S4E56
    Dan

    Welcome to The Cosmic Savannah with Dr Daniel Cunnama

    Jacinta

    and Dr Jacinta Delhaize. Each episode, we'll be giving you a behind-the-scenes look at world-class astronomy and astrophysics happening under African skies.

    Dan

    Let us introduce you to the people involved, the technology we use, the exciting work we do, and the fascinating discoveries we make.

    Jacinta

    Sit back and relax as we take you on a safari through the skies.

    Dan

    Welcome to episode 56, where we have some exciting news.

    Jacinta

    Hi everyone. Yeah. Sorry. This episode's been slightly delayed by COVID, as many things are these days, so I'm sure you'll forgive us. But yeah, sorry about that. But in the meantime, of course, there has been some extremely exciting news, which I'm sure many of you have already heard about. Of course, the Event Horizon Telescope put out a new press release.

    So you may remember in 2019, the EHT telescope took its first picture of a supermassive black hole. That was M87*. And that's a supermassive black hole at a galaxy sort of outside of our own galaxy - a different galaxy. And then when Dan and I heard that there was going to be another announcement from the EHT, Dan was like, "Oh, it might be Sagittarius A*. SagA*!"

    Dan

    So, yeah. We are joined by Dr Iniyan Natarajan, who is a postdoctoral fellow at the University of Witwatersrand in Johannesburg. And he'll be telling us a little bit about the discovery and his involvement and some exciting news in terms of Africa's involvement going forward.

    But first up, I think we should just chat a little bit about the discovery, not taking too much away from Iniyan. Super cool. I mean the second black hole we've imaged. First one M87*, as you've mentioned. And now we've got a nice selfie, I guess, of our own black hole.

    Jacinta

    Yes, just so cool. Like, ah, it's so exciting! For years, we've been telling people... yeah, no, there is really a supermassive black hole at the centre of the Milky Way. We know it's there. We've seen indirect evidence of this by other stars kind of orbiting around nothingness - something that looks blank. And, you know, studying those orbits, we know that it has to be of a certain mass and the fact that we don't see it means it has to be a supermassive black hole, based on the mass. But it's very, very, very hard to make an actual image of it. Iniyan will go into detail about why that is. But yeah, I guess examples online have said it's kind of like taking a picture of a toddler that keeps moving really, really fast. It's very difficult.

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