Pulsars and neutron stars/Useful parameters and constants
- Speed of light: 299 792 458m/s
- 1 parsec = 3.0857 x 1016m = 3.26156 ly
- 1 G = 10-4 T
The solar system
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- 1 astronomical unit AU: 1.4960 x 1011m
| Planet |
Mass (solar mass) |
Orbital period (yr) |
Semi-major axis (AU)
|
| Mercury |
|
0.24 |
0.39
|
| Venus |
|
0.62 |
0.72
|
| Earth |
|
1.00 |
1.00
|
| Mars |
|
1.88 |
1.52
|
| Jupiter |
|
11.86 |
5.20
|
| Saturn |
|
29.46 |
9.54
|
| Uranus |
|
84.01 |
19.22
|
| Neptune |
|
164.8 |
30.06
|
Time and dates
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Modified Julian Date
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| Date |
MJD
|
| 17th Nov 1858 |
0
|
| 1 Jan 1968 |
39856
|
| 1 Jan 1980 |
44239
|
| 1 Jan 1990 |
47892
|
| 1 Jan 1995 |
49718
|
| 1 Jan 2000 |
51544
|
| 1 Jan 2005 |
53371
|
| 1 Jan 2010 |
55197
|
| 1 Jan 2015 |
57023
|
| 1 Jan 2016 |
57388
|
