By Reina Reyes

Some people consult the alignment of the stars to learn about their fate in love. But this is astronomy, not astrology. Here, we shall take a look at the lives of stars and see what they can teach us about love and relationships here on Earth. Warning: relationship advice to follow, with a cosmic twist.

Are you single or in a relationship? Our Sun is a single parent, with eight grown children— including Earth, the special middle child. Decades ago, it was hypothesized that the Sun had a companion, dubbed “Nemesis”, blamed to have caused past mass extinctions. Our telescopes have since surveyed the scene, but found no one.

Most stars do have companions. When we look at the sky with our telescopes, we find double stars—pairs of stars next to one another. They seem close, but looks can be deceiving. Some double stars are actually light-years apart, with one much farther away than the other— they just happen to lie along the same line of sight from Earth. These so-called optical double stars only appear to be together, but when you look closer, there is no real connection.

Are you in a close relationship, or one that only appears so?

Luckily, many double stars are actual binary star systems—two companion stars locked in a gravitational dance, orbiting around a common center of mass. This dance goes on for millions or billions of years, sending gravitational waves rippling out across space-time.

fig1
Binary stars in mutual gravitational embrace

There are three kinds of binary star systems, depending on how far apart the two stars are. Let’s take each one in turn, and ask: Which kind of binary system are you in? Which kind would you like to be in?

Two become one: Contact binaries

The two stars in a binary can be so close together they literally share a common atmosphere. This is, however, a highly unstable situation— it cannot last forever. In one scenario, friction caused by the smaller star orbiting around the atmosphere of the giant star can splash the atmosphere right off, much like stirring up water in a small pool will cause it to splash out. What is left is the naked core—another type of star called a white dwarf. Over time, the two stars will merge and form a single bigger star. The two stars that came into contact eventually become one.

fig2
Contact binaries are so close they share a common atmosphere.

Too close for comfort

Now, what if the stars are not touching one another, but are still close enough to be in each other’s gravitational space? Things get more interesting and potentially explosive! An extremely dense white dwarf cannibalizes the outer envelopes of its companion red giant. The captured gas forms a hot accretion disk around the star, and eventually makes its way to the surface. The white dwarf gains mass, but it can only take on so much. If it reaches a mass forty percent more than the mass of the Sun, it will not be able to support itself against gravity. The star undergoes catastrophic collapse and goes—BOOM!—supernova, in the process, blowing up its companion star into smithereens. 

Are you in a relationship in which one partner is losing his or her identity to the other? Is this relationship potentially destructive to one partner or both? I'd quickly get out of there—at warp speed—before the whole thing explodes!

fig3
A red giant loses its mass to a companion white dwarf in a semi-detached binary system.

Close, but not too close

When two stars have a healthy distance from one another, they can keep going around in this stable orbit for essentially forever #mayforever.  Moreover, they can also harbor planets, which are heated up by their combined warmth. These so-called circumbinary planets, first dreamed up in science fictionlike Tatooine in Star Wars  have now been discovered by NASA's Kepler space telescope. Together, the suns, planets, and moons make a happy family in mutual gravitational embrace.

Are you in a long-term relationship stable enough to sustain small dependents? Can you keep yourselves in each other's orbits, as long as you all shall live? 

fig4
An artist's impression of double stars as seen in the sky from the moon of one of its planets.

Are you in a binary system? Do you want to be in one? Whichever stage you are in—I wish you love, light, and a happy heart’s day, every day of your orbit!

"A version of this essay has appeard previously as "Love May Be How Stars Align" in the Business Mirror."  

garybc 20160308 RevCam 010 crop 2Reina Reyes obtained her Ph.D. in Astrophysics from Princeton University in 2011. She is currently teaches at Ateneo de Manila University and Rizal Technological University in Manila, Philippines.