg/m3 = 1.408 g/cm3	Average density of the Sun
		5515 kg/m3 = 5.515 g/cm3	Average density of the Earth
104	10,000 kg/m3	10,490 kg/m3 = 10.49 g/cm3	Silver (Ag)
		11,340 kg/m3 = 11.34 g/cm3	Lead (Pb)
		13,534 kg/m3 = 13.534 g/cm3	Mercury (Hg)
		19,100 kg/m3 = 19.1 g/cm3	Uranium (U)
		19,250 kg/m3 = 19.25 g/cm3	Tungsten (W)
		19,300 kg/m3 = 19.3 g/cm3	Gold (Au)
		21,450 kg/m3 = 21.45 g/cm3	Platinum (Pt)
		22,560 kg/m3 = 22.56 g/cm3[8]	Iridium (Ir)
		22,590 kg/m3 = 22.59 g/cm3[8]	Osmium (Os), the densest known substance at STP
		41,000 kg/m3 = 41 g/cm3	Hassium (Hs), estimated density, assuming that an isotope featuring a long half-life exists
105		150,000 kg/m3 = 150 g/cm3	Core of the Sun
106	1 Gg/m3
107
108
109	1 Tg/m3		White dwarf
1010
1011
1012	1 Pg/m3
1013		2 × 1013 kg/m3	Universe at end of the electroweak epoch (approximately)
1014
1015	1 Eg/m3
1016
1017		2 × 1017 kg/m3	Atomic nuclei and neutron stars
1018	1 Zg/m3
1019
1020
1021	1 Yg/m3
1022
1023		1023 kg/m3	Density of a hypothetical preon star
...	...	...	...
1096		5.1 × 1096 kg/m3	Planck density	Planck star
∞		∞ kg/m3	Density of a black hole at singularity