https://arxiv.org/ftp/arxiv/papers/1107/1107.2804.pdf
Magnetic Fields in Earth-like Exoplanets and Implications for Habitability around M-dwarfs Mercedes López-Morales1,3, Natalia Gómez-Pérez2,3, Thomas Ruedas3 1 Institut de Ciències de L’Espai (CSIC-IEEC), Barcelona, Spain 2 Departamento de Física, Universidad de Los Andes, Bogotá, Colombia 3 Carnegie Institution of Washington, Department of Terrestrial Magnetism, Washington D.C., USA e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.; phone: +34 93 581 4369; fax: +34 93 581 4363
Magnetic Fields in Earth-like Exoplanets and Implications for Habitability around M-dwarfs Mercedes López-Morales1,3, Natalia Gómez-Pérez2,3, Thomas Ruedas3
Habitability critically depends on a number of factors that control the planet’s surface conditions, among them the surface temperature and the shielding level against incident energetic charged particles.
Those effects have been stated to affect habitability by inducing both uneven heating of the planet’s atmosphere and surface, and a strong reduction of dynamo-generated magnetic shielding (e.g. Griessmeier et al. 2005; Griessmeier et al. 2009).
Recent calculations by e.g. Correia et al. (2008), Barnes et al. (2009) and Heller et al. (2011) suggest that the planets may in fact end in stable nonsynchronous rotation states if their orbits are slightly eccentric.
http://www.astronomynotes.com/solarsys/plantblb.htm
This data is from the National Space Science Data Center's Fact Sheet site. Click on a planet's name to bring up the fact sheet at NSSDC. I have put together a list of links to excellent tours of each planet. Click here to bring up that list.
| Planet | g | vesc | distance | albedo | temperature | atm. press. | atm. comp. | rotation | mag. field |
|---|---|---|---|---|---|---|---|---|---|
| (* gE) | (km/s) | (A.U.) | (%) | (K) | (* Earth's) | (* Earth's) | |||
| Mercury | 0.378 | 4.3 | 0.387 | 5.6 | 100 night, 590--725 day |
10-15 | 98% He, 2% H2 | 58.81 d | 0.006 |
| Venus | 0.907 | 10.36 | 0.723 | 72 | 737 | 92 | 96.5% CO2, 3.5% N2, 0.015% SO2 |
243.69 d | 0.00 |
| Earth | 1.000 | 11.186 | 1.000 | 38.5 | 283--293 day | 1.000 | 78.084% N2, 20.946% O2, 0.934% Ar, 0.035% CO2, H2O highly variable (< 1%) |
23.9345 h | 1.000 |
| Mars | 0.377 | 5.03 | 1.524 | 16 | 184--242 day | 0.007--0.009 | 95.32% CO2, 2.7% N2 1.6% Ar, 0.13% O2, 0.08% CO, 0.021% H2O, 0.01% NO |
24.623 h | 0.00 |
| Jupiter | 2.364 | 59.5 | 5.203 | 70 | 165 | > > 100 | 89% H2, 11% He, 0.2% CH4, 0.02% NH3 |
9.925 h | 19,519 |
| Saturn | 0.916 | 35.5 | 9.539 | 75 | 134 | > > 100 | 89% H2, 11% He, 0.3% CH4, 0.02% NH3 |
10.50 h | 578 |
| Uranus | 0.889 | 21.3 | 19.182 | 90 | 76 | > > 100 | 89% H2, 11% He | 17.24 h | 47.9 |
| Neptune | 1.125 | 23.5 | 30.06 | 82 | 72 | > > 100 | 89% H2, 11% He | 16.11 h | 27.0 |
| Pluto | 0.0675 | 1.1 | 39.53 | 14.5 | 50 | 0.003 | CH4, N2 | 6.405 d | 0.00 |
Notes: Surface gravityg is given in Earth gravities (1 gE = 9.803 m/s2); escape velocity is vesc; albedo is the percent of ALL of the Sun's energy hitting the planet that is reflected (100% would be perfect reflection); temperature and surface gravity for Jupiter, Saturn, Uranus, Neptune are given at a depth where the atmospheric pressure = 1 Earth atmosphere; atmospheric pressure(atm. press.) is at the surface (> > 100 for the jovian planets); rotation is the sidereal rotation period, h = hours and d = days; magnetic field (mag. field) is the total strength (NSSDC gives strength in #gauss × Rplanet3, where Rplanet is the radius of the planet and Earth's strength = 0.3076 gauss × RE3 = 7.981×1010 gauss.