Last year a great scientific endeavor called the Event Horizon Telescope (EHT) Collaboration released the first-ever image of a black hole to the world, located in the nearby radio galaxy M87. But recently the collaboration analyzed exciting new information from the EHT data taken from observations of the distant quasar called 3C 279. With unprecedented accuracy, the team running the new analyses traced the cosmic jets — moving at 99.5% of the speed of light — back to their mutual point of origin, where a violent and maddening radiation emission festers across the entire electromagnetic spectrum.
Quasar masking a monstrous black hole
Published in the journal Astronomy & Astrophysics, the goal of the study was a galaxy 5 billion light-years from the Earth, in the Virgo constellation, which scientists have qualified as a quasar because of an ultra-luminous energy source bursting and flickering from its center as unimaginable quantities of gas fall into a black hole. Called 3C 279, the target quasar surrounds a black hole roughly one billion times the mass of the Sun. Double-jets of hot plasma erupted from the black hole, and its surrounding disk system, at near-lightspeed velocities: the sum effect of a maelstrom of gigantic forces unleashed when matter falls helplessly into the black hole's extreme gravitational maw.
To catch the new image of the quasar, the EHT used a technique called very long baseline interferometry (VLBI). This method synchronizes and links radio dishes globally, and conjoins the network into one enormous virtual Earth-sized telescope. With this, the EHT is capable of resolving very small objects — 20 micro-arcseconds on the sky — equal to someone seeing an orange on the Moon's surface, from Earth. Worldwide data from all the EHT sites are transported into special supercomputers at MPIfR, and at MIT's Haystack Observatory, where the datasets are brought together. Conjoined, the experts then carefully calibrate and analyze the data, after which the EHT scientists produce images at ultimate Earth-bound opacity.
For 3C 270, the EHT is capable of measuring features smaller than one light-year in diameter, which helps astronomers follow the jet's path down to the accretion disk, where they interact in interesting ways. The recently-analyzed data shows that where the jet was expected to be straight, it has a twisted shape at its base, unveiling features perpendicular to the emitting jet, ones that might be the poles of the surrounding disk — in other words, where the jets shoot out like angry wasps from the core.
New images show phenomenal velocities near black hole
The new images chart a change in position over consecutive days, potentially due to the rotation of the accretion disk, and subsequent shredding and descent of the surrounding matter — all phenomena expected from mathematical simulations, but never seen before.
A researcher at the Max Planck Institute for Radio Astronomy's (MPIfR's) and also lead author of the paper Jae-Young Kim is at once enthusiastic and baffled: "We know that every time you open a new window to the Universe you can find something new. Here, where we expected to find the region where the jet forms by going to the sharpest image possible, we find a kind of perpendicular structure. This is like finding a very different shape by opening the smallest Matryoshka doll."
An astrophysicist who works in the Perimeter Institute explained: "For 3C 279, the combination of the transformative resolution of the EHT and new computational tools for interpreting its data have proved revelatory. What was a single radio 'core' is now resolved into two independent complexes. And they move — even on scales as small as light-months, the jet in 3C 279 is speeding toward us at more than 99.5% light speed!"
This scary and rapid motion causes the jet in 3C 279 to appear to move at roughly 20 times faster than the speed of light (emphasis on appearance). "This extraordinary optical illusion arises because the material is racing toward us, chasing down the very light it is emitting and making it appear to be moving faster than it is," said Dom Pesce, a postdoctoral fellow at the Center for Astrophysics in the Havard Smithsonian (CfA), to clarify the paradox. This unexpected geometry from this quasar means that there are traveling shocks, or instabilities in a bending, rotating jet, which could also lend clarification on observations of emissions at high energies, like gamma-rays — an epistemic object of great interest surrounding black holes.