                        Astronomy Picture of the Day

    Discover the cosmos! Each day a different image or photograph of our
      fascinating universe is featured, along with a brief explanation
                    written by a professional astronomer.

                              2023 September 19
     Two jets are seen in red and blue moving out from a central object
    shroueded by a diffuse dark brown. The rest of the frame is dark but
   with an few bright stars. Please see the explanation for more detailed
                                information.

                      HH 211: Jets from a Forming Star
       Credit: NASA, ESA, CSA, Webb; Processing: Tom Ray (DIAS Dublin)

   Explanation: Do stars always create jets as they form? No one is sure.
   As a gas cloud gravitationally contracts, it forms a disk that can spin
   too fast to continue contracting into a protostar. Theorists
   hypothesize that this spin can be reduced by expelling jets. This
   speculation coincides with known Herbig-Haro (HH) objects, young
   stellar objects seen to emit jets -- sometimes in spectacular fashion.
   Pictured is Herbig-Haro 211, a young star in formation recently imaged
   by the Webb Space Telescope (JWST) in infrared light and in great
   detail. Along with the two narrow beams of particles, red shock waves
   can be seen as the outflows impact existing interstellar gas. The jets
   of HH 221 will likely change shape as they brighten and fade over the
   next 100,000 years, as research into the details of star formation
   continues.

                 Tomorrow's picture: another star's planets
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