It's not predicted to be the best lunar eclipse of all time, but Tuesday night’s red moon is still expected to attract stargazers to the Illawarra’s best vantage points.
Wollongong-based astronomer Glen Moore said the beach and the escarpment would be the best places to watch the eclipse.
‘‘It’s not a phenomenon that is really significant to astronomers, it’s more general interest,’’ he said.
‘‘Plus everyone can get out there and have a look.’’
Peak viewing times will be from when the moon rises just before 5.30pm, with the maximum eclipse happening at 5.46pm.
The total eclipse is due to end at 6.25pm, while the earth’s shadow will completely have moved away from the moon by 7.33pm.
But forecast heavy cloud and wet weather could hamper viewing opportunities in the Illawarra.
The timing of the eclipse also means the moon will be rising already in the earth’s shadow.
Mr Moore said the ‘‘red moon’’ effect was similar to what happened during a bushfire.
‘‘When sunlight passes through atmosphere blue light is scattered and red light is transmitted that’s why we see blue sky in day time,’’ he said.
‘‘The light going through the earth’s atmosphere and reaching the moon is only red light because the blue light has been scattered away on its way to the moon.
‘‘If you look at the sun during a bushfire for instance there are lots of particles in the air and that’s why the sun sometimes looks deep red when looking through smoke.’’
Mr Moore said ancient people had used lunar eclipses to calculate the size of the earth relative to the moon.
‘‘What is really interesting is the curvature of the shadow on the moon is greater than curvature of moon itself so the ancients were able to work out the earth is four times bigger than the moon,’’ he said.