In the image below, you’ll see two wide solar system views: one focused on the inner solar system through the main asteroid belt and one zoomed out to encompass the Kuiper belt. I have added colored arrows to the orbits of the planets to demonstrate where in each orbit the seasons shift.
Insets show you the exploration action at Mars, at our Moon, and at L1, a gravitationally stable point between Earth and the Sun. I don’t show spacecraft in Earth orbit. You’ll see all the robots that are currently in routine communication with Earth, plus 3 others. The Kepler and Dawn missions ended on 30 and 31 October. Opportunity’s status remains uncertain.
I have to apologize for leaving out two interplanetary spacecraft from the inaugural version of this column. I’ve now added in NASA’s Parker Solar Probe, on its way to pass through the solar atmosphere, and China’s Longjiang-2, the first CubeSat to enter lunar orbit. We had to print this magazine before China’s Chang’e-4 lander was scheduled to launch on 8 December; optimistically, I’ve placed it on the lunar farside. By now, you’ll know if my guess was correct.
The final quarter of 2018 has had a lot of comings and goings. The first quarter of 2019 looks to be less momentous, with only India’s Chandrayaan-2 slated for launch toward the Moon.