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My July fund-raising campaign, celebrating the 13th anniversary of the start of this website, has now ended. This was the second most successful monthly fund-raising campaign ever. Thank you again to everyone who has who donated or subscribed. It is difficult to explain what your support means to me.


You can still donate or subscribe to support my work if you wish, either by giving a one-time contribution or a regular subscription. There are four ways of doing so:


1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.


2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.

3. A Paypal Donation:

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5. Donate by check, payable to Robert Zimmerman and mailed to
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Ingenuity in close-up after two years on Mars

Ingenuity in close-up after two years on Mars
Click for original image, with more information about it here.

With the Mars rover Perseverance now only about seventy-five feet away from the helicopter Ingenuity, the closest the two robots have been on Mars since Ingenuity was deployed in April 2021, the science team used Perseverance’s high resolution camera to take a new close up of the helicopter.

That picture, reduced and sharpened to post here, is to the right. From the caption:

Small diodes (visible more clearly in this image of helicopter) appear as small protrusions on the top of the helicopter’s solar panel. The panel and the two 4-foot (1.2-meter) counter-rotating rotors have accumulated a fine coating of dust. The metalized insulating film covering the exterior of the helicopter’s fuselage appears to be intact. Ingenuity’s color, 13-megapixel, horizon-facing terrain camera can be seen at the center-bottom of the fuselage.

This close-up is important to determine the overall state of the helicopter after two years on Mars. The engineering team that operates it does not know how much longer Ingenuity can last, so any data on its condition is extremely helpful.

That fine coat of dust on the panel and the rotors tells us that even flight and fast-rotating motion is not enough to keep such things clean on Mars. Thus we learn that there is likely no quick solution to the accumulation of dust on solar panels on Mars.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • Col Beausabre

    How about a teenager with a wet cloth looking to make a buck?

  • Edward

    Robert noted: “That fine coat of dust on the panel and the rotors tells us that even flight and fast-rotating motion is not enough to keep such things clean on Mars. Thus we learn that there is likely no quick solution to the accumulation of dust on solar panels on Mars.

    Well, there go a bunch of dreams for solving that problem. But, maybe we can reduce the accumulation and extend the lifetime of some of our robots by a couple of years or so.

  • I wonder if the motion could cause static charges that cause fine dust to accumulate and stay as long as there is a charge? just wondering.

  • Gealon

    If we can’t find any teenagers with squeegees on Mars, we could settle for a rotating brush, as one of the tools on the arm and an epoxy or similar coating, over the cells so we don’t rip them up with said rotating brush. Or just wait a while until we are importing said teenagers to Mars with a Starship.

  • GaryMike


    Dust removal isn’t part of the design because a failed mission is soon followed by a similar mission design, ensuring continued employment for the makers of this iterative replacement.

    Think Ariane 6. Ariane 5 with a couple upgrades.

    European countries shuffle money amongst themselves based on their proportional contributions. And their expected proportional ‘distributions’.

    They’ll never recoup their costs because they’ll never again have significant market share for some kind to come..

    ArianeSpace may survive as asteroid miners.

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