Until February 20 the five brightest planets in the sky - Mercury, Venus, Mars Jupiter and Saturn - will be aligned in the early morning sky with each planet being able to be seen with the naked eye.

This is the first time since 2005 that the planets have aligned, with the best viewing time for the alignment being between 4.30am and 5.30am.

Darby's Falls Observatory's Mark Monk was getting great photos of the planets with just his small compact digital camera held up to the telescope's eye piece.

"Just before dawn is when you can see them.

"Though without a telescope you won't see much of them, they'll just look like a bright star," he said.

"We have 10 telescopes and with how we are set up have 100 people come through, with a dome you would only get about 10 people through."

Mr Monk said he doesn't run the observatory for the money but for the opportunity to teach people about the universe.

"I've had elderly women come up to me with tears in their eyes saying that the tour we have here was one of the best things they've ever seen in their lives.

"When you think about it 98 per cent of the mass in our solar system is in the Sun, of the remaining two per cent almost all of that is in Jupiter and the Earth's mass is less then 100th of one per cent,"

"We really are just a placenta left over from the birth of the Sun," he said.

The observatory is open from 8.30pm to 11pm during the summer daylight savings period with other openings by appointment.