3
$\begingroup$

On the image of the M87 black hole released today by the Event Horizon Telescope team, which direction points towards the jet? Is it on the brighter side of the ring?

To resolve ambiguity, I'm talking about the main observed jet, not the fainter counterjet.

$\endgroup$

1 Answer 1

5
$\begingroup$

The jet is projected onto the image roughly in the E-W direction with the (main) jet coming towards us to the right of the black hole.

The brightening in the ring is perpendicular to this. It is probably caused by the spin of the black hole (aligned with the jet), which drags emitting material around and Doppler boosts the emission seen to the south.

This picture is from the fifth event horizon telescope paper published today. The jet is E-W (actually, I believe it is at PA=288 degrees, so rotated 18 degrees anticlockwise) and the black hole spin axis (indicated with the black arrows) is projected at the same PA and into the screen (the two left hand plots).

Event Horizon black hole orientation

$\endgroup$

You must log in to answer this question.