BBC on the conjunction
Jupiter and Venus will be visible to the naked eye close together in the sky before dawn on Monday.
The planets will appear in conjunction in the south-east, just above the horizon, and may appear to look like one bright star.
In the UK, the best viewing time will be 40 minutes before sunrise.
Jupiter's four Galilean moons will also be visible to those with a telescope. Clear skies are needed - and forecast for much of England and Wales.