Astronomers have said the "blood moon" that took place during the early hours of Tuesday 15 April 2014 was the first in a rare consecutive series of four, which will take place over the next two years.

The phenomenon is called a tetrad of lunar eclipses and although the event is rare, Nasa have stated that several tetrads will occur during this century alone.

Although one tetrad appeared in 2003 and 2004, there have been gaps of up to 500 years between the series of eclipses.

The current tetrad will take place in 2014 and 2015, with the second eclipse on 8 October, the third on 4 April and the final eclipse on 28 September. The next series of four will not happen again until 2032.

Fred Espenak, a Nasa astrophysicist, said it was "most unusual" that the current four eclipses of the moon will be "visible for all or parts of the USA".

He added: "During the 21st century, there are 8 sets of tetrads, so I would describe tetrads as a frequent occurrence in the current pattern of lunar eclipses.

"But this has not always been the case. During the three hundred year interval from 1600 to 1900, for instance, there were no tetrads at all."

A lunar eclipse occurs when the Earth is positioned directly between the Sun and the moon. According to Nasa, the Earth is surrounded with a fiery light which beams into its shadow, giving the moon an amber glow.

The moon's plane of orbit is slightly tilted, which is why a total eclipse does not occur every month.

Previous tetrads have coincided with significant religious and historic events and the current series of blood moons aligns the Jewish Passover, which takes place on 15 April, and feast of the Tabernacle in October.

In 1493, the first tetrad since the Middle Ages, saw the expulsion of Jews by the Catholic Spanish Inquisition, which rocked western Europe. The second coincided with the establishment of the State of Israel in 1949 and in 1967, one took place at the time of the Arab-Israeli Six-Day war.

Meanwhile, some Christians have cited fears that the event could have catastrophic consequences, referring to a passage in the Bible which reads: "The Sun shall be turned into darkness, and the moon into blood, before the great and the terrible day of the Lord comes."