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The Sky Tonight - October, 2008

Jupiter is still visible throughout October, setting by 10pm local time. Look low towards the south-west and it is the brightest object in the sky. Take a look through binoculars, and see if you can spot the four bright Galilean moons that orbit around Jupiter. Our Moon is conveniently close to Jupiter in the night sky on the 6th & 7th of October, acting as a useful guide.

The Moon begins the month as a thin crescent - a beautiful sight in the evening sky. The Moon reaches full Moon, when it is on the opposite side of the sky to the Sun, on the 14th.

The summer triangle is still visible in October, despite its name, high in the South at 7pm. The three stars that make up the triangle are Vega, Altair & Deneb. Vega is the brightest of the three stars, and there maybe a planet like Jupiter in orbit around Vega. Altair is interesting because it rotates in just 7 hours! And Deneb is actually one of the brightest stars we know of - some 250,000 times bright than the Sun! The reason it looks fainter than Vega is only because it is much further away - Deneb is some 100 times further away than Vega. If Deneb was as close as Vega, it would be as bright as the Moon!

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This page contains a single entry from the blog posted on October 8, 2008 10:07 AM.

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