So, the curved shape that made the question mark could be a tidal tail. The image taken by the telescope, released last month, shows Herbig-Haro 46/47, which is a star forming cloud, Caplan explained.

Experts in the UK say the question mark is perhaps less cryptic than it appears - and could simply show two merging galaxies, with one being stretched out by the gravity of the other.

No doubt it will get to the bottom of the question mark mystery very soon. Edited by: Clare Roth. Zulfikar Abbany Senior editor fascinated by space, AI and the mind, and how science touches people.