The Two Scientific Ways We Can Improve Our Images Of Event Horizons
“By properly equipping and calibrating each participating telescope, the resolution sharpens, replacing an individual telescope’s diameter with the array’s maximum separation distance. At the Event Horizon Telescope’s maximum baseline and wavelength capabilities, it will attain resolutions of ~15 μas: a 50% improvement over the first observations. Currently limited to 345 GHz, we could strive for higher radio frequencies like 1-to-1.6 THz, progressing our resolution to just ~3-to-5 μas. But the greatest enhancement would come from extending our radio telescope array into space.”
It’s absolutely incredible that we’ve got our first image of a black hole’s event horizon, and a monumental achievement for science. But like all scientists, opening the door to a new “first” only increases our drive to surpass what we’ve accomplished and improve our capabilities beyond anything we’ve achieved before. For an event horizon, that means higher resolutions and sharper images, and we have two scientific ways to get there: probing higher frequencies and extending the length of our baseline to beyond the limits of planet Earth.
Both of these are technologically possible, and will likely, over the coming years and decades, be how we push past our scientific limits. Come learn how.
Ask Ethan: How Does Very-Long-Baseline Interferometry Allow Us To Image A Black Hole?
“[The Event Horizon Telescope] uses VLBI. So what is interferometry and how was it employed by [the Event Horizon Telescope]? Seems like it was a key ingredient in producing the image of M87 but I have no idea how or why. Care to elucidate?”
If it were easy to network radio telescopes together across the world, we’d have produced an image of a black hole’s event horizon long ago. Well, it’s not easy at all, but it is at least possible! The technique that enabled it is known as VLBI: very-long-baseline interferometry. But there are some critical steps that aren’t very obvious that need to happen in order for this method to succeed. Remarkably, we learned how to do it and have successfully employed it, and the Event Horizon Telescope marks the first time we’ve ever been able to get an image with a telescope that’s effectively the size of planet Earth!
Come get the incredible science behind how the technique of VLBI enabled the Event Horizon Telescope to construct the first-ever image of a black hole’s event horizon!