Difference between revisions of "Eve"
(split ocean paragraph into its own section and added my speculation about the ocean's composition)
(→Atmosphere: Updated atmospheric pressure per version 1.05)
|Line 46:||Line 46:|
| 20 000 || 29 097 || 0.287
| 20 000 || 29 097 || 0.287
| 25 000 || 16
| 25 000 || 16 || 0.162
| 30 000 || 8
| 30 000 || 8 || 0.082
| 35 000 || 3
| 35 000 || 3 || 0.036
| 40 000 || 1
| 40 000 || 1 || 0.015
| 50 000 ||
| 50 000 || .|| 0.
| 60 000 ||
| 60 000 || .|| 0.002
| 70 000 ||
| 70 000 || .|| 0.
| 80 000 ||
| 80 000 || .|| 0.000
| 90 000 || 0 || 0.000
| 90 000 || 0 || 0.000
Revision as of 20:33, 12 November 2015
|Eve as seen from orbit.|
|Planet of Kerbol|
|Semi-major axis||9 832 684 544 m [Note 1]|
|Apoapsis||9 931 011 387 m [Note 1]|
|Periapsis||9 734 357 701 m [Note 1]|
|Orbital inclination||2.1 °|
|Argument of periapsis||0 °|
|Longitude of the ascending node||15 °|
|Mean anomaly||3.14 rad (at 0s UT)|
|Sidereal orbital period||5 657 995 s|
|261 d 5 h 39 m 55.1 s|
|Synodic orbital period||14 687 035.5 s|
|Orbital velocity||10 811 - 11 029 m/s|
|Equatorial radius||700 000 m|
|Equatorial circumference||4 398 230 m|
|Surface area||6.1575216×1012 m2|
|Standard gravitational parameter||8.1717302×1012 m3/s2|
|Density||85 219.677 kg/m3|
|Surface gravity||16.7 m/s2 (1.701 g)|
|Escape velocity||4 831.96 m/s|
|Sidereal rotation period||80 500.000 s|
|3 d 4 h 21 m 40 s|
|Solar day||81 661.857 s|
|3 d 4 h 41 m 1.9 s|
|Sidereal rotational velocity||54.636 m/s|
|Synchronous orbit||10 328.47 km|
|Sphere of influence||85 109 365 m [Note 1]|
|Atmosphere present||✓ Yes|
|Atmospheric pressure||506.625 kPa|
|Atmospheric height||90 000 m|
|Temperaturemin||-113.13 °C 160.02 K|
|Temperaturemax||146.85 °C 420 K|
|Oxygen present||× No|
Eve is the second planet from Kerbol, the closest planet to Kerbin, and KSP's analogue for the planet Venus. It has one small moon: a captured asteroid called Gilly. Mainly because of the atmosphere it's the hardest planet to return from after landing. Additionally, it has the highest surface gravity in the game, and the second highest radius (only Jool's radius is larger). Aerobraking on Eve is also more deadly due to its dense atmosphere, which means spacecraft are more likely to explode due to overheating before reaching land.
|“|| Eve is certainly the purplest object in the solar system. Its one of the larger, most visible objects, mainly because of its very, very purple tint.
It is considered by some to be an almost sister planet to Kerbin. Well, despite the purple, and the toxic atmosphere, and the extreme pressures and temperatures… Actually, it’s not very similar at all is it? Who are these people?
The surface of Eve looks not unlike that of Saturn's largest moon, Titan. It has several oceans, among which lie large, flat continents. The terrain has a few mountain peaks, but mostly consists of rolling hills that resemble purple sand dunes. These are speckled with small boulders, no doubt worn down by Eve's pressure, temperature, and wind. Eve's surface is covered with craters. Eve's highest mountain range has a peak of 7526 m.
Eve has an extremely dense atmosphere with a mass of approximately 1.9×1017 kilograms, a sea level pressure of 506.625 kilopascals (5 atmospheres), and a depth of 90,000 meters. Compared to the atmosphere of Kerbin, Eve's atmosphere has 4 times the mass and 5 times the sea level pressure. At an altitude of 10,577 m on Eve, the atmospheric pressure is the same as at sea level on Kerbin (1 atm). The pressure at the top of Eve's highest mountain peak is 1.5 atm.
The average molecular weight of Eve air is 43 g/mol, and its adiabatic index is 1.20. Although the composition of Eve's atmosphere is unknown, these values suggest that it may consist largely of carbon dioxide. Another possibility is that the atmosphere is filled with ethane gas (C2H6, heat capacity of 1.2, molecular weight of 30 g/mol) and other compounds. If we assume LiquidFuel is kerosene, the joke that the lakes of Eve are LiquidFuel is strengthened by the purple colour since it is often mixed with a purple dye prior to sale. With a thick atmosphere filled with hydrocarbons, it's easy to imagine reactions that would yield compounds such as C12H26 (RP-1, kerosene used as rocket fuel). An atmosphere of 90% CO2 and 10% C2H6 would have molecular weights and adiabatic indexes close to what is seen on Eve, though there are other combinations of gasses that would work as well.
Like all other atmospheres in the game, Eve's atmosphere fades exponentially as altitude increases. The scale height varies with altitude, which is a change from pre-1.0 versions of the game. The pressure-altitude profile is globally constant and independent of temperature. The following table gives the atmospheric pressure at various altitudes above sea level.
|Altitude (m)||Pressure (Pa)||Pressure (atm)|
|2 500||329 212||3.249|
|5 000||217 760||2.149|
|7 500||151 432||1.495|
|10 000||109 422||1.080|
|12 500||77 912||0.769|
|15 000||54 946||0.542|
|20 000||29 097||0.287|
|25 000||16 457||0.162|
|30 000||8 327||0.082|
|35 000||3 688||0.036|
|40 000||1 526||0.015|
The surface of Eve is very hot, with a globally averaged sea level temperature of approximately 135 °C. Except for a small inversion layer between 50-60 km at low latitudes, air temperatures decrease with increasing altitude up to an altitude of 70 km. Above 70 km, the rarified atmosphere warms as altitude increases. Despite the hot surface temperatures, the lack of a stratosphere means that Eve's atmosphere is cooler than Kerbin's at altitudes above ≈26.5 km. The temperature rise above 70 km suggests the presence of a thermosphere.
Air temperatures vary with latitude and time of day. At the equator, sea level temperatures vary between a nighttime low of 147 °C and a daytime high of 156 °C. At the poles, the temperature varies between 87 °C and 95 °C. Since Eve has no axial tilt, there are no seasonal temperature variations.
From within Eve's atmosphere, the sky appears indigo during nighttime and a violet-purple color during daytime. During dawn and dusk, the sky is green.
The thickness of Eve's atmosphere makes it well suited for aerobraking from a high-speed interplanetary intercept. The periapsis altitude required for a successful aerocapture depends on the spacecraft's drag characteristics, its approach velocity, and the desired apoapsis of the resulting orbit. For an intercept originating from Kerbin, a periapsis altitude of about 70,000 m should, under most conditions, result in an aerocapture.
Parachutes work very effectively in Eve's dense atmosphere. A vehicle in Kerbin's atmosphere would require 3 times as much parachute area to attain the same descent rate on Eve.
Jet engines do not function in Eve's atmosphere, since it contains no oxygen — they make noise and consume fuel, but they produce no thrust. Planes with other propulsion methods do, however, work very well, and are a great way to explore the planet. They work best between 35 km and 25 km where the atmosphere generates enough lift to glide and steer, but not enough drag to slow the aircraft excessively.
Landing legs on Eve can easily break because of Eve's high gravity and, surprisingly enough, atmospheric pressure.
A large portion of Eve is covered in liquid, making it one of only three celestial bodies with oceans. The composition of the violet liquid which fills the oceans and lakes is unknown, but it has a higher density than water, at 1.5 tonnes/m3.. According to the devs during a livestream, it was joked that the lakes were made of rocket fuel. One liquid that closely fits both of these characteristics is hydrogen peroxide (H2O2), which has a density of 1.450 tonnes/m3 and can be used as monopropellant.
Eve's orbit and atmosphere have a science multiplier of 7, which is rather average. But the surface has a multiplier of 12, which is the third highest science multiplier in the whole star system. Eve has 7 biomes with their own science to be collected. It has several Explodium Seas, among which lie large continents.
Visiting Eve potentially requires the least delta-v of any planet because its huge gravity well and dense atmosphere mitigate the difficulties that its slight relative inclination poses and greatly ease aero-captures, transfers, and landings; unfortunately, takeoff and escape therefore require the most delta-v of any celestial body with a solid surface.
The combination of high gravity and thick atmosphere makes return missions from the sea level of Eve very difficult. It requires about 11,500 m/s of delta-v to get into orbit from sea level. Driving to and launching from the peak of one of Eve's mountains can drastically reduce the amount of delta-V required (thus allowing successful launches with significantly lighter rockets). The highest peak on Eve since version 0.21.1 is 7540 m high, found near (25° S, 158.5° W)
|Altitude (m)||Delta-V Required (m/s)|
A synchronous orbit of Eve requires an altitude of 10373.195 km and a velocity of 858.95 m/s. For a semi synchronous orbit of ½ an Eve day (11.25 hours or 40500 seconds) an orbit of 6275.676 km above Eve is needed with a velocity of 1082.2 m/s.
|Time warp||Minimum Altitude|
|5×||90 000 m (above the atmosphere)|
|10×||90 000 m (above the atmosphere)|
|50×||90 000 m (above the atmosphere)|
|100×||120 000 m|
|1 000×||240 000 m|
|10 000×||480 000 m|
|100 000×||600 000 m|
- Eve has higher gravity than Kerbin, restricting a Kerbal's jump to only half a meter and making EVA jets useless. This being said, if a Kerbal falls from more than 4 m, they will hit the ground much harder than on Kerbin, which may cause a glitch to happen in which they will clip into the terrain and accelerate away from Eve at phenomenal speed, sometimes faster than the speed of light itself, usually sending the unlucky Kerbal on an escape trajectory from Kerbol if they are not killed by the fall. They may bring something into interstellar space with them if they hit an object instead of the ground.
- Solar panels will probably break off in flight, even with very low velocity. It's best to wait to extend them till stable on the surface, however they can break on the surface of Eve even when retracted. This may be due to Eve's high gravity.
- Rovers can be challenging to drive on Eve due to its gravity, as the rover's wheels will easily break, but on the upside, since the gravity pulls them lower on their shocks and thus lower the centre of mass, they will be harder to flip over. Although not a glitch, it could cause clipping issues with a Kerbal sitting in EAS-1 External Command Seats
- When landing fast, craft will sometimes sink into the surface of Eve. This can be fixed by using landing legs or engines to lift the ship up.
- Added biomes
- Terrain Tweaks — more land mass to the surface
- Art pass.
- Terrain tweaks — the tallest points are now about 6 km in altitude, compared to 11 km before.
- Initial Release
- As of 1.0.5, oceans now have explicit density values: Eve's oceans now have a density of 1.5 tonnes/m3, while water has a density of 1.0 tonnes/m3.