are you questioning whether it's a baby or whether it's new? or whether it's theirs?
Or perhaps what area of expertise in astronomy the baby has.
That would be too obvious.
Neutron stars? If it's a mix of asteroids and galaxies? But of course, who knows exactly how the genes would work.
Suppose, even astronomy might be recessive. Eep!
Right, the baby will probably be into electional astrology instead of whatever nonsense the parents are in to.