Event Horizon Telescope – Capture the Edge of Light

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This artist’s impression depicts a rapidly spinning supermassive black hole surrounded by an accretion disc. This thin disc of rotating material consists of the leftovers of a Sun-like star which was ripped apart by the tidal forces of the black hole. Shocks in the colliding debris as well as heat generated in accretion led to a burst of light, resembling a supernova explosion.

Remember that awesome movie with Laurence Fishburne back in the 90’s called Event Horizon?  The one with the awesome ship and the crazy astrophysical spacetime drive reactor that made everyone basically kill themselves once they had seen what it had to show?

Yeah, there is nothing about that movie that really relates to this post, but damn, that was a great movie…

Now there is a project going on that is trying to capture the event horizon of a black hole — for those non-nerds out there, an event horizon is basically that “point of no return” where something as massive as a black hole has such gravitational pull that not even light can escape its gravitational force.  Watch the movie Interstellar, it does a pretty good job at explaining what this “event” really is and how it relates to spacetime.  Spacetime itself is a mathematical model — take all three of the dimensions that we know, and mix in the dimension of time (which is a single dimension as we know it), and you have spacetime.  Geometry, relative physics, spacetime, event horizons, black holes — all things that are far beyond my paygrade and relativistic understanding, and I think I’m pretty good at math.

What we do know, however, is that we don’t know about what an event horizon looks like, because there is no way to directly observe one — or a black hole.  Light inside of a black hole can’t escape, and light emitted from inside a black hole is thought to experience an elongation of the wavelength itself, causing constant red shift as it gets longer and longer…  remember that red wavelengths are the longest in our spectrum.  The gravity of a black hole literally stretches the wave apart.

This artist’s impression depicts a rapidly spinning supermassive black hole surrounded by an accretion disc. This thin disc of rotating material consists of the leftovers of a Sun-like star which was ripped apart by the tidal forces of the black hole. Shocks in the colliding debris as well as heat generated in accretion led to a burst of light, resembling a supernova explosion.

What’s awesome about all of this is that we really have no idea what the hell it is — it’s all completely mathematical.  We’ve not observed an event horizon, we can’t as of now even do so — but there is a project called the Event Horizon Telescope that is attempting through world scale technology (as in tech all over the globe) to analyze and interpret several data points to increase our understanding of this phenomena of the event horizon.  Way cooler than a movie, but scientifically very difficult.  From the Event Horizon Telescope page:

A long standing goal in astrophysics is to directly observe the immediate environment of a black hole with angular resolution comparable to the event horizon.  Such observations could lead to images of strong gravity effects that are expected near a black hole, and to the direct detection of dynamics near the black hole as matter orbits at near light speeds.  This capability would open a new window on the study of general relativity in the strong field regime, accretion and outflow processes at the edge of a black hole, the existence of event horizons, and fundamental black hole physics.

The EHT is an international collaboration that has formed to continue the steady long-term progress on improving the capability of Very Long Baseline Interferometry (VLBI) at short wavelengths in pursuit of this goal.  This technique of linking radio dishes across the globe to create an Earth-sized interferometer, has been used to measure the size of the emission regions of the two supermassive black holes with the largest apparent event horizons: SgrA* at the center of the Milky Way and M87 in the center of the Virgo A galaxy.  In both cases, the sizes match that of the predicted silhouette caused by the extreme lensing of light by the black hole.  Addition of key millimeter and submillimeter wavelength facilities at high altitude sites has now opened the possibility of imaging such features and sensing the dynamic evolution of black hole accretion.  The EHT project includes theoretical and simulation studies that are framing questions rooted at the black hole boundary that may soon be answered through observations.

By linking together existing telescopes using novel systems, the EHT leverages considerable global investment to create a fundamentally new instrument with angular resolving power that is the highest possible from the surface of the Earth.  Over the coming years, the international EHT team will mount observing campaigns of increasing resolving power and sensitivity, aiming to bring black holes into focus.

You can follow the Event Horizon Telescope on Facebook and Twitter at @ehtelescope.

Think about it — a black hole is so powerful that nothing can escape its gravitational pull, not even photons.

Here’s Matt to talk about just what happens at the event horizon — worth the watch, especially if you’re feeling mathematically nerdy:

Amazing concepts.  I always wonder in our lives what we will get to discover.

Some heavy brain lifting:

https://en.wikipedia.org/wiki/Three-dimensional_space
https://en.wikipedia.org/wiki/Event_horizon