One of the true pleasures when sailing on open sea is watching the night sky. Far away from light pollution, one gets a good idea of how the mechanics work above and why this delicate dance of planets fascinated our ancestors. All planets, the moon and the sun move slowly from east to west – as earth rotates below. And sometimes they reverse course. It is sheer beauty how Venus opens this choreography every evening and closes it again in the morning.
The Perseid Meteor Shower is probably the most reliable Shooting Star Event
Since my time as boy scout I knew about the special treat one gets from the night sky in July and August. Our long hikes in the Swiss mountains often started at 3 am when it was still pitch dark - ideal time for star gazing. During these hikes we always spotted more shooting stars then during spring or fall. We tried to count them but there were so many that we lost count after a while. Can’t remember the number we reached. But remember that we always disagreed on the total count. It was fun though.
The Perseids as observed from the International Space Station
This fall, after 12 August, we will see many shooting stars as well. They are specks of dust which hit the atmosphere at high speed and burn up. But why is their occurrence not randomly distributed? Curiosity made me look up a couple of astronomy sites. The shooting stars we are going to see are called the Perseids. It is an impressive light show with up to 150 - 200 colorful shooting stars per hour.
The Perseids got their name from the constellation Perseus, a few fingers to the left of well know Cassiopeia (in the form of the “W”), from where they seem to radiate. But they actually originate from a dust cloud left by comet Swift-Tuttle which orbits the sun every 133 years and was discovered in 1862.
The 133 Year Orbit of Comet Swift-Tuttle around the Sun
Its perihelion (closest approach to the sun) is between Earth and Venus, its aphelion (furthest distance from the sun) is just a tad beyond Pluto. Swift-Tuttle made its last appearance in 1992. Our grand-grandchildren will see it again in 2126. Our Earth crosses the comet’s dust cloud every year.
Photo of a "supermoon" which is 1/3 brighter than an ordinary Full Moon
This year, it will be challenging to watch them though. Their appearance coincides with a “supermoon”. On 12th of August, the full moon will be at its closest point to Earth and thus looks about 15% larger. More importantly, the moon light will be 30% brighter than usual. The best time to watch the Perseids is thus early dawn, two hours before sunrise, when the moon has just set.
The very rare Alignment of six Planets (Uranus is not visible without a Telescope)
In June, there is another rare event in the sky. Mercury, Venus, Mars, Jupiter and Saturn will be lined up. Given that we have good binoculars on board we should also see Uranus which hangs just above Venues. Of course the alignment will be broken in August as the planets have moved on. But we will still see the remainders of the alignment.
Alignment as predicted by StarWalk - the Astronomy App I installed on my iPhone
Let’s download the free star chart apps on our iPhones so we can follow the spectacle. It should be happy star gazing. And maybe we agree on the number of shooting stars we spot.
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