R Leonis

If you go out into the garden and look up towards the north the most conspicuous constellation you see is Leo the lion. Mainly because of the reversed-question-mark pattern, Leo cannot be mistaken for any other constellation. And Regulus, the brightest star in Leo, is very obvious, even from the city.

This months variable is R Leo, a Mira type variable not far from Regulus. It gets to about 5th magnitude at its brightest and can easily be followed in a small telescope, or even with a pair of binoculars. This type of variable can be observed about once a week and will soon show the sinusoidal-type light curve typical of Miras.

Why observe these stars? Because their light curves seem to vary with every cycle and astronomers could do with another couple of hundred years of observations to work out what they are doing. So your observations could help solve the mystery.

Brian Fraser