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Christmas present from NASA Ken Perrott Dec 16

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Photography can produce some great abstract art. Even if it’s of the very large or very small.

Here’s some really beautiful abstract art based on photograph of earth taken from orbit.

Great-Salt-Desert

The Dasht-e Kavir, or Great Salt Desert, is the larger of Iran’s two major deserts, which occupy most of the country’s central plateau.

From the introduction:

In 1960, the United States put its first Earth-observing environmental satellite into orbit around the planet. Over the decades, these satellites have provided invaluable information, and the vantage point of space has provided new perspectives on Earth. This book celebrates Earth’s aesthetic beauty in the patterns, shapes, colors, and textures of the land, oceans, ice, and atmosphere. The book features 75 stunning images of Earth from the Terra, Landsat 5, Landsat 7, EO-1, and Aqua satellites. Sensors on these satellites can measure light outside of the visible range, so the images show more than what is visible to the naked eye. The images are intended for viewing enjoyment rather than scientific interpretation. The beauty of Earth is clear, and the artistry ranges from the surreal to the sublime.

Earth as art—enjoy the gallery.

NASA Science Mission Directorate

Earth Science Division

Download your gift:

As a PDF

As the Accompanying iPad App

via NASA – “Earth As Art”.

Thanks to ebook friendly

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A sundial on Curiosity? Ken Perrott Aug 15

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When I saw the first reports of this on Twitter I thought it was a joke. A sundial on Curiosity? Just in case the computer packs up they can still tell the time? I thought some wag was pulling our collective legs with a photo of one of the rover’s antennae.

But, turns out this is something like a sundial. Its a Marsdial – actually a calibration target enabling photographs to be corrected for colour. BIll Nye, from the Planetary Society, describes its role in Curiosity’s Marsdial is on Mars!

“As I’m sure you’re aware, geologists love rocks, and they especially love the rocks on Mars. The first thing they all want to know about a rock is what’s it made of. For that, it’s good to just take a look at the color of the rock surface. When everything is being done on the alien landscape of another world, it’s easy enough to electronically get the color wrong, or not quite right. To that end, artists, photographers, and a few scientists have noticed that by looking at the color of a shadow on a neutral white or gray background, you can infer the color contributed to the scene by the sky.

On Earth, shadows take on a sky blue tinge (what I like to call “cerulescence”). On Mars, it’s a salmon color (what I like to call “arangidescence”). And so, the MarsDials bear a small metal post that casts a shadow onto some white and gray rings of known value or grayness.”

The NASA animation above is made up from four Mastcam images of the calibration target — the Marsdial. They were taken on Curiosity’s sol 3 (August 9, 2012) over a period of about 8 minutes. In that time, the shadow moved slightly, marking time on Mars with a sundial. (You may need to click on the photo to see the animation).

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Scientific shift work Ken Perrott Aug 14

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Some of the people on teams managing the rovers on Mars call themselves “Rover drivers” or “Mars drivers.” Of course, things are not that simple. It is not possible to drive a vehicle on Mars in real-time from Earth. Instead, computer code must be uploaded to enable the vehicle to carry out planned manoeuvres, analyses, etc., autonomously.  And the computer code can only be written after the results of the previous commands are known.

In practice, this involves large teams of engineers, software experts and scientists. Each team has their own work – and the teams need to interact to plan the rover’s work, iron out priorities, and deal with problems. This work has to occur at strange times, and with deadlines, to fit in with the activity and day/night programme on Mars. Energy limitations means that the rover usually does not operate during the Martial day.

So all this work, the meetings of each team and their joint meetings, and decisions about planned activity must take place before the rover “wakes up.” And because the results from the previous day’s activities feed into this detailed decision cannot be made and code written until after that data has been downloaded and analysed.

The graphic above was shown in one of the recent Mars Science Laboratory – Curiosity – media briefings. It indicates the time line for the Laboratory to be active (“awake”), the downloading of data via the Mars Odyssey and Mars Reconnaissance orbiters, assessment of data, planning of future activity (particularly that for the next day), interaction of engineering, scientific and software teams, integration of plans, validation and approval and then the sending of the new commands to Curiosity as it “wakes up” for the new day.

I note they have even left a brief time gap “margin” to handle unforeseen problems.

It must be fascinating to work in large teams like this on scientific projects. And I am sure there are also political and emotional problems that need management as well as the engineering, scientific and software problems. Apparently with groups managing Mars rovers the shift-work, and the drift in shift times because of mismatch in the length of the Earth day and the Mars sol, causes “jet lag.” So the emotional and human issues resulting from this also need management.

