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One of the lectures I will be giving on my cruise from Buenos Aires to Santiago is how the sky as seen from the southern parts of South America will look considerably different to the skies that Europeans and people from North America are used to seeing. Let me explain some of the obvious differences. First of all, although the Sun rises in the East and sets in the West in both the northern and southern hemisphere, if you are as far south as the southern parts of South America you need to look north to see the Sun. This means that you are facing north, and the Sun will appear to move from right to left across the sky, not from left to right as we northerners are used to seeing it. This can be quite disorientating.

Jupiter, and all the other planets, are visible from the Southern Hemisphere but again, one needs to look north to see them, not south. Just as in the Northern Hemisphere, Jupiter will dominate the evening sky for the next several months, and is in the constellation Cancer, slowly moving eastwards into Leo over the next 6-12 months.

The evening sky from Buenos Aires on the xx of March 2014. Jupiter is clearly visible, and will dominate the evening sky for the next several months. Notice up (further south) from Jupiter is the bright star Canopus, which again cannot be seen from Europe or North America

The evening sky (7:15pm) from Buenos Aires on the 5th of March 2014. Jupiter is clearly visible, and will dominate the evening sky for the next several months. Just as with the Sun, from this location you need to look north to see Jupiter, not south as in the Northern Hemisphere.


This next diagram below shows Orion and Sirius, two very well known things in the winter sky, but as you can see from the Southern Hemisphere everything looks upside down! We are used to seeing Orion with Betelgeuse in the top left and Rigel in the bottom right, but from Buenos Aires this is flipped; Betelgeuse is in the bottom right, and Rigel in the top left (just imagine looking at Orion from the Northern Hemisphere but standing on your head to do so!). Just as confusingly, we are used to seeing Sirius (the brightest star in the sky) below Orion, closer to the horizon, because it is to the south of Orion. But, from Buenos Aires, it is above it, further away from the horizon. Very confusing!

This shows how confusing the southern skies can be to someone from the Northern Hemisphere. Orion is upside down, and Sirius is above (further south) Orion, not below as we see it in the Northern Hemisphere.

This shows how confusing the southern skies can be to someone from the Northern Hemisphere. Orion is upside down, and Sirius is above (further south) Orion, not below as we see it in the Northern Hemisphere.


During the cruise, the other very bright object that people cannot miss is Venus, which is dominating the early evening sky. Venus will be at greatest eastern elongation on the 6th of June, which means that between now and then it will be moving further and further to the east of the Sun as seen from Earth (remember both we and Venus are moving in orbit about the Sun as this is going on), and as it moves further and further east the time between sunset and Venus setting gets bigger and bigger. On the 5th of March the Sun sets at 7:25pm from Buenos Aires, and Venus will set at 8:46pm. This gives a good hour to see Venus after sunset.
By early June, from the same location, the Sun sets at 5:50pm and Venus will set at 9:04pm, giving about three hours.



Venus is the evening sky as seen from Buenos Aires on the 5th of March at 7:14pm. At the moment Venus and Mars are close, and Uranus is near them too.

Venus is the evening sky as seen from Buenos Aires on the 5th of March at 7:14pm. At the moment Venus and Mars are close, and Uranus is near them too.



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