A giant leap for mankind in science

Editor's note: Event Horizon Telescope researchers released the first-ever image of a black hole on Wednesday evening. The extraordinary scientific feat was accomplished by a team of more than 200 researchers from across the world, including 16 from the Chinese mainland. Three experts share their views on the breakthrough achievement with China Daily's Zhang Zhouxiang. Excerpts follow:

A 'doughnut' prepared with extreme difficulty

After seeing the photograph of the black hole, some people on social media networks jokingly said it looks like a "doughnut".