Andrew Kessler gives an idea of the procedures involved in managing Mars rovers and landers in his book Martian Summer: Robot Arms, Cowboy Spacemen, and My 90 Days with the Phoenix Mars Mission. This is based on his own experiences as a journalist embedded in the teams managing the recent Phoenix lander. It’s a bit of an eye-opener – at least for someone who hasn’t worked in such large scientific teams before.

See Working on Mars for my review of that book.

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Infectious jubilation Ken Perrott Aug 07

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Crowd in New York’s Times Square celebrate successful Mars landing – 1:30 am. Credit: Jason Major (@JPMajor)

The mass interest in the current Olympics, and yesterday’s landing of the Curiosity Rover on Mars really brought home to me that we are an empathetic species. We celebrate the achievements of others and feel the jubilation they do when things go right.

And with Curiosity’s successful landing I think we also celebrate the achievement because we see that it belongs to all of us. It is an achievement for all humanity.

The achievement is huge. The technically difficult landing seemed to go without a hitch. Scientists and engineers at NASA’s Jet Propulsion Laboratory were receiving images within minutes. Everyone was aware that attempts at Mars landing have a history of failure.

The descent by parachute was photographed by a high-resolution camera on board the Mars Reconnaissance Orbiter. – see below.

Photo: NASA – Curiosity Spotted on Parachute by Orbiter.

That seems incredibly lucky but clearly a lot of skill and technology went into this achievement as well. As Phil Plait wrote on Bad Astronomy:

“The simple and sheer amazingness of this picture cannot be overstated. Here we have a picture taken by a camera on board a space probe that’s been orbiting Mars for six years, reset and re-aimed by programmers hundreds of millions of kilometers away using math and science pioneered centuries ago, so that it could catch the fleeting view of another machine we humans flung across space, traveling hundreds of million of kilometers to another world at mind-bending speeds, only to gently – and perfectly – touch down on the surface mere minutes later.”

According to a media briefing earlier today the full version of this image also shows the abandoned heat shield which landed some distance from the Curiosity’s landing site.

Patience

Now we have to be patient while Curiosity is checked out by engineers and slowly brought into full functioning. It will be weeks before the vehicle starts driving around, sampling soil and rocks, and analysing samples.

Even the downloading of images already captured will take time. So far we are only seeing relatively low resolution images. Large teams of engineers and scientists will be working strange hours (the slightly different length of the Martian day (sol) and the Earth day causes “jet lag” for these people) receiving data, planning experiments, writing code and uplifting code and instructions.

Andrew Kessler gives an idea of the activity and life style of the teams involved in managing the last Mars lander – Phoenix – in his book Martian Summer: Robot Arms, Cowboy Spacemen, and My 90 Days with the Phoenix Mars Mission. For my review of this book see Working on Mars.

See also:
Curiosity requires patience
Going for gold – on Mars
Seven Minutes of Terror
Christmas gift ideas: Working on Mars

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Curiosity requires patience Ken Perrott Aug 06

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The Mars Science Laboratory, Curiosity, lands today – hopefully (5:31 pm NZ time). But when will we know if the landing has been successful?

Communication between Mars and Earth is hardly simple. It’s not just the time delays involved (currently about 15 min). There’s also rotation of both planets. So communication with Curiosity (if it lands successfully) will involve three satellites in orbit around Mars – the Odyssey Orbiter, the Reconnaissance Orbiter and ESA’s Mars Express. (Watch this video to see the alignment of Curiosity, Odyssey and Reconnaiscance during landing). Messages, and particularly data, may need to be stored on board Curiosity or the satellites before transmission to earth.

So we may not even have confirmation of Curiosity’s safe landing for several hours – maybe even several days. This video describes the problems and how they are overcome.

Thanks to Universe Today: When Will We Hear From Curiosity?

Curiosity’s landing site

Here’s a computer-generated view of Mars’ Gale crater as if seen from an aircraft north of the crater. Because of its history, 96-mile wide Gale Crater crater landing site is an ideal region for exploration of the planets history.

It has thick exposed sections of layered sedimentary rocks with a wet history. Joy Crisp, Mars Science Laboratory Deputy Project Scientist from NASA’s Jet Propulsion Laboratory said:

“The rock record preserved in those layers holds stories that are billions of years old — stories about whether, when, and for how long Mars might have been habitable.”

For further information go to Image of the Day –NASA’s Gale Crater Mars Landing Site for Tomorrow’s ‘Search-for-Life’ Mission.

