Mars stages its most brilliant showing in 15 years during late July and early August. The planet is at opposition, so it aligns opposite the Sun in Earth's sky. It is closest to Earth at opposition, and is especially close during this year's encounter, so it shines especially bright. It will outshine everything else in the night sky except the Moon and Venus, the "evening star." This picture, snapped July 15 at Lone Rock in Skull Valley, Utah, shows Mars, Saturn, and Jupiter, along with the asteroid Vesta. It shows the configuration around midnight local time for the week of July 23. [NASA/Bill Dunford]
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Mars at Opposition
StarDate:
July 23, 2018Mars blazes across the night sky this week. The Red Planet rises around sunset, scoots low across the south during the night, and sets around sunrise. It’s brightest for the year, too. In fact, for the next couple of months it’ll be the third-brightest object in all the night sky -- only the Moon and the planet Venus will outshine it.
Mars is staging such an amazing show because it’s at opposition -- it will line up opposite the Sun in our sky on Thursday night. It passes closest to Earth around opposition, so it’s a big, bright target.
Not all Mars oppositions are created equal, though. The planet’s maximum brightness varies by quite a bit from one opposition to the next.
That’s mainly because Mars’s orbit is quite lopsided. Its distance from the Sun varies by more than 25 million miles. When opposition occurs during summer, we pass Mars when it’s closest to the Sun. At the same time, Earth is farthest from the Sun -- about one million miles farther than average. That’s not a lot, but it helps. So at its closest, in about a week, Mars will be less than 36 million miles away -- just about as close as it’s possible for the planet to be.
Normally, Jupiter is the third-brightest object in the night sky. But right now, Mars outshines it by quite a bit. Look for it low in the southeast as night falls, and due south a few hours later -- a bright orange planet that dazzles all night long.
We’ll have more about Mars tomorrow.
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