Tag Archives: Jets

Young-star Jets Experience a Time Delay

Spitzer Space Telescope Studies Phenomenon in Depth

Two views of the same newborn star, visible light at left and infrared at right. Credit: NASA/JPL-Caltech

Astronomers have discovered that two symmetrical jets shooting away from opposite sides of a blossoming star are experiencing a time delay: knots of gas and dust from one jet blast off four-and-a-half years later than identical knots from the other jet. In this split image, the jets appear in greenish hues (right image inset) emanating from either side of the star.

The finding, which required the infrared vision of NASA’s Spitzer Space Telescope, gives astronomers new clues about how jets are produced around forming stars, including those resembling our Sun when it was young.

“More studies are needed to determine if other jets have time delays,” said Alberto Noriega-Crespo of NASA’s Spitzer Science Center at the California Institute of Technology in Pasadena, who is a co-author of the new study that was published in the April 1 issue of Astrophysical Journal Letters. “Now we know that in at least one case, there appears to be a delay, which tells us that some sort of communication may be going on between the jets that takes time to occur.”

Jets are an active phase in a young star’s life. A star begins as a collapsing, roundish cloud of gas and dust. By ejecting supersonic jets of gas, the cloud slows down its spinning. As material falls onto the growing star, it develops a surrounding disk of swirling material and twin jets that shoot off from above and below the disk, like a spinning top.

Once the star ignites and shines with starlight, the jets will die off and the disk will thin out. Ultimately, planets may clump together out of material left in the spinning disk. For more details on this new finding, visit this NASA-related site about the discovery.