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Going for gold – on Mars Ken Perrott Aug 05

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Artist’s impression of Curiosity Rover on Mars. Credit: NASA

I know Kiwi readers are going to have a hard time dragging themselves away from TV coverage of the London Olympics – and our current ranking in the medal tables – but it’s worth putting in an effort early Monday evening for the planned landing of Curiosity on Mars. This is scheduled for 5.31 pm New Zealand time – between the reruns of New Zealand Olympic triumphs on afternoon TV and live coverage of the new days activity in the evening.

There will be a number of sites streaming live coverage, but the NASA TV  is a safe bet. When I say live – it will be live coverage of the the scientists and engineers behind the attempt, and their reaction to incoming data. There is a camera on board the probe which will record video but that won’t arrive on earth for a few days. But those scientists and engineers are going to be pretty emotional – it will be a bit like one of those attempts at Olympic gold medals we have followed lately.

I imagine that space enthusiasts around the world will be organising their own parties and venues to follow coverage. NASA coverage will even be broadcast publicly in Times Square, New York. OK, landing is at 1:30 am local time – but they say New York is the city that never sleeps.

My earlier post Seven Minutes of Terror has a video showing the complexity of the landing operation. There is obviously a large chance of failure, because much of the landing technology is new. This will add  to the excitement and tension of the video coverage.  If successful, Curiosity will be largest rover yet to land on Mars. This image gives some idea of its size

Credit: NASA

It’s really a mobile laboratory and  will search for any evidence of past or present habitable environments in the Gale Crater area. Curiosity has mast-mounted instruments for surveying its surroundings and identifying potential sampling targets. Instruments on its robotic arm will enable close-up inspections. Sample of rock, soil and atmosphere will be analysed by instruments inside the rover. Even during its descent sensors on the heat shield will collect information on the atmosphere.

Curiosity’s initial planned programme provides for 1 year of investigations, and may be extended depending on funding and performance. It’s going to be fascinating to see what this rover discovers. Discovery of life, or potential habitats for life, or even evidence of past life will create wide interest. But even negative results will give valuable insight into the similarities and differences  between early Mars and early earth.

Let’s not forget that there is always a large team behind space probes and rovers like this. The photo below showing 2/3rds of the team behind Curiosity give some idea of its size.

Credit Allen Chen: @icancallubetty

And for those who love toys – Mattel Inc., who manufacture a die-cast line of Hot Wheels toy cars, is ready to release the car-size Curiosity as its latest 1:64 scale miniature in September. The Hot Wheels “Mars Rover Curiosity” set is part of Mattel’s assortment of 247 toy cars for 2012.


For posts on the landing and work of the last Mars lander see:
Good luck Phoenix!
Phoenix has landed!
Working on Mars

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Emotional time for Shuttle fans Ken Perrott Apr 20

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Click to enlarge

There have been some great photographs online showing the last flight of the Shuttle Discovery  atop a modified Boeing 747 Shuttle Carrier Aircraft. Headed to its resting place as an exhibit at the Smithsonian’s National Air and Space Museum Udvar-Hazy Center.

This is one of my favourites.

Thanks to Astronomy Picture of the day (2012 April 19 – Discovery Departs).

A fuzzy photo of the sun Ken Perrott Mar 22

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But a great one, when you realise who took it and from where.

It’s actually a shot of the transit of Mars’s moon Deimos, (the smallest and outermost one) across the face of the sun. Photographed from the surface of Mars by the rover, Opportunity, on March 4, 2004.

Deimos – photographed by he Mars Reconnaissance Orbiter.

 

Deimos is only about 12.4 km in diameter – pretty small. So it’s an amazing photo – especially when you realise that the rovers weren’t actually designed for this sort of thing.

And here’s an artist reconstruction of the rover Opportunity on Mars.

Artist’s reconstruction of Rover on Mars. Credit: Wikipedia

Thanks to An Astronomical Photo-Op – Brad BlogSpeed.

Mindboggling Ken Perrott Feb 27

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Click image for larger version

Douglas Adams says in The Hitch-hikers Guide to the Galaxy:

“Space is big. Really big. You just won’t believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.”

The immensity of the galaxy almost seems beyond human comprehension. But this image does start to bring it home to me. It shows the extent of penetration of human radio signals into our galaxy since we have had radio. It’s that small blue dot, 200 light years in diameter, you can see in the enlarged section.

And our galaxy is only an extremely small and irrelevant part of the universe.

