v2.1.1 Bugs Thread

[jamac41]

A possible bug, though it may also be `the wonders of space': I've found a planet of unusually low density - included in the attached screenshot, it has the same gravity as Mars but over 13 times the volume.  By my calculations, it has a density of a little under 0. 29g/m³.  For comparison, pumice has a density of 0. 25 g/m³.  Maybe it's a Naboo-style planet with a cave system at its centre?

[nuclearslurpee]

A possible bug, though it may also be `the wonders of space': I've found a planet of unusually low density - included in the attached screenshot, it has the same gravity as Mars but over 13 times the volume.  By my calculations, it has a density of a little under 0. 29g/m³.  For comparison, pumice has a density of 0. 25 g/m³.  Maybe it's a Naboo-style planet with a cave system at its centre?

By my calculations, the planet in question appears to have a density of 2.2 g/cm³ which seems reasonable. Mars is 3.9 g/cm³ for comparison.

Quick maths:
    M = (a_g * D²) / (4 * G)    where G = 6.67E-11 in SI units.
    V = (PI / 6) * D³
  rho = M / V = (3 * a_g) / (2 * PI * G * D)


Mars: rho = (3 * 0.38 * 9.81) / (2 * PI * 6.67E-11 * 6.8E6) = 3.9 g/cm³.
Tau Ceti VII: rho = (3 * 0.91 * 9.81) / (2 * PI * 6.67E-11 * 29E6) = 2.2 g/cm³.

Note that the gravity isn't actually the same as Mars (0.91 Gs vs 0.38 Gs), but if it were the density would still be a comfortable 0.92 g/cm³.

You can also check the density in SM mode by selecting the body and clocking the "Modify Body" button in the lower-right panel. I'm fairly sure this density is used to compute the gravity, not vice-versa, so you can be assured that the range of values is reasonably realistic. 

[jamac41]

By my calculations, the planet in question appears to have a density of 2. 2 g/cm³ which seems reasonable.  Mars is 3. 9 g/cm³ for comparison.

Quick maths:
    M = (a_g * D²) / (4 * G)    where G = 6. 67E-11 in SI units.
    V = (PI / 6) * D³
  rho = M / V = (3 * a_g) / (2 * PI * G * D)


Mars: rho = (3 * 0. 38 * 9. 81) / (2 * PI * 6. 67E-11 * 6. 8E6) = 3. 9 g/cm³.
Tau Ceti VII: rho = (3 * 0. 91 * 9. 81) / (2 * PI * 6. 67E-11 * 29E6) = 2. 2 g/cm³.

Note that the gravity isn't actually the same as Mars (0. 91 Gs vs 0. 38 Gs), but if it were the density would still be a comfortable 0. 92 g/cm³.

You can also check the density in SM mode by selecting the body and clocking the "Modify Body" button in the lower-right panel.  I'm fairly sure this density is used to compute the gravity, not vice-versa, so you can be assured that the range of values is reasonably realistic.   

You're right, I was meaning Venus and typing too late at night.  And its density is indeed . 4 of Earth's, which is 2. 2g/cm³ as you say.  I think I was just thrown off a bit by the 62b max population, which is about three times higher than the next largest I've seen, at a lower gravity than Earth's.

[Sven]

"2. 1. 1 Function #917: Value was either too large or too small for an Int32. "

I think I nailed down that one. The problem was a civilian transport delivering a Massdriver to 2017 MBT. I think the issue was , the displaying the ETA on the Solar system view of that civilian transport. Since that one displayed "error", and on every increment threw the error. To me at least it would make sense to have that integer overflow on every update of the ETA number of all the ships in system.