                        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.

                                 2025 May 9
    An artist's illustration of what the surroundings of the supermassive
     black hole at the center of BL Lac is shown. A white jet protrudes
    horizontally toward the bottom of the image, emanating from a orange
   accretion disk surrounding a black hole. Please see the explanation for
                         more detailed information.

                       IXPE Explores a Black Hole Jet
                   Illustration Credit: NASA, Pablo Garcia

   Explanation: How do black holes create X-rays? Answering this
   long-standing question was significantly advanced recently with data
   taken by NASA’s IXPE satellite. X-rays cannot exit a black hole, but
   they can be created in the energetic environment nearby, in particular
   by a jet of particles moving outward. By observing X-ray light arriving
   from near the supermassive black hole at the center of galaxy BL Lac,
   called a blazar, it was discovered that these X-rays lacked significant
   polarization, which is expected when created more by energetic
   electrons than protons. In the featured artistic illustration, a
   powerful jet is depicted emanating from an orange-colored accretion
   disk circling the black hole. Understanding highly energetic processes
   across the universe helps humanity to understand similar processes that
   occur on or near our Earth.

              Put it All Together: Astronomy Puzzle of the Day
                    Tomorrow's picture: Yogi on Mars: 3D
     __________________________________________________________________

       Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
            NASA Official: Amber Straughn Specific rights apply.
                  NASA Web Privacy, Accessibility, Notices;
                      A service of: ASD at NASA / GSFC,
                           NASA Science Activation
                             & Michigan Tech. U.

