Scientists have successfully taken first ever picture of the shadow of a zwart gat providing direct observation of its immediate environment
Image taken from “EHTC, Akiyama K et al 2019, ‘First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Zwart Gat‘, The Astrophysical Journal Letters, Vol. 875, no. L1.”
De super-massieve zwarte gaten were first predicted by Einstein in 1915 in his General Theory of Relativity when he showed gravity bends light. There have been many developments since then but never any direct evidence. Scientists were only able to detect them indirectly. The first real picture of the shadow of a super massive zwart gat has now been captured providing first direct evidence of their presence, thanks to ”The Event Horizon Telescoop Samenwerking".
De zwarte gaten are extremely compressed mass in a very small region. Its gravity is so high that nothing at all escapes if gets too close to its boundary. The Event Horizon is the boundary around the zwart gat that marks what is inside and what is outside. Once anything crosses this boundary, it gets swallowed and can never come out. Zwarte gaten swallow all light therefore they are invisible and cannot be seen or pictured.
The intense gravity of zwart gat attracts and pulls interstellar gas onto itself faster and faster. This heats up the gas immensely and light radiation is emitted. These emissions are warped into a circular ring by the gravity of the zwart gat.
A zwart gat itself is invisible but its shadow against super-heated gas cloud around it could be pictured.
Black hole’s presence couldn’t be directly observed uptill now mainly due to the fact that zwarte gaten are extremely small targets for the available radio telescopes which were not capable enough to observe their event horizon. Observing zwarte gaten directly needed building an ingenious telescope virtually the size of Earth.
It took about a decade to organise a network of telescopes called the ”Event Horizon Telescope” spanning the face of the Earth which combined eight separate telescopes in Mexico, Arizona, Hawaii, Chile and South Pole. All eight dishes of the telescope needed to be linked and pointed towards the zwart gat at exactly the same time. The signals received by the telescopes were combined by a correlator (a super computer) to give an image of the event horizon of the zwart gat.
Het succes van dit experiment is een belangrijke doorbraak in de astronomie.
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{U kunt de originele onderzoekspaper lezen door op de DOI-link hieronder in de lijst met geciteerde bron(nen) te klikken}
Bron (nen)
1. EHTC, Akiyama K et al 2019. Eerste resultaten van de M87 Event Horizon-telescoop. I. De schaduw van het superzware zwarte gat'. De astrofysische journaalbrieven, 875 (L1) https://doi.org/10.3847/2041-8213/ab0ec7
2. Max Planck Instituut voor Radioastronomie, 2019. Eerste foto ooit van een zwart gat. Opgehaald van https://www.mpg.de/13337404/first-ever-picture-of-black-hole
3. BlackHoleCam, 2019. DE GEBEURTENISHORIZON VAN ZWARTE GATEN AFBEELDEN, opgehaald uit https://blackholecam.org/
4. Europese Commissie – Persbericht, 2019. Door de EU gefinancierde wetenschappers onthullen de allereerste afbeelding van een zwart gat. Opgehaald van http://europa.eu/rapid/press-release_IP-19-2053_en.htm
