Astronomical UnitsAstronomical UnitsLast revised: 05/22/01 07:28 PM
|
Unit |
Symbol |
Value/Conversion |
Unit |
| Astronomical
Unit
(the average distance from the center of the Earth to the center of the Sun) |
AU
or ua |
1.496 x 1013 | cm |
| 1.496 x 1011 | m | ||
| 1.496 x 108 | km | ||
| 9.296 x 107 | mi | ||
| Light
Year
(distance that light travels in one year) |
ly | 9.46 x 1017 | cm |
| 9.46 x 1015 | m | ||
| 9.46 x 1012 | km | ||
| 5.88 x 1012 | mi | ||
| 63,253 | AU | ||
| Parsec
(distance at which a star appears to shift its position by one arcsecond over the time [about 3 months] in which the Earth moves a distance of one AU in the direction perpendicular to the direction to the star) |
pc | 648,000/pi AU | (by definition) |
| 3.09 x 1018 | cm | ||
| 3.09 x 1016 | m | ||
| 3.09 x 1013 | km | ||
| 1.92 x 1013 | mi | ||
| 206,264.8 | AU | ||
| 3.261 | ly | ||
| hubble | hubble | 109 | ly (by definition) |
| 306.59 | Mpc | ||
| Velocity
of light
(a unit of velocity equal to the speed of light in a vacuum) |
c | 2.998 x 1010 | cm/s |
| 2.998 x 108 | m/s | ||
| 299,792.458 | km/s | ||
| 1.079 x 109 | km/hr | ||
| 186,282.583 | mi/s | ||
| 6.707 x 108 | mi/hr | ||
| Hubble constant | H0 | 60..75 | km/s/Mpc |
| 18..23 | km/s/ly | ||
| Earth Gravitational
constant
(average acceleration produced by gravity at the Earth's surface) |
g | 9.807 | m/s2 |
| 32.174 | ft/s2 | ||
| Earth radius | Re | 6.378 x 106 | m |
| 6,378 | km | ||
| 3,986 | mi | ||
| Solar radius | Rs | 6.96 x 108 | m |
| 696,000 | km | ||
| 435,000 | mi | ||
| Earth Mass | Me | 5.98 x 1024 | kg |
| 1.318 6 x 1028 | lb | ||
| Solar Mass | Ms | 1.99 x 1030 | kg |
| 4288 x 1033 | lb | ||
| Kilometer | km | 1000 | m |
| 0.6214 | mi | ||
| Miles | mi | 1.609 | km |
| Ton | t (US short) | 2000 | lb |
| megaton of TNT | Mt | 4.1 x 1022 | ergs |
| 4.1 x 1015 | joules | ||
| 4.4 x 1014 | kg-meters | ||
| 1.13 x 1012 | kilowatt-hrs | ||
| 3.06 x 1012 | Btu | ||
| Ergs | .0000001 | joules | |
| 1.02 x 10-8 | kg-meters | ||
| 2.78 x 10-11 | kilowatt-hrs | ||
| 7.48 x 10-11 | Btu |
| Number Name | Power of Ten |
| One | 10^0 |
| Ten | 10^1 |
| Hundred | 10^2 |
| Thousand | 10^3 |
| Million or mega | 10^6 |
| Billion | 10^9 |
| Trillion | 10^12 |
| Quadrillion | 10^15 |
| Quintillion | 10^18 |
| Sextillion | 10^21 |
| Septillion | 10^24 |
| Octillion | 10^27 |
| Nonillion | 10^30 |
| Decillion | 10^33 |
| Undecillion | 10^36 |
| Dodecillion | 10^39 |
| Tredecillion | 10^42 |
| Quattuordecillion | 10^45 |
| Quindecillion | 10^48 |
| Sexdecillion | 10^51 |
| Septendecillion | 10^54 |
| Octodecillion | 10^57 |
| Novemdecillion | 10^60 |
| Vigintillion | 10^63 |
| Unvigintillion | 10^66 |
| Dovigintillion | 10^69 |
| Trevigintillion | 10^72 |
| Quattuorvigintillion | 10^75 |
| Quinvigintillion | 10^78 |
| Sexvigintillion | 10^81 |
| Septenvigintillion | 10^84 |
| Octovigintillion | 10^87 |
| Novemvigintillion | 10^90 |
| Trigintillion | 10^93 |
| Unrtigintillion | 10^96 |
| Dotrigintillion | 10^99 |
| Googol | 10^100 |
| Tretrigintillion | 10^102 |
| Quattuortrigintillion | 10^105 |
| Quintrigintillion | 10^108 |
| Sextrigintillion | 10^111 |
| Septentrigintillion | 10^114 |
| Octotrigintillion | 10^117 |
| Novemtrigintillion | 10^120 |
| Googolplex | 10^10googols |
There is no rational need for any larger number to exist in this universe because there are no more than a Trigintillion (10^93) elemental particles in the known universe. There aren't even enough particles in the universe to write the number!