A bright red star
A question I have been asked often in recent days is what is that bright, red star in the east. If you go out in the evening, this star can't be ignored. It is the brightest star in the east, and with its bright red colour, it is hard to miss. It is actually not a star at all, but our neighbour planet, Mars.
So why is Mars so bright and easy to see this month? In astronomical circles, we say that Mars is in ‘opposition'. This means that the Earth is directly between the Sun and Mars. The term refers to the fact that the Sun and Mars appear on opposite sides of the sky. It appears that as the Sun sets in the west, Mars rises in the east. In the morning when Mars sets, the Sun starts to rise.
Mars opposition happens every two years and two months, due to the orbits of the Earth and Mars. This is one of those years. Mars will be in exact opposition on 13 October, although the effect can be seen for weeks either side.
Another benefit of opposition is that Mars will be almost at its closest point to the Earth. This puts it in the perfect position to see some awesome surface details through even a decent telescope. This includes the polar ice caps. Even with a small telescope, Mars will appear as a large, bright disk. If you miss this opportunity of observing Mars in opposition, you will have to wait until December 8, 2022.
This closeness to Earth is also the reason that missions to Mars depart from Earth every two years. Just this year, a number of spacecraft launched on track to Mars. This includes NASA's Mars 2020 Perseverance rover, which will look for signs of past microbial life, collect and store rock and soil samples, and prepare for future human exploration. It also features the first helicopter drone, named Ingenuity, to fly on another planet. China's Tianwen-1 mission launched around the same time, as well as the United Arab Emirates Hope orbiter.