VENUS and Jupiter will appear side by side after sunset tonight as their paths appear to cross in the night sky.
Amateur astronomers have been following the planets as they appear just a couple of degrees apart in the sky.
They reached their closest point last night and will be clearly visible again tonight just a couple of degrees apart in the sky to the west-southwest, before drifting apart as the week goes on.
Although it is not unusual for two planets to appear to pass by one another, there is excitement surrounding the spectacle because Venus and Jupiter are two of the brightest planets in the solar system.
Tonight they will be so close that the gap between them will appear from Earth to be about the width of two fingers held at arms length.
Their brightness is such that they will be visible to the naked eye from across the country immediately after sunset, and will be clearly distinguishable even to people with no experience of astronomy.
Robert Massey, of the Royal Astronomical Society, said: "The two being so close together will be beautiful. Last night they looked like two beacons.
"They will be unmistakable because both are really bright, and they will be visible before you can see any stars which is the real giveaway.
"Look outside to the west at about seven o'clock and unless you are standing beside a skyscraper you won't be able to miss them. It would not surprise me for one second if we got people reporting U.F.O. sightings because they are so bright."
The paths of the planets appear to cross because their orbits are briefly aligned, even though they are vast distances apart in reality.
The planets will be fairly high in the sky about 40 degrees above the horizon with Venus, the brighter of the two, positioned slightly above and to the right.
After tonight the planets will drift further apart, though Jupiter will remain visible for at least two more weeks.
The astronomical event comes a week after Mars made its closest pass of Earth in more than two years, and three months before the transit of Venus, the most eagerly anticipated stargazing event of 2012 when the planet will appear from some places to pass in front of the Sun.