In April, scientists hope to obtain the first photograph of a black hole using a series of radio-wave telescopes, known as the Event Horizon Telescope. Researchers will gather huge amounts of data that will either confirm or call into question the size and nature of black holes, as predicted by Einstein’s theory of relativity.
Photographing Sagittarius A*
Black holes, themselves, are too dark to be photographed. Previously, the otherwise unexplained orbit of certain stars around an invisible object at the center of the Milky Way Galaxy provided the primary evidence of the existence of the black hole known as Sagittarius A*. The Event Horizon Telescope will focus on this black hole, which has an event horizon diameter—or point of no return—of approximately 12.4 million miles.
This new telescope will attempt to capture images of the event horizon, a glowing ring of gas and dust that swirls with increasing speed as it’s ripped apart prior to entering the hole; the dark blob in the center will be the shadow cast on the vortex of the black hole where the debris is sucked in. The telescopes will capture over 10,000 laptops worth of data, which will be flown back on airplanes to MIT Haystack Observatory in Massachusetts before it’s compiled and analyzed. It could be the start of 2018 before scientists complete their work and release the images of the black hole.
Sagittarius A* is four million miles more massive than our sun, yet it appears the size of a pinprick on our sky because it’s 26,000 light years away, compared to the average distance of 150 million kilometers from which we orbit the sun. Thus, we would need a regular telescope the size of Earth to view Sagittarius A*, which is impractical.
Instead, the Event Horizon Telescope uses very-long-baseline interferometry (VLBI), which measures radio waves from a single object at an appointed time with a series of specialized telescopes spread across the globe. These radio receivers will view the black hole using a carefully chosen wavelength of 1.3mm (230GHz) to create the best opportunity of seeing through particles of dust in the area of the black hole; still, the success of the data recovery will depend largely on the weather, as moisture in the Earth’s atmosphere will also hamper the telescopes’ visibility.
The telescopes’ combined resolution should be 50 microarcseconds, which scientists say will provide them with the ability to see an object approximately the size of a grapefruit on the moon. With this precise technology, scientists are hoping to test their understanding of Einstein’s theory of relativity on a massive scale.
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