How long does the protostar stage last for a star like our sun?

The Protostar Stage: When Our Sun Was Just a Baby

Ever wonder how stars like our Sun come to be? It’s a wild ride that starts way before they’re shining bright. Think of it as a stellar adolescence, a messy, formative period called the protostar stage. This is where stars are still in diapers, figuring things out, and it’s way longer than you might imagine.

So, how long does this awkward phase last for a star like our Sun? Well, buckle up, because we’re talking millions of years – roughly 10 million, give or take.

Let’s break it down. Star birth kicks off when a hefty chunk of gas and dust in space decides to collapse under its own weight. Imagine a cosmic snowball fight gone wrong, where one snowball gets so big it starts crushing everything around it. As this cloud shrinks, it heats up, and BAM! A protostar is born at the center. This little star-to-be keeps gobbling up material from the surrounding cloud, growing bigger and denser. It’s like a teenager hitting a growth spurt, constantly hungry.

The protostar stage is all about this feeding frenzy. Stuff from the cloud swirls around and eventually falls onto the protostar, often through a swirling disk. This “accretion,” as the scientists call it, is the protostar’s main energy source. It glows, but the surrounding dust hides most of the light. That’s why astronomers use special telescopes that see infrared and microwave light, which can pierce through the dust. It’s like using night-vision goggles to peek into a dark room.

Now, here’s the cool part: the length of this protostar phase depends a lot on how massive the star will eventually be. Big, beefy stars evolve super-fast, blasting through this stage in as little as a few thousand years. But smaller stars, like our Sun, take their sweet time. For a star the Sun’s size, this Kelvin-Helmholz timescale (basically, how long it takes to shrink and heat up) is around 30 million years. Imagine waiting 30 million years for your kid to finally move out of the house! A 30 Msun Protostar will collapse in

The protostar stage finally wraps up when the star’s core gets hot and dense enough to ignite stable hydrogen fusion. We’re talking about a scorching 10 million degrees Kelvin! That’s when the star officially “turns on” and joins the main sequence, the long and stable adulthood of a star’s life.

Keep in mind, that 10-million-year number is just a ballpark. The actual time can vary depending on things like how dense the original cloud was and how quickly the protostar slurped up material. Some studies suggest it could be as short as 100,000 years, or as long as a million.

Even though 10 million years sounds like forever, it’s just a blink of an eye compared to the Sun’s total lifespan of about 10 billion years. Our Sun is middle-aged right now, living its best life on the main sequence. So, the protostar phase is a quick but crucial chapter in a star’s story, setting the stage for its long, steady shine. It’s like the awkward teenage years that shape who you become – only on a cosmic scale!