Free Astronomy Magazine May-June 2021

30 MAY-JUNE 2021 ASTRO PUBLISHING How to measure the relativistic jet of M87 T his work describes spatial measurements made of the plasma jet emanating from the nucleus of the galaxy M87 and based on ob- servations performed at the La Laguna Astronomical Observatory (OLA, Granada, Spain). With this work, apart from our interest in the study itself, we want to demonstrate that it is possible to undertake “ap- parently inaccessible” astronomical investigations and calculations with the aid of typical amateur in- struments, with both telescope diameters and focal lengths far below those we find in professional ob- servatories, but which nevertheless give good re- sults when we are able to exploit the potential of our team for collecting and processing data. The calculations we carried out to obtain the dimen- sions of the M87 jet are not complex; the main dif- ficulty in this study was the isolation of the jet from the great brightness of the galaxy’s core. Given the resolving power of the instruments used, there is a higher degree of uncertainty in the values we have obtained compared to result one might obtain by using higher-resolution equipment and more elab- orate calculation techniques. However, as we shall see, our results are consistent with those considered to be the “established values” from observations with professional telescopes, including the Hubble Space Telescope (HST). by Aniceto Porcel & Miguel Sánchez revised by Damian G. Allis NASA Solar System Ambassador