It is being said that the planet Venus could be mistaken for the Shawwaal moon.

Answer

In terms of the Shariah the Venus notice is drivel. It is incumbent to go for moonsighting at the end of the 29th day regardless of the age of the moon, even if the moon is one hour old. Confirmation of a sighting depends on Witnesses who have seen the hilaal. If the witnesses say that they have seen the moon, and the astronomers claim it to be the planet Venus, the claim of the latter will be rejected. The hukm will be on the basis of the testification of Aadil witnesses. All other methods are rejected.