标签: mars

I don’t know if I've mentioned this before, but I'm tremendously interested in rockets and space probes and planets and solar systems and galaxies and the wonders of universe in general (I don’t like to limit myself). As you are no doubt aware, for the last couple of days the world has been buzzing with the news that, for the first time, scientists have confirmed small amounts of liquid water flowing on the surface of present-day Mars.   This raises the possibility that if life ever managed to claw its way up on Mars, then there may still be living organisms there now. If we were to detect life on another planet, this would dramatically change our perspective on... well, a lot of things, really.   The reason I'm waffling on about this here is that I was chatting with my chum Adam Taylor this morning. Adam never fails to surprise me when it comes to the cool imaging activities his company -- e2v in the UK -- is involved in. During today's conversation, for example, he casually mentioned that e2v played a part in the discovery of the Martian water.   It turns out that the Mars Reconnaissance Orbiter (MRO), which was launched in 2015 and which is currently orbiting Mars, contains something called the High Resolution Imaging Science Experiment (HiRISE). In turn, the HiRISE camera boasts e2v image sensors, which allow it to combine very high resolution and signal-to-noise ratio with a large swath width, thereby allowing it to collect images of unprecedented detail. It was HiRISE that captured the image below:   (Image courtesy of NASA / Jet Propulsion Laboratory / University of Arizona)   Scientists believe that the dark, narrow, downhill streaks in this image -- especially the fact that they are changing over time -- are evidence of water flowing on Mars.   Unfortunately, these satellite images are the closest we have at the moment, but I live in hopes that humans will visit and explore Mars in person in my lifetime. Meanwhile, with regard to the "Never-Before-Seen Close-Up Photo" promised in the title of this column, I offer you the following image:   (Image courtesy of Max Maxfield and Bruce Till)   How do I know this little scamp has never been seen before? Well, I feel confident in making this claim because my chum and graphics artist guru, Bruce Till, who sits in the office next to mine, just created it for me a few minutes ago. Hmmm, looking at this image is making me hungry; now I fancy a Mars Bar!

Assessing the thermal effects on general purpose pc boards is challenging, but it's another story to control board reliability in mission critical applications where a device failure is not an option. In a recent discussion, Andy Burkhardt, technical marketing specialist at Polar Instruments, acknowledged the reliability issues for pc boards, adding: "Certainly moisture ingression, humidity and temperature all have effects on PCBs. More generally on reliability as a catalyst contributing towards other failure mechanisms, but particularly on insertion loss of surface microstrip traces and slightly less so for strip-line transmission line structures." Superior reliability is the pivotal issue for mission critical applications. Devices have to continue to function correctly and reliably under harsh and, sometimes severe conditions, including high moisture and humidity, high heat, freezing cold, electromagnetic interference and destructive electromagnetic pulses. Think about the Mars Science Laboratory rover, Curiosity, which landed at Gale Crater on Aug. 6, 2012. It integrates the highest-end technology sensors and measuring systems to conduct unprecedented experiments on the Red Planet. Curiosity has a number of pc boards communicating, interfacing, regulating and controlling various sensors and other scientific gear Take, for instance, Curiosity's Mars Hand Lens Imager (MAHLI), which uses a 2-megapixel colour camera with a focusing macro lens to observe textural, mineralogical, structural and morphological details in geologic materials. The MAHLI camera head electronics are laid out as a single rigid-flex substrate with three rigid sections that are sandwiched between housings that provide mechanical support and radiation shielding.   Location of MAHLI hardware aboard the Mars Science Laboratory rover, Curiosity, in the Spacecraft Assembly Facility (Source: NASA) The aerospace industry requires pc boards with high reliability in extreme conditions. The MAHLI camera head is usually operated at temperatures of -40°C to +40°C on Mars. For that, NASA said it has been verified through testing on a non-flight unit to be able to survive nearly three Mars years of diurnal temperature cycles (down to -130°C) without any heating.   The graph shows the rise and fall of air and ground temperatures on Mars obtained by NASA's Mars Curiosity rover. The data cover Aug. 16 to Aug. 17, 2012, and were obtained by the Rover Environmental Monitoring Station. Ground temperatures vary from as high as 37 degrees F (3 degrees C) to as low as minus 131.8 degrees F (minus 91 degrees C), showing large temperature oscillations from day to night. ( Source: NASA ) The imperatives are different, though, when human lives are at stake. If Golden Spike, a private company whose board includes former NASA engineers and spaceflight experts, delivers on its promises, it will offer rides to the moon by 2020 –for the modest sum of $1.5 billion for two people. Advancing to new frontiers is exhilarating but, as lives depend on the products we provide, it's fundamental to never compromise on safety. Therefore, the aerospace electronics industry must continue to design products that meet the absolute highest standards.   Anne-Francoise Pele EE Times  