Christmas gift ideas: Working on Mars Ken Perrott Dec 12

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Books are ideal Christmas presents. And as I am spending some time dealing with family business I thought reposting some of my past book reviews over the next few days could be useful am repeating some of my past book reviews.

This is ideal for anyone interested in exploration of the solar system. And topical with the latest US Mars probe, Curiosity, safely on its way to Mars.


Book Review: Martian Summer: Robot Arms, Cowboy Spacemen, and My 90 Days with the Phoenix Mars Mission

Price: US$18.16; NZ$42.97; eBook NZ$20.95
Publisher: Pegasus (April 15, 2011)
ISBN-10: 1605981761
ISBN-13: 978-1605981765

This book describes Andrew Kessler’s experience when he left home and went to live on Mars. Well – almost. As he describes it:

’I spent three months in mission control with 130 top NASA scientists and engineers as they explored, photographed and dug up Mars. I was the first outsider ever granted unfettered access to the physicists, biologists, chemists, geologists and rocket scientists in the control room of a planetary mission to Mars. . . . For 90 days, I sat with the crew of the Phoenix mission working to explore the Martian arctic. Martian Summer is my non-fiction account of the strange life inside mission control and the people behind digging for dirt on Mars.’

This was possible because of an initiative by Peter Smith, Head of the Phoenix Mission. He organised to bring Kessler on to the team to provide some of the science outreach. Kessler had co-produced Mars: The Quest for Life, a Discovery Channel documentary about the mission. He was now ’embedded’ into the team at the University Of Arizona in Tucson for the 90 days of the early Phoenix programme ’Martian Summer’ is the result.

Phoenix Mars Lander

So the book is about the scientists and engineers in the team handling the Phoenix Mars Lander which landed on Mars May 25, 2008. It’s about the people actively involved in today’s exploration of Mars, and their work. Given the problems and cost of manned space exploration by interplanetary and planetary robots is currently the only game in town. The vehicles, and the teams running them, comprises modern interplanetary discovery.

’Martian Summer’ is a non-fictional, almost historical, account. But it has its fair share of excitement, frustration, stress, personality conflict, bureaucratic problems, financial problems debate and scientific discovery. Anyone who has worked in a scientific research programme will recognise the general problems.

I have worked in a scientific institute so know they can provide plenty of human interest stories. With strong characters, human frailties, comedy, sex, scandal and murder – as well as science. Personally I think they could be the basis of good TV soap operas.

But interplanetary research using robots has its own unique set of difficulties. And the Phoenix Lander compounded these with its own set of problems.

Mars sol vs Earth day

Depending on where it is in its orbit Mars is between 75 and 375 km from the earth. Obviously that meant a 10-month delay between the launch and Mars landing. But it also meant that communication with the Lander involved at least a 15-minute delay (or a ’round trip’ of 30 min) — just because of the speed of light. On top of that communication relied on relay by the Mars Orbiter, a satellite in orbit around Mars. So communicating with, and controlling Phoenix, was a complicated and long-winded affair.

The small memory (100 MB of flash memory) aboard Phoenix for storing new commands and collected data was another limit. Memory was expensive when the Lander was designed. Phoenix was basically the spacecraft built for the Mars Surveyor Program 2001 Lander. It contained scientific instruments from the Mars Polar Lander. Both those missions were unsuccessful and the name Phoenix was chosen because the mission was created from the embers of earlier Mars endeavours.

There was a large risk of losing data and power availability depended on sunlight producing another important limit. Temperature needs of the instruments on-board Phoenix limited operations to the Martian daytime and they required a power-consuming warming period before data collection.

As if that wasn’t enough there is a misfit between the Martian day (called a sol) and the earth day — 24 hours and 40 minutes compared with 24 hours. Doesn’t seem much but it meant the team had to work according to the Martian sol. So each individual was living a Martian sol instead of an earth day. They came to work at strange times, had blacked out windows in their workplaces to avoid confusion, ate, slept and celebrated at strange times, etc. The mismatch between the earth day and Martian sol meant they worked in a continuously changing time zone (and suffered long-term ’jet lag’) over a 40-day cycle. They effectively lost one earth day every 40 days.

And the unusual time shift can be a source of psychological and health problems. A Counter Fatigue Group of psychologists and physicians monitored and studied the teams. Partly to help, partly for research. And one result was the common presence of bottles of urine being passed on to monitors.

Management nightmares

The whole management of the Phoenix Lander was complicated enough without progressively shifting times zones and permanent jet lag