Star Birth
If you’ve been a reader of this site for long, you probably wondered when I’d get to starbirth in this list of seven cosmic wonders. Wait no longer—here it is! Starbirth is one of the great recycling mechanisms of the cosmos. It takes material that is floating around in interstellar space and, under the right conditions, coalesces that material into a star. The process is incredibly long compared to human life spans. Our own star began forming some 4.6 billion years ago. It will live for another 5 billion years and eventually evolve to a white dwarf star. Before it does, the Sun will swell up to become a giant star, shed most of its mass, and then slowly cool and shrink. All that material that it sheds will populate the interstellar medium, perhaps becoming part of new stars in the distant future. Supernova explosions also return elements to space, and those too will become part of new stars and planets.
Regions of starbirth are nearly everywhere we look in our own galaxy and in countless other galaxies, too. Astronomers study them in just about every wavelength of light possible, although infrared-enabled observatories and instruments have the best chance of peeking into the stellar creches to watch the process of stars being born.
The closest starbirth region that most of us have heard about is the Orion Nebula, some 1,500 light-years away in the constellation Orion. If you look closely at the blow-up of this image (far left), you’ll see swirls of clouds, and what look like jets emanating from some of the new stars. Newborn stars are chaotic, and they sculpt their birth nests as they form. They also light up their surroundings, creating reflection nebulae—clouds of gas and dust that glow in the reflected light. However, those clouds also give off infrared light because they’re being heated by the nearby stars. So, I give you a glimpse into the mysterious realms of starbirth, a process that is itself one of the seven wonders of the universe.