Identifying the thermal effects on general purpose pc boards is tough, but it's another story to control board reliability in mission critical applications where a device failure is not an option. In a recent discussion, Andy Burkhardt, technical marketing specialist at Polar Instruments, acknowledged the reliability issues for pc boards, adding: "Certainly moisture ingression, humidity and temperature all have effects on PCBs. More generally on reliability as a catalyst contributing towards other failure mechanisms, but particularly on insertion loss of surface microstrip traces and slightly less so for strip-line transmission line structures." Superior reliability is the pivotal issue for mission critical applications. Devices have to continue to function correctly and reliably under harsh and, sometimes severe conditions, including high moisture and humidity, high heat, freezing cold, electromagnetic interference and destructive electromagnetic pulses. Think about the Mars Science Laboratory rover, Curiosity, which landed at Gale Crater on Aug. 6, 2012. It integrates the highest-end technology sensors and measuring systems to conduct unprecedented experiments on the Red Planet. Curiosity has a number of pc boards communicating, interfacing, regulating and controlling various sensors and other scientific gear Take, for instance, Curiosity's Mars Hand Lens Imager (MAHLI), which uses a 2-megapixel colour camera with a focusing macro lens to observe textural, mineralogical, structural and morphological details in geologic materials. The MAHLI camera head electronics are laid out as a single rigid-flex substrate with three rigid sections that are sandwiched between housings that provide mechanical support and radiation shielding.   Location of MAHLI hardware aboard the Mars Science Laboratory rover, Curiosity, in the Spacecraft Assembly Facility (Source: NASA) The aerospace industry requires pc boards with high reliability in extreme conditions. The MAHLI camera head is usually operated at temperatures of -40°C to +40°C on Mars. For that, NASA said it has been verified through testing on a non-flight unit to be able to survive nearly three Mars years of diurnal temperature cycles (down to -130°C) without any heating.   The graph shows the rise and fall of air and ground temperatures on Mars obtained by NASA's Mars Curiosity rover. The data cover Aug. 16 to Aug. 17, 2012, and were obtained by the Rover Environmental Monitoring Station. Ground temperatures vary from as high as 37 degrees F (3 degrees C) to as low as minus 131.8 degrees F (minus 91 degrees C), showing large temperature oscillations from day to night. ( Source: NASA ) The imperatives are different, though, when human lives are at stake. If Golden Spike, a private company whose board includes former NASA engineers and spaceflight experts, delivers on its promises, it will offer rides to the moon by 2020 –for the modest sum of $1.5 billion for two people. Advancing to new frontiers is exhilarating but, as lives depend on the products we provide, it's fundamental to never compromise on safety. Therefore, the aerospace electronics industry must continue to design products that meet the absolute highest standards.   Anne-Francoise Pele EE Times  

Good grief, my brain is now reeling with all of the interesting info that is flashing before my eyes... First I got sucked into a series of articles on the Reuters.com website. For example, it seems that astronomers have detected an exotic planet that appears to be formed largely out of diamond. I have no idea how they work out this sort of thing ( Click here to see this article). As an aside, this made me think about the World of Tiers books by Philip José Farmer. These tales are set within a series of artificially-constructed universes, created and ruled by decadent beings who are genetically identical to humans, but who regard themselves as superior, the inheritors of an advanced technology they no longer really understand. I read the first book in the series – The Maker of Universes – when I was a young lad and it totally captivated me. It starts with an older guy called Robert Wolff (I think he's about 65 and feeling his aches and pains ... one of which is his wife). Wolff is transported to a strange new world, the World of Tiers, where he starts to grow young again and has a bunch of adventures before he discovers... Ha! You don't think I'm going to give the game away that easily, do you? In fact I recently found that the world of tiers books had been gathered into two volumes: Volume 1 The Maker of Universes (1965) The Gates of Creation (1966) Volume 2 A Private Cosmos (1968) Behind the Walls of Terra (1970) The Lavalite World (1977) Sadly, the books and these compilation volumes are all long out of print. Happily, I recently managed to acquire copies of both volumes from a secondhand book store. I read Volume 1 a couple of weeks ago and Volume 2 is sitting on my desk waiting for me to have a spare moment... maybe on the coming holiday weekends... But we digress... after reading about the diamond planet, I took a slight detour when my old chum Jay Dowling sent me a link to an article about a black hole eating a star on the HuffingtopPost.com website ( Click here to see this article). Then it was back to Reuters.com to read an article about the recent discovery of the Earth's oldest fossils in Australia, which provides evidence that early sulphur-based cells and bacteria were able to thrive in an oxygen-free world more than 3.4 billion years ago. In turn, this supports the idea that similar life forms could exist on other planets where oxygen levels are low or non-existent ... like Mars, for example ( Click here to see this article). From here I wandered into an article about the fact that recently analysed images from NASA's Mars Reconnaissance Orbiter satellite provide evidence of liquid water occurring today on Mars. Arrgggh, I can't help myself. All this talk about Mars reminded me about that hole the size of a football field that was discovered on Mars. This hole – which appears pitch black – is so deep that its insides are completely un-illuminated by the Sun and consequently so dark that nothing can be seen inside. The theory is that this is the entrance to a huge underground cave that may be capable of protecting Martian life, should such life exist ( Click here to visit the appropriate page on the NASA website). And then it was back to Reuters.com again. Have you ever wondered why the face of the moon pointing towards Earth has so many craters and tends to be rough and bumpy (as it were), while the far side of the moon is relatively smooth? I've heard quite a few theories about this ... and now there's a new one. The prevailing hypothesis today is that the Earth–Moon system formed as a result of a giant impact: a Mars-sized body hit the nearly formed proto-Earth, blasting material into orbit around the proto-Earth, which accreted to form the Moon. Well, new research suggests that the blasted material originally formed two moons. After about 100 million years, the smaller moon finally crashed into the larger moon leaving one side rough and the other side smooth ( Click here to see this article). As as I pen these words, I wonder what nuggets of knowledge and tidbits of trivia will the afternoon the next few days bring...