These two bright stars in the sky will be seen together for the next few months. The reddish "star" is actually the planet Mars and it will continue to get brighter as Earth and Mars get closer together on their orbit around the Sun. Spica is the bluish star, however, it is constantly one of the brightest blue star in the sky. What is amazing is that this star has been seen throughout human history, all the way back to ancient times.
The reason why Mars appears to be reddish is because of its soil. It is found that Mar's soil is abundant in iron which gives it a reddish tint. It is not completely known why it has so much iron in it but some possible explanations are that once there was warm water flowing on Mars which carved out long channels through the planets. The rocks with iron would have slowly been worn away by the rivers and the sea, and the oxygen in the water would have combined with the iron and make iron oxide which would have made the iron rust and turn into red dust. The mineral would then be dispersed throughout the planet through rain. Another explanation would be that the iron came from meteorites that have hit Mars in the past. Whatever it is, Mars is still one very beautiful and mysterious planet.
Spica is seen as blue because it is a blue giant! It is actually a binary star, which means that it revolves around a common, central point with another stellar object, yet they are so close together, the two stars are not easy to see. Another reason why it is so bright is because it is one of the nearest massive binary star systems to the Sun; that and the fact that it is 10 times the mass of the Sun, 7 times the radius of the Sun and 12,100 times the luminosity of the Sun... no big deal.
Other information about this photo is that it was taken last week in Sweden. Who says you can't be creative for astronomy?
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