This is an x-ray image ASCA took on April 7 in the direction of M81. The image
clearly shows strong x-ray emission from the supernova in a location of some 3
arc minutes from the center of M81. This was the first time that x-rays were
detected from a supernova only 10 days after its explosion. This image also
shows that the x-ray telescope aboard ASCA can distinguish this supernova from a
binary-type x-ray source at a separation of about 1 arc minute.