Spring Triangle

The Spring Triangle with Arcturus, Spica, and Regulus plus (May 2017) Jupiter and, "incidentally", the Moon. The line between Spica and Regulus nearly represents the ecliptic, the path of the sun and planets. Arcturus and Spica are found along an arcing path off the handle of the big dipper, while Regulus can also be found from the big dipper by pointing from down from the third and fourth dipper stars.

The Spring Triangle is an astronomical asterism involving an imaginary triangle drawn upon the celestial sphere, with its defining vertices at Arcturus, Spica, and Regulus. This triangle connects the constellations of Boötes, Virgo, and Leo. It is visible rising in the south eastern sky of the northern hemisphere between March and May.

George Lovi of Sky & Telescope magazine had a slightly different Spring triangle, including the tail of Leo, Denebola, instead of Regulus. Denebola is dimmer, but the triangle is more nearly equilateral.

These stars form parts of a larger Spring asterism called the Great Diamond together with Cor Caroli.

The stars of the Spring Triangle

Constellation	Name	Apparent magnitude	Luminosity (× solar)	Spectral type	Distance (light years)
Boötes	Arcturus	−0.04	176	K1.5	36.7
Virgo	Spica	1.04	12100	B1	260
Leo	Regulus	1.35	288	B7	79.3
	Denebola	2.11	15	A3	35.9

See also

• Summer Triangle
• Winter Triangle
• Northern Cross

External links

• Lions in the Sky and other Spring Treasures
• The Spring Triangle Shows Denebola instead of Regulus in the spring triangle