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 centimetres) |
| 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) |
| 10-17 |
10 fg/m³ |
1 × 10-17 kg/m³ |
best vacuum from a laboratory (1.3 nPa) |
| 10-16 |
|
|
|
| 10-15 |
1 picogram (pg)/m³ |
|
|
| 10-14 |
|
2.0 × 10-14 kg/m³ |
density of Sun's corona1 |
| 10-13 |
|
1.0 × 10-13 kg/m³ |
density at top of solar transition region1 |
| 10-12 |
1 nanogram (ng)/m³ |
|
|
| 10-11 |
|
1.0 × 10-11 kg/m³ |
density at bottom of solar transition region1 |
| 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 |
Density of Solar photosphere-chromosphere boundary1 |
| 4.0 × 10-4 kg/m³ |
Density of Solar photosphere's lower boundary1 |
| 10-3 |
1 gram (g)/m³ |
1 gram (g)/m³ |
vacuum from a mechanical vacuum pump;
density of Sun just below its photosphere1 |
| 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 altitudecitation needed |
