Regulus

Where the name comes from

Regulus is Latin for the little king, a name given by Copernicus, though older Greek and Arabic names for it also carried the sense of kingly. It marks the heart of Leo, the lion, and sits at the base of a backwards question mark of stars called the Sickle.

The one the Moon keeps brushing past

Regulus lies almost exactly on the ecliptic, the line the Sun, Moon and planets follow across the sky. That makes it the bright star they pass closest to, so you will often catch the Moon sitting right beside it. Like a few other fast-spinning stars, Regulus whirls so quickly that it is flattened into an oval rather than a sphere.

How to find it

Regulus is the bright white star at the bottom of the Sickle of Leo, best on spring evenings from the northern hemisphere and visible from almost everywhere on Earth. It is the faintest of the first magnitude stars, about magnitude 1.4 in the catalogue Hali uses, but it is easy to spot because nothing else nearby is as bright. In some years the Moon passes directly in front of it, and on rare occasions a planet does too. Venus covered it in 1959, the last time a planet hid Regulus.

A star crossing a sign line

By Hali’s 2026 star positions Regulus sits at 0 degrees of the sign Virgo, and the Sun reaches it around 23 August each year, right at the changeover from Leo season to Virgo season. For the last two thousand years or so it sat in the sign Leo. At Hali’s measured precession rate it crossed into Virgo around 2012 and will stay in that sign for more than two thousand years. Some astrologers mark the crossing as the end of an era, which is a big reading of a fraction of a degree.

Regulus in a chart

Ptolemy gave Regulus the nature of Mars and Jupiter, and it is one of the fifteen Behenian stars of medieval astrology. Modern books call it one of the four royal stars of Persia, with Aldebaran, Antares and Fomalhaut, a grouping whose ancient source is uncertain. Astrologers who use fixed stars read a planet or angle within about a degree of Regulus as a mark of leadership and success, with a warning that it lasts only while the person stays generous and fair.

Common confusions

Regulus is the heart of the lion, not its head. The head and mane are the curve of the Sickle above it. It is also the brightest star in Leo, so if you can find Regulus you can find the whole lion.