The Moon and Mars will be visible together this weekend … though please ignore the scale in this … [+] ‘creative’ mock-up!
You’ve seen three spacecraft launches to Mars this summer and you’ve read about the possibility of ancient life there.
Now see the “red planet” with your own naked eyes, with a bright Moon in tow, just for good measure.
This coming weekend the Moon will align with Mars, though exactly when it will look closest depends on where you are on the planet.
Mars is now rising just after dark in the east, while the Moon is going to be 86%-lit, which is known as a “waning gibbous Moon”.
The Solar System is like a fried egg; planets orbit the Sun on the same plane, so in our night sky there’s a line—known as the ecliptic—that all the planets orbit. It’s also the path that the Sun takes through our daytime sky. The ecliptic stretches from east to west in our sky, and at this time of year, it’s southerly from the northern hemisphere; you’re likely to see planets in the east, southeast, south, southwest and west. Never look for planets in the north!
Since all the planets orbit in the same direction, but at different speeds, they catch-up and overtake each other, changing their apparent position in our night sky.
The Moon’s orbital path around Earth is only slightly inclined to the ecliptic, so every so often it passes very close to planets. In fact, the Moon and Mars aligned last month, too.
However, Mars appeared to be both smaller and dimmer back then. The real reason to watch the Moon and Mars this weekend is because the red planet is now becoming impressively big and bright.
The waning gibbous Moon will make its apparent closest approach to the “red planet” on the night of Saturday, September 5, 2020 for North America (eastern sky) and in the early ore-dawn morning on Sunday, September 6, 2020 morning for Europe (western sky).
Here’s a handy sky-chart for North America (if you’re in Europe, it will also work, though the absolute closest approach is about five hours later just before sunrise, by which time Mars and the Moon will be in the west).
The two objects will be about half a degree apart, though if you look on Friday or Sunday evenings you’ll also notice them pretty close—about 4°, in fact.
Absolutely not! Don’t fall for that hoax. Although Mars will look relatively big and bright, the Moon will look so much larger. After all, it’s way closer to us than Mars.
While the Moon will be about 238,000 miles from Earth this weekend, Mars will be about 47 million miles distant. For it to appear to be as big as the Moon, Mars would need to be about 476,000 miles from Earth—that’s just over about twice the Earth-Moon distance.
Mars is now getting towards its opposition in October, the point in its orbit when it’s closest to Earth. That means it’s now getting bigger and brighter in our night sky. In fact, it’s getting visibly bigger and brighter each week.
Knowing about Mars’ opposition also reveals why NASA, China and the UAE just launched their missions to Mars. Earth takes 365 days to orbit the Sun and Mars takes a slower 687 days. That’s 1.88 Earth years, which puts Mars and Earth reasonably close to an orbital resonance of 2:1.
Earth takes 365 days to orbit the Sun and Mars takes a slower 687 days.
So just over every two years Earth catches-up on Mars and the planets briefly line-up. At that point they’re closest together. So just before that point the journey between the two planets takes the least amount of time. Every 2.2 years a launch window opens for efficient, cost-effective rides between Earth and Mars, and vice versa.
While you wait for the three spacecraft to reach Mars, take a look at the red planet with your own eyes this weekend. With the Moon close by, it will be impossible to miss—and a sight to remember.
Note: Star charts here are for 40º North latitude. If you need exact information for where you are please consult an online planetarium like The Sky Live.
I’m an experienced science, technology and travel journalist interested in space exploration, moon-gazing, exploring the night sky, solar and lunar eclipses,
I’m an experienced science, technology and travel journalist interested in space exploration, moon-gazing, exploring the night sky, solar and lunar eclipses, astro-travel, wildlife conservation and nature. I’m the editor of WhenIsTheNextEclipse.com and the author of “A Stargazing Program for Beginners: A Pocket Field Guide” (Springer, 2015), as well as many eclipse-chasing guides.
World news – US – How, When And Where To See The Moon And Mars Shine Together This Weekend With Your Naked Eyes