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The Sky This Week
U.S. Naval Observatory's Weekly Blog
Reflections on "Perseverance"
by Geoff Chester, USNO Public Affairs
24 February 2021
Perseverance rover just before landing in Jezero Crater on Mars, 2021 February 18
View from the "sky crane" module that lowered the rover to a soft landing,
Image courtesy of NASA/JPL-Caltech.
The Moon brightens the overnight hours this week, beaming down from the near the bright Twin Stars of Gemini, Castor and Pollux as the week opens. Full Moon occurs on the 27
at 3:17 am Eastern Standard Time. February’s Full Moon is popularly called the Snow Moon or Hunger Moon as winter still holds its grip on northern climes. Luna spends the week among the stars of the rising spring constellations, though, a reminder that longer days and milder weather isn’t too far off in the future. Look for the Moon near the bright star Regulus in the constellation of Leo, the Lion on the evenings of the 25
. She ends the week rising in the late evening near the bright star Spica.
Last night, while taking the dog out for his evening “constitutional”, I looked up, as I usually do, at the evening sky. My view from the suburbs is severely limited by street lights, and the bright Moon’s scattered light washed out all but the brightest of winter’s stars. My gaze was drawn to a solitary object in the western sky. Comparable in brightness and color to the star Aldebaran, it certainly didn’t rival the brightest stars of the Great Winter Circle, but my gaze lingered on it for several minutes before the dog wanted to go back into the house. The object of my attention was Mars, which has graced our evening skies for several months. The planet is now a far cry from the blazing coal that it resembled back in October when it was closest to Earth, outshining all of the planets except for Venus. Now it’s just a small pink dot that shows a tiny disc in the eyepiece of my telescope.
However, last night it was different, because we, as humans, had once again succeeded in touching its surface with mechanical extensions of our minds and hands. I’m sure many of you were riding vicariously along with “Perseverance” as it slammed into the thin air of Mars at a speed of over 20,000 kilometers per hour (12,000 mph) and then, just seven minutes later, settled gently onto the planet’s surface. I have experienced this before with eight previous soft landings on the red planet, but this one was different. For the first time we were able to see a
“bird’s eye” view from a spacecraft landing on another planet
, albeit a few days after the fact. Still, we were along for the beginnings of a journey of discovery the likes of which I couldn’t imagine even when astronauts walked on the Moon. Both the Moon and Mars look a little different to me now, because in a sense I and everyone else who grew up in the “Space Age” have “been there”.
Exploration is in our blood. We have visited just about every corner of the Earth, from the summit of Mt. Everest to the bottom of the Challenger Deep, and from pole to pole. But while those endeavors were only experienced by a relative few, our exploration of the space around our home planet is shared by all. There has never been a time in our history when we all have had the chance to see new things and far-off places at the same time and for the first time. That little pink dot in the sky which I and countless others have looked at for hours on end with our telescopes is now a “place” that is ready for our close-up exploration. It’s going to be an amazing ride.
From our Earthbound view Mars continues to shine in the evening sky. This week the planet moves toward the Pleiades star cluster, presenting a lovely binocular sight by the end of the week. He will continue his steady eastward course throughout the first half of the year.
Perseverance Mars 2020
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