On Sunday night, the gibbous moon appears low in the southeastern sky, near the bright star Spica. The two are in the zodiacal constellation Virgo, a constellation we associate with summer.

The moon is two days from full.

Spica is a summer favorite, the principal star in Virgo. Spica has a distinct blueish tint. It is gigantic and is actually more than one star. Were Spica to replace our own star, the Earth would be toast. Spica is so far from us it takes light 262 years to reach us, which means that the light we see is older than our country. It is also so far away, astronomers can only see one point of light. By measuring the light from the star with spectroscopes and using advanced technology, they’ve determined that there are at least two big stars caught together. Spica is a very brilliant double star, a binary star.

Astronomers know there are at least two giant stars caught in a very tight orbit. Each star is bigger than our own sun and the forces being played out by these two bright stars is complex, almost inconceivable.

The two stars orbit each other in only four days. It takes our Earth one year to complete its orbit around the Sun. Imagine the scope of these two giant stars caught in a quicker dance, farther apart from each other than we are from the sun. And there is now new evidence to suggest that Spica may be as many as three stars caught together.