You may recall marveling at the Red Planet Mars when I wrote about it earlier this year.
It reached its closest to Earth in mid-January when it lay only 60 million miles from us and shone as a bright orange “star” in the night sky.
If you’ve been paying attention to this planet over the past few months, you will have noticed that it has become noticeably fainter.
And if you’ve been watching it with a small telescope, you have certainly noticed that the planet now appears 30% smaller.
These differences have occurred because Mars and Earth have separated considerably as they’ve orbited the sun.
Today Mars is nearly twice as far from Earth as it was in January, and about three times fainter.
The one similarity to its appearance back then is that it still appears in the direction of the stars of Gemini, the twins, and now forms a fairly tight triangle with “twin stars” Castor and Pollux high overhead after dark.
Keep an eye on Mars over the next few weeks and you’ll notice how it appears to drift eastward among these stars, the result of its orbital motion and that of the Earth.
To get an even better idea of how Mars moves among the stars, you can sketch its position, or even take a photograph of the area, from week to week.
Simply fix your gaze (or that of your camera) on the “twin stars” of Gemini, and you’ll be able to record the movement of Mars very clearly over time.
By mid-April, the Red Planet will have left the stars of Gemini and will enter the constellation of Cancer, and will appear nearly three times fainter and, with a telescope, some 27% smaller than it does this week.
Keep watch longer and you’ll see that by May, Mars will pass quite close to the Beehive star cluster at the center of the constellation Cancer.
You can spot this cluster as a faint smudge of light on any clear, dark springtime night if you’re far from city lights and have no moonlight.
But on the evening of May 4, Mars will appear just to the north of the Beehive, and this should be a great time to view both with a small, low-powered telescope. Even with bright moonlight that week, a telescope will reveal the stars of the cluster.
The show doesn’t just occur on that night, however. As Mars orbits the sun, we can see its movement against the more distant stars if we’re patient.
On the evenings of May 3, 4 and 5, it will appear to drift by the cluster. Even through binoculars, Mars’ tiny orange disk will produce a lovely sight against the dozens of shimmering stars that form the Beehive.
This of course is an optical illusion caused by the two appearing along the same line of sight.
In reality, the Beehive is 577 lightyears (about 3,394 trillion miles) away, while Mars will then be some 26 million times closer (“only” about 137 million miles from us).
Spend some time under the stars this spring and enjoy watching this remarkable journey of Mars!
