• Question: How are pictures of back holes taken ?

    Asked by anon-220957 on 26 Jun 2019.
    • Photo: Kaitlin Wade

      Kaitlin Wade answered on 26 Jun 2019:

      Great question. The most recent is probably the most famous, as that is the only real picture of a black hole we have ever seen:

      https://www.sciencenewsforstudents.org/article/black-hole-first-photo-event-horizon-telescope

      How this happened was a huge amount of collaboration and timing. Essentially what the scientists did was use as many of the large telescopes as possible, all over the world, and coordinated the timing of these telescopes to take a picture with what is essentially a massively long shutter speed – this collaboration was called the “Event Horizon”. In 2020, they’re planning on increasing the number of telescopes (in observatories) in the Event Horizon Collaboration to 11 so IMAGINE what amazing pictures they’ll be able to take next!!

    • Photo: Matthew Bareford

      Matthew Bareford answered on 26 Jun 2019:

      This is actually a really interesting point… black holes cannot actually be photographed….

      To explain, a black hole is where no light or matter can escape but in order to take an image/picture of something, you need light… thus it is impossible to take a picture/image of a black hole….

      What it is possible to do, is to take a picture of what is called the ‘accretion disc’ (the matter and things swirling around the outside of a black hole, which you can see on all the iconic images and the latest image of black holes). This disc will reflect light and so can be observed. What this does, is essentially give you this ‘void’ within the image/picture, essentially a hole and because no light = black colour, we get a ‘black hole’.

      I hope this makes sense?

    • Photo: Nina Rzechorzek

      Nina Rzechorzek answered on 26 Jun 2019:

      Great question! Essentially, using a collaboration of many telescopes collecting the largest data set ever to capture parts of the Event Horizon around the black hole (to use as a backdrop, so that a black thing can be seen on a black background). The gaps in the data were filled using algorithms in a process called ‘interferometry’. This 3 minute video explains it nicely:

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