A religious group in New Zealand is preparing for an apocalyptic event they believe will coincide with this month's blood moon.

A handful of Messianic believers are waiting to see if the fourth blood moon since April last year will be significant as predicted.

Based on the teachings of American Messianic Rabbi Jonathan Kahn, as well as a number of other unrelated religious individuals, Timaru group member Patricia Hughes believes "something probably will happen".

The blood moon on September 28 this year will fall on the first day of the Judaic Feast of Tabernacles, which Patricia thinks is poignant.

A blood moon is a total lunar eclipse (the moon crosses the earth's shadow) and is so named colloquially as it can appear to have a reddish-coppery hue.

In the book of Genesis in the Old Testament, which is considered important by Christians, Jews and Muslims, it talks of God creating signs in the heavens as an indication of judgment on earth.

"I think in September lots of things will happen ... maybe financial collapse," says Patricia.

She also points out that this month is the 14th anniversary of the September 11 attacks, when the Twin Towers in New York were bombed by terrorists. The anniversary was double the perfect number according to Judaism, which is seven.

"I'm trying to stock up a bit of food just in case."

Fellow Messianic group member Pat Goodwin says she was watching what may unfold with interest. Though not convinced anything will happen on a set date, she pointed out that every seven years since 1948 and the creation of the State of Israel, major world events had occurred, which was in line with the Hebrew cyclic tradition of forgiving debt.

Pat thinks believers should perhaps take the predictions as a warning of impending or future judgment.

Semi-retired astronomer and former superintendent at the University of Canterbury Mt John Observatory in Tekapo, Alan Gilmore, is not surprised that the blood moon will occur on a Jewish religious observance as they used a solar/lunar calendar. Each month started at a new moon.

"From time to time we get a run of total solar eclipses."

When they will occur can be dated with "high precision" and are noted up to 3000AD.

"When you get down to finer details, the rotation of the earth is a bit variable so precisely where it (eclipse) will be seen from is a small uncertainty."

The September 28 eclipse will not be seen from New Zealand during the day but will be able to be viewed from Europe, Africa and the Middle East, says Alan.

From Patricia's Messianic perspective, the dates and the times of the blood moons are all part of God's Plan.

Timaru New Life Church Pastor Gordon Rosewall is a little sceptical about such "end of world" predictions as they depend on calendar dates, theology and history.

"I believe Jesus will return to earth one day, just as he promised following his bodily resurrection. Whether in my lifetime or not is inconsequential. Therefore, if this is true, the most important thing is to be ready for his return."