Orders of magnitude (density)

Skylab measured several orders of magnitude of the Sun's density (top scale: 10⁻¹⁸ to 10⁻⁶ g⋅cm⁻³, equivalent to 10⁻¹⁵ to 10⁻³ kg⋅m⁻³) at different temperatures and heights above its surface.

List of orders of magnitude for density less than 1 kg/m³

Factor	Multiple	Value	Item
10−27	1 yoctogram yg/m3	1 × 10−27 kg/m3	Very approximate density of the universe
10−24	1 zeptogram zg/m3
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 attogram ag/m3
10−20
10−19
10−18	1 femtogram 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 picogram 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 nanogram 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 microgram μg/m3
10−8
10−7
10−6	1 milligram 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 gram 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 gram g/m3	1 gram g/m3	Vacuum from a mechanical vacuum pump; density of Sun just below its photosphere[2]
10−2	10 gram g/m3	1.35 × 10−2 kg/m3	Earth atmosphere at 32 kilometre altitude
		90 g/m3	Hydrogen gas, the least dense substance at STP
10−1		1.66 × 10−2	Earth atmosphere at 16 kilometre altitude[citation needed]

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

Factor	Multiple	Value	Item
100	1 kilogram kg/m3	0.9 kg/m3 = 0.0009 g/cm3	Ultralight metallic microlattice.[3]
		1.48 kg/m3 = 0.00148 g/cm3	Earth atmosphere at sea level
		3 kg/m3 = 0.003 g/cm3	date=February 2009|reason=looks like an extremely low, not typical, density; aerogel is
101
102		534 kg/m3 = 0.534 g/cm3	Lithium at near room temperature
103	1 megagram Mg/m3 1 tonne t/m3	1000 kg/m3 = 1 g/cm3	Liquid water at 4 °C
		1010 kg/m3 = 1.01 g/cm3	Average human body
		1400 kg/m3 = 1.4 g/cm3	Average density of Sun
104	10000 kg/m3	10490 kg/m3 = 10.49 g/cm3	Silver (Ag)
		11340 kg/m3 = 11.34 g/cm3	Lead (Pb)
		13534 kg/m3 = 13.534 g/cm3	Mercury (Hg)
		19100 kg/m3 = 19.1 g/cm3	Uranium (U)
		19250 kg/m3 = 19.25 g/cm3	Tungsten (W)
		19300 kg/m3 = 19.3 g/cm3	Gold (Au)
		21450 kg/m3 = 21.45 g/cm3	Platinum (Pt)
		22560 kg/m3 = 22.56 g/cm3[4]	Iridium (Ir)
		22590 kg/m3 = 22.59 g/cm3[4]	Osmium (Os), the densest known substance at STP
105		150,000 kg/m3 = 150 g/cm3	Core of the Sun
106	1 gigagram Gg/m3
107
108
109	1 teragram Tg/m3		White dwarf
1010
1011
1012	1 petagram Pg/m3
1013	1 × 1013 kg/m3	2 × 1013 kg/m3	Universe at end of electroweak epoch (approximately)
1014
1015	1 exagram Eg/m3
1016
1017		2 × 1017 kg/m3	Atomic nuclei and neutron stars
1018	1 zettagram Zm/m3
1019
1020
1021	1 yottagram Yg/m3
1023		1023 kg/m3	Density of a hypothetical preon star
1096		5.1 × 1096 kg/m3	Planck density
∞		∞ kg/m3	Density of a black hole at singularity

Notes

1. ^ http://dx.doi.org/10.1016/0042-207X(93)90084-N
2. ^ ^{a b c d e f} "SP-402 A New Sun: The Solar Results From Skylab". http://history.nasa.gov/SP-402/p2.htm. 
3. ^ "Ultralight Metallic Microlattices". http://www.sciencemag.org/content/334/6058/962. 
4. ^ ^{a b} Arblaster, J. W. (1989). "Densities of osmium and iridium: recalculations based upon a review of the latest crystallographic data" (PDF). Platinum Metals Review 33 (1): 15. http://www.platinummetalsreview.com/pdf/pmr-v33-i1-014-016.pdf. "at 20^oC" 

External links

• ex.ac.uk - Conversion Calculator for Units of Density