"Amazing! Well done Nasa! Send my love to the aliens," said Sir Paul McCartney, one of the two surviving Beatles.

Although Nasa have often transmitted music to astronauts in orbit, this is the first time that they have targeted deep space -- in this case, the North Star aka Polaris.

Polaris is situated 2.5 quadrillion miles away -- or 2,500,000,000,000,000,000,000,000 miles away if you prefer.

The song will take 431 years to reach Polaris -- arriving in the year 2439.

This historic transmission is intended to celebrate a number of anniversaries.

2008 sees the 50th anniversary of the formation of Nasa.

This year is also the 50th anniversary of key events surrounding the formation of The Beatles.

The first ever US satellite -- Explorer 1 -- was launched into space 50 years ago.

And February 4th is the 40th anniversary of the Beatles recording Across The Universe at the legendary Abbey Road studios.

Transmission will commence from the Jet Propulsion Laboratory in Pasadena, California, where Explorer 1 was built and launched 50 years ago.

The song will be beamed to Nasa's Deep Space Communications Complex in Madrid, Spain.

From there, it will be sent into space via a 70-metre diameter DSS-63 antenna.

This antenna is usually used to communicate with deep space spacecraft, such as Voyager and Cassini.

Across The Universe was reputedly one of John Lennon’s favourite songs.

Although credited to Lennon-McCartney, the song was mostly written by Lennon.

"I see that this is the beginning of the new age in which we will communicate with billions of planets across the universe," said Yoko Ono, Lennon's widow.