Mira type variable star R Aquilae (R Aql) now within binocular range

Variable star R Aquilae in the constellation Aquila is now towards the bright end of its range and currently easily visible with binoculars and small scopes. The star is a Mira type that normally fluctuates between magnitudes +5.5 and +12.0 over a period of 284 days. At it's brightest it can be glimpsed faintly with the naked eye. At it's faintest a minimum 80mm (3.1-inch) scope is required.

R Aql finder chart - pdf format - (credit - freestarcharts)

Mira stars are pulsating red giants nearing the end of their lives that vary by at least one magnitude over periods from 80 to over 1,000 days. Eventually they form planetary nebula with a white dwarf star left behind at the centre. In total at least 6,000 stars of this type are known.

Since every cycle is different they are interesting stars to follow. In addition, most vary over a considerably magnitude range and therefore the brightness changes are easily noticeable. For R Aquilae the period was over 300 days when first observed, but it has steadily declined since. From 1930 to 1950 it regularly peaked at mag. +5.0 or better before dimming down below mag. +12.5. Nowadays a range of +5.5 to +12.0 is more the norm.

Locating R Aqr is quite easy; it's positioned about 10 degrees west of first magnitude Altair (α Aqr - mag. +0.76). During June, the star can be seen towards the east around or just before midnight local time. R Aql shone at mag. +6.8 on June 4th and is predicted to brighten to about mag. +6.0 over the coming weeks. After that it will slowly fade but remain within binocular range for a few more months to come.

You can submit your magnitude estimates to the British Astronomical Association's Variable Star Section and the American Association of Variable Stars. The co-ordinates of R Aql are:- R.A. 19h 06m 22.25s Dec +08d 13m 48.0s