Corona Effect

Hello @Brice26568305xbr2,

Thanks for reaching out. I hope the suggestions shared by Monika helped resolve the problem.

Feel free to reach out if you have more questions or need assistance. We'd be happy to help.

Thanks,

Anubhav

Draw some dots

Free transform

Make a couple of different ones if you like, makes this look better

Colour them for the color version

Make art brushes. The black one needs to be colorization method: tints

Draw lines:

Select all, Object > Transform, > Transform each and scale them randomly

Set the fill to black 

Draw a red (or other unused color) filled circle

Select the lines and the red circle and Pathfinder panel: Outline

Select one of the red lines with direct selection tool and then Select > Same > Stroke color

Delete

Apply the art brush to the black lines and color their strokes whatever color you like.

For some of them you need to reverse direction of either the path or the brush.