astronomical unit | 1 AU | 2 AU | 3 AU | 4 AU | 5 AU | 6 AU | 7 AU | 8 AU | 9 AU | 10 AU | 11 AU | 12 AU | 13 AU | 14 AU | 15 AU | 16 AU | 17 AU | 18 AU | 19 AU | 20 AU | 21 AU | 22 AU | 23 AU | 24 AU | 25 AU | 26 AU | 27 AU | 28 AU | 29 AU | 30 AU | 31 AU | 32 AU | 33 AU | 34 AU | 35 AU | 36 AU | 37 AU | 38 AU | 39 AU | 40 AU | 41 AU | 42 AU | 43 AU | 44 AU | 45 AU | 46 AU | 47 AU | 48 AU | 49 AU | 50 AU | 51 AU | 52 AU | 53 AU | 54 AU | 55 AU | 56 AU | 57 AU | 58 AU | 59 AU | 60 AU | 61 AU | 62 AU | 63 AU | 64 AU | 65 AU | 66 AU | 67 AU | 68 AU | 69 AU | 70 AU | 71 AU | 72 AU | 73 AU | 74 AU | 75 AU | 76 AU | 77 AU | 78 AU | 79 AU | 80 AU | 81 AU | 82 AU | 83 AU | 84 AU | 85 AU | 86 AU | 87 AU | 88 AU | 89 AU | 90 AU | 91 AU | 92 AU | 93 AU | 94 AU | 95 AU | 96 AU | 97 AU | 98 AU | 99 AU | 100 AU |
fermi | 1.495978707 × 1026 fm | 2.991957414 × 1026 fm | 4.487936121 × 1026 fm | 5.983914828 × 1026 fm | 7.479893535 × 1026 fm | 8.975872242 × 1026 fm | 1.0471850949 × 1027 fm | 1.1967829656 × 1027 fm | 1.3463808363 × 1027 fm | 1.495978707 × 1027 fm | 1.6455765777 × 1027 fm | 1.7951744484 × 1027 fm | 1.9447723191 × 1027 fm | 2.0943701898 × 1027 fm | 2.2439680605 × 1027 fm | 2.3935659312 × 1027 fm | 2.5431638019 × 1027 fm | 2.6927616726 × 1027 fm | 2.8423595433 × 1027 fm | 2.991957414 × 1027 fm | 3.1415552847 × 1027 fm | 3.2911531554 × 1027 fm | 3.4407510261 × 1027 fm | 3.5903488968 × 1027 fm | 3.7399467675 × 1027 fm | 3.8895446382 × 1027 fm | 4.0391425089 × 1027 fm | 4.1887403796 × 1027 fm | 4.3383382503 × 1027 fm | 4.487936121 × 1027 fm | 4.6375339917 × 1027 fm | 4.7871318624 × 1027 fm | 4.9367297331 × 1027 fm | 5.0863276038 × 1027 fm | 5.2359254745 × 1027 fm | 5.3855233452 × 1027 fm | 5.5351212159 × 1027 fm | 5.6847190866 × 1027 fm | 5.8343169573 × 1027 fm | 5.983914828 × 1027 fm | 6.1335126987 × 1027 fm | 6.2831105694 × 1027 fm | 6.4327084401 × 1027 fm | 6.5823063108 × 1027 fm | 6.7319041815 × 1027 fm | 6.8815020522 × 1027 fm | 7.0310999229 × 1027 fm | 7.1806977936 × 1027 fm | 7.3302956643 × 1027 fm | 7.479893535 × 1027 fm | 7.6294914057 × 1027 fm | 7.7790892764 × 1027 fm | 7.9286871471 × 1027 fm | 8.0782850178 × 1027 fm | 8.2278828885 × 1027 fm | 8.3774807592 × 1027 fm | 8.5270786299 × 1027 fm | 8.6766765006 × 1027 fm | 8.8262743713 × 1027 fm | 8.975872242 × 1027 fm | 9.1254701127 × 1027 fm | 9.2750679834 × 1027 fm | 9.4246658541 × 1027 fm | 9.5742637248 × 1027 fm | 9.7238615955 × 1027 fm | 9.8734594662 × 1027 fm | 1.00230573369 × 1028 fm | 1.01726552076 × 1028 fm | 1.03222530783 × 1028 fm | 1.0471850949 × 1028 fm | 1.06214488197 × 1028 fm | 1.07710466904 × 1028 fm | 1.09206445611 × 1028 fm | 1.10702424318 × 1028 fm | 1.12198403025 × 1028 fm | 1.13694381732 × 1028 fm | 1.15190360439 × 1028 fm | 1.16686339146 × 1028 fm | 1.18182317853 × 1028 fm | 1.1967829656 × 1028 fm | 1.21174275267 × 1028 fm | 1.22670253974 × 1028 fm | 1.24166232681 × 1028 fm | 1.25662211388 × 1028 fm | 1.27158190095 × 1028 fm | 1.28654168802 × 1028 fm | 1.30150147509 × 1028 fm | 1.31646126216 × 1028 fm | 1.33142104923 × 1028 fm | 1.3463808363 × 1028 fm | 1.36134062337 × 1028 fm | 1.37630041044 × 1028 fm | 1.39126019751 × 1028 fm | 1.40621998458 × 1028 fm | 1.42117977165 × 1028 fm | 1.43613955872 × 1028 fm | 1.45109934579 × 1028 fm | 1.46605913286 × 1028 fm | 1.48101891993 × 1028 fm | 1.495978707 × 1028 fm |
The astronomical unit (symbol: au or ua) is a unit of length, roughly the distance from Earth to the Sun. However, that distance varies as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once a year. Originally conceived as the average of Earth's aphelion and perihelion, it is now defined as exactly 149 597 870 700 metres (about 150 million kilometres, or 93 million miles). The astronomical unit is used primarily as a convenient yardstick for measuring distances within the Solar System or around other stars. However, it is also a fundamental component in the definition of another unit of astronomical length, the parsec.
Name of unit | Symbol | Definition | Relation to SI units | Unit System |
---|---|---|---|---|
astronomical unit | AU | ≡ 149 597 870 700 m ≈ Distance from Earth to Sun | ≡ 149 597 870 700 m | Science - Astronomy (Length) |
astronomical units | fermi | astronomical units | fermi |
---|---|---|---|
1 | ≡ 1.495978707E+26 | 4 | ≡ 5.983914828E+26 |
1.5 | ≡ 2.2439680605E+26 | 4.5 | ≡ 6.7319041815E+26 |
2 | ≡ 2.991957414E+26 | 5 | ≡ 7.479893535E+26 |
2.5 | ≡ 3.7399467675E+26 | 5.5 | ≡ 8.2278828885E+26 |
3 | ≡ 4.487936121E+26 | 6 | ≡ 8.975872242E+26 |
The femtometre (American spelling femtometer, symbol fm derived from the Danish and Norwegian word femten, "fifteen"+Ancient Greek: μέτρον, metrοn, "unit of measurement") is an SI unit of length equal to 10−15 metres, which means a quadrillionth of one. This distance can also be called a fermi and was so named in honour of physicist Enrico Fermi, as it is a typical length-scale of nuclear physics.
Name of unit | Symbol | Definition | Relation to SI units | Unit System |
---|---|---|---|---|
fermi | fm | ≡ 1×10−15 m | ≡ 1×10−15 m | Metric system Non-SI |
fermi | astronomical units | fermi | astronomical units |
---|---|---|---|
1 | ≡ 6.6845871222684E-27 | 4 | ≡ 2.6738348489074E-26 |
1.5 | ≡ 1.0026880683403E-26 | 4.5 | ≡ 3.0080642050208E-26 |
2 | ≡ 1.3369174244537E-26 | 5 | ≡ 3.3422935611342E-26 |
2.5 | ≡ 1.6711467805671E-26 | 5.5 | ≡ 3.6765229172476E-26 |
3 | ≡ 2.0053761366805E-26 | 6 | ≡ 4.0107522733611E-26 |
astronomical units | fermi |
---|---|
1 | ≡ 1.495978707 × 1026 |
6.6845871222684 × 10-27 | ≡ 1 |
Symbol | Definition |
---|---|
≡ | exactly equal |
≈ | approximately equal to |
= | equal to |
digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |