This map shows the sky facing south tomorrow morning (March 15) with Mars very close to the star Beta Scorpii. Map: Bob King, source: Stellarium

Mars Gets Tight With A Bright Double Star / ExoMars / Possible Auroras March 14,15

This map shows the sky facing south tomorrow morning (March 15) with Mars very close to the star Beta Scorpii. Map: Bob King, source: Stellarium
This map shows the sky facing south tomorrow morning (March 15) at 5:30 a.m. local time (start of dawn) with Mars very close to the star Beta Scorpii. Map: Bob King, source: Stellarium

Mars is always on the move, so it’s inevitable it would run into something beautiful. Tomorrow and Wednesday mornings it slides very close to the gorgeous double star, Beta Scorpii, also known as Graffias, in the constellation Scorpius. Although the planet rises around 1:30 in the morning, you’ll see it best straight up south around 5:30 a.m. local time or right at the start of dawn. I know that timing stings, but if you happen to rise in the middle of the night and have a south-facing window, pull the curtain aside for a look.

Tomorrow (March 15), only 15 arc minutes — equal to half the a full moon diameter — separate star and planet. But on the next morning (March 16), they’ll really be close, just 9 arc minutes apart or 1/3 the moon’s diameter. You can’t miss ’em. Face south at the start of dawn and look for two bright red-hued “stars” about three fists up from the horizon. The lower one is Scorpius’ brightest star, Antares; above it, the Red Planet a full magnitude brighter.

This close-up view shows Mars' track alongside Beta Scorpii in the next few mornings. Map: Bob King, source: Stellarium
This close-up view shows Mars’ track alongside Beta Scorpii during the next few mornings. Diagram: Bob King, source: Stellarium

As fine as the view will be with the naked eye, a small telescope will reveal another dimension to this conjunction of two far-apart worlds: Graffias is a beautiful double star for low-power instruments. The main or brighter star, Beta-1, shines a little fainter than second magnitude, with a 6th magnitude companion orbiting close by to the northeast. They glimmer in a most beautiful way in the eyepiece. Add in Mars in the same field of view, and you’ve got a triple play!

Mars is still tiny but brightens a little more every day. This view was taken on March 13, 2016 and shows a large dark area in the northern hemisphere (top) called Mare Acidalium. The north polar cap is also visible. Credit: Anthony Wesley
Mars is still tiny but brightens a little more every day. This view was taken on March 13, 2016 and shows a large dark area in the northern hemisphere (top) called Mare Acidalium. A bit of the north polar cap is also visible. Credit: Anthony Wesley

If you use a magnification of 75x or higher, you’ll be able to see the planet’s gibbous phase and perhaps a couple dark surface markings. The north polar cap is currently visible (with difficulty) along Mars’ northern limb.

Today marks a special day for Mars in another way with the launch of the dual purpose ExoMars spacecraft. A joint venture between the European Space Agency and Russia’s Roscosmos, the probe is expected to reach Mars in seven months. On October 16, when the spacecraft is still 559,000 miles (900,000 kilometers) from the Red Planet, the lander will separate from the orbiter and three days later parachute down to the Martian surface. The orbiter will study rare gases in Mars’ atmosphere, in particular methane, which on Earth indicates either an active geology or biological processes.

The Schiaparelli lander, named for a 19th century Mars mapper, will descend to the surface on October 19th and study the environment including any electrical fields on the surface. Credit: ESA/ATG medialab
The Schiaparelli lander, named for a 19th century Mars mapper, will descend to the surface on October 19th and study the environment including any electrical fields present that might help to stir up dust. Credit: ESA/ATG medialab

While you’re out gazing at Mars, you may also get to see the northern lights. G1 or minor storming is forecast toward dawn tomorrow (March 15) and again tomorrow night from around 10 p.m. through 1 a.m. caused by a transition between slow and fast winds blowing from the sun. The moon’s about half and will brighten the sky some but probably not enough to ruin an aurora. Cross your fingers it’s clear!