Mars is at its closest, growing brighter
Posted October 6, 2020 10:00 a.m. EDT
Updated October 6, 2020 12:22 p.m. EDT
Mars has been bright and beautiful in the evening skies all month. Look to the east after sunset.
Earlier today, the speedier Earth caught up with and passed Mars on their race around the Sun. This planetary lapping is also known as closest approach, or perigee. Mars is the closest it will be to Earth until 2035.
Mars is 38.6 million miles away. That orangy light you see in the eastern sky after sunset takes about 3.5 minutes to make it to your eye.
That may seem like a long way, but by September 2021, Mars will be 245.2 Million miles away increasing that light time to nearly 22 minutes.
Exploring Mars is risk when it takes nearly 45 minutes to send commands and receive a response from robots. This is why scientists and engineers at NASA's Jet Propulsion Laboratory added even more autonomous features to the Perseverance rover currently en route to Mars. They can make their own decisions about how to safely go about the science NASA commands it to do.
"We could see the area before the dip, and we told the rover where to drive on that part. We could see the ground on the other side, where we designated a point for the rover to end the drive, but Curiosity figured out for herself how to drive the uncharted part in between," said John Wright, a rover driver with NASA's Jet Propulsion Laboratory of Perseverance's twin which has been studying Mars since 2012.
Perigee isn't the only date astronomers have marked on their Mars calendar.
Opposition occurs as Earth passes between Mars and the Sun. The Sun and Mars are opposite each other in the sky. This occurs next on October 13, 2020. This is also when the full disk of the planet will be illuminated, reflecting the most light back to Earth, making it the brightest we'll see until December 2022.
This close approach happens every 26 months. NASA, the European Space Agency and most recently ISRO, India's Space Agency, have these dates circled on their calendars because they offer the best times to reach Mars. 2035 has a big circle around it for a couple of reasons.
NASA's plans to send humans to Mars focus on 2035 for a couple of reasons. It is far enough in the future to enable enough of the challenges between us and boots on Mars to be solved. That opposition event also coincides with another celestial mechanics event, perihelion, the closest point in Mars' orbit to the Sun. That's an especially good time to send a rocket to Mars.