Starry Night

Last Saturday night the local astronomical society organized its annual boat trip. The trip is an opportunity to see a truly dark sky, a sight which has become impossible to see on our overdeveloped and light polluted island.

The trip started at sunset in the fishing port of Marsaxlokk on board the trawler Padre Pio. The night was chosen because the moon was at a lunation of only 2.3 days and set early at 20:41. It showed a lovely crescent low over the horizon at sunset but Saturn and Mercury which lay close to it were invisible in the low haze.

The port of Marsaxlokk at sunset

As the boat travelled South East, the sky grew darker and the bright stars emerged, Arcturus, Vega, Antares were visible and Jupiter appeared to dominate the sky. Slowly the light pollution faded into the distance and the twilight ended revealing the night sky in all its glory.

The most amazing sight is our own galaxy, the Milky Way visible like a bright cloud arching across the sky from Sagittarius to Cassiopeia and reflected in the sea below. The countless stars blazed in the sky in a number so large that the normally easily recognisable constellations were drowned in the myriad stars making them hard to pick out. Meteors streaked in large numbers and early on a number of satellites were visible, most notably an Iridium flare which went approximately to magnitude +4.

The visibility of deep sky objects in such a dark sky is amazing. The Lagoon Nebula (M8) and Ptolemy's cluster (M7) were clearly visible to the naked eye. The Sagittarius star cloud (M24) stood out beautifully against the rest of the Milky Way.

I had my Celestron Skymaster15x70 with me and took my chance to use them to observe the dark sky. I went through a list of favourite deep sky objects. The most notable being the M4, M13, M27, M31 which filled much of the field of view, M6, M22 and M20. I also managed to see the North American Nebula (NGC 7000) for the first time. From my home location it isn't visible even with a 200mm Dobson. The "Gulf of Mexico" could be clearly seen.

I had prepared charts for the positions of Uranus and Neptune and I easily found them. Neptune was at mag +7.8 one third of the way between μ Cap and 42 Cap. Uranus lay below the circlet in Pisces on the extension of a line from ι Psc to λ Psc next to 20 Psc. At mag +5.7 Uranus was actually visible to the naked eye if one knew where to look.

The trip took us to a point 33.5 nautical miles to the South East of the island and drifted for two hours before heading back. At one point you could see the reflections of Jupiter and Venus in the sea on either side of the boat as dolphins darted between the waves and luminescent jellyfish glowed in the wake.

As the night wore on, more constellations rose in the East. Taurus appeared with the Pleiades, the Hyades and Mars. Auriga with its three magnificent open clusters M36, M37 and M38. Just before dawn Orion was visible with the belt stars hanging vertically over the horizon. Venus rose and then the sky lightened as the Sun put an end to the show.

Sunrise over the Mediterranean

This annual event shouldn't be missed by any local astronomy enthusiast for the unforgettable view it allows onto the universe.