Herschel Space Observatory Spies Baby Stars, Some of the Youngest Ever Seen

Young stars aren't always easy to see. They're usually enveloped by dense gas and dust. Now, though, the Herschel space observatory has finally revealed images that show some of the youngest stars ever seen.

Very young stars are called protostars, and are formed after the gravitational collapse of massive clouds of gas and dust. The changeover from stray, cool gas to the ball of super-hot plasma is relatively quick when speaking in the terms of the universe--it lasts only a few hundred thousand years. Yet finding these young stars during their earliest, most short-lived and dimmest stage usually poses a problem for astronomers.

In fact, for years scientists have investigated the stellar nursery in the Orion Molecular Cloud Complex. This cosmic site is a vast collection of star-forming clouds. Before now, though, astronomers had not seen the protostars located in the region. Now, the Herschel space observatory has revealed 15 protostars during a survey of the large star formation.

"Previous studies have missed the densest, youngest and potentially most extreme and cold protostars in Orion," said Amelia Stutz, lead author of the paper detailing the findings, in a press release. "These sources may be able to help us better understand how the process of star formation proceeds at the very earliest stages, when most of the stellar mass is built up and physical conditions are hardest to observe."

So how did Herschel spy the stars? It used far-infrared, also known as long-wavelength, light. This light can shine through even dense clouds, such as the ones that form around the new stars and which block out higher-energy, shorter wavelengths--including the light that our own eyes can see. Of the 15 newly discovered protostars, 11 of them possess very red colors. This means that their light output trends toward the low-energy end of the electromagnetic spectrum and that they're still embedded in their gaseous envelopes. Essentially, they're some of the youngest stars ever seen since they only spend about 25,000 years in this phase of their development.

"With these recent findings, we add an important missing photo to the family album of stellar development," said Glenn Wahlgren, Herschel Program Scientist, in a press release. "Herschel has allowed us to study stars in their infancy."

The details of these findings are published in The Astrophysical Journal.