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The first image of a black hole, released in 2019, was made by linking radio telescopes around the world so that they worked as one telescope the size of Earth.

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The black hole lies at the centre of the galaxy M87, about 55 million light years away, and has about 6.5 billion times the mass of the Sun. A black hole gives off no light of its own; the picture shows a ring of glowing hot gas around its dark shadow. In April 2017 eight radio telescopes at six sites, from Hawaii and Chile to Spain and the South Pole, observed it at the same moments, each timed by an atomic clock. The recordings were too large to send over the internet, so hard drives were flown to computing centres in the United States and Germany to be combined. The Event Horizon Telescope team of more than 200 scientists released the result on 10 April 2019, and in 2022 an image of Sagittarius A*, the black hole at the centre of our own galaxy.

Türkçe oku
2019'da yayımlanan ilk kara delik görüntüsü, dünyanın dört bir yanındaki radyo teleskoplarını Dünya büyüklüğünde tek bir teleskop gibi birlikte çalıştırarak elde edildi.

Kara delik, yaklaşık 55 milyon ışık yılı uzaklıktaki M87 galaksisinin merkezindedir ve kütlesi Güneş'inkinin yaklaşık 6,5 milyar katıdır. Kara delikler kendileri ışık yaymaz; görüntüde, karanlık gölgesinin çevresinde parlayan sıcak gazdan bir halka görülür. Nisan 2017'de, Hawaii'den Şili'ye, İspanya'dan Güney Kutbu'na altı ayrı yerdeki sekiz radyo teleskobu, her biri bir atom saatiyle zamanlanarak aynı anlarda bu kara deliği gözledi. Kayıtlar internetten gönderilemeyecek kadar büyüktü; bu yüzden sabit diskler, verilerin birleştirileceği ABD ve Almanya'daki hesaplama merkezlerine uçakla taşındı. Olay Ufku Teleskobu'nun 200'ü aşkın bilim insanından oluşan ekibi sonucu 10 Nisan 2019'da açıkladı. Ekip 2022'de de kendi galaksimizin merkezindeki kara delik Sagittarius A*'nın görüntüsünü yayımladı.

Sources and further reading

Background reading: Event Horizon Telescope
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