The latest result is 299,860 kilometres per second, with a probable error of perhaps 30 kilometres - that is, about the ten-thousandth part of the quantity itself.
From a series of measures of the angle between Jupiter's satellites and the planet, made in June and July 1794 and in August and September 1795, Schur finds the mass of Jupiter =I / Io 4 8.55 1.45, a result which accords well within the limits of its probable error with the received value of the mass derived from modern researches.
The probable error in neglecting any variation of specific heat is small, and we may calculate L from the values of Lo - (s - s') (To - T), where s - s' is about 0.5 calories.
This method has been very generally recommended, but it is really bad, because, although it diminishes the absolute magnitude of the correction, it greatly increases the uncertainty of it and therefore the probable error of the result.
For one or two of the more famous stars such as a Centauri the probable error is less than so oi"; but for others in the list it ranges up to X0.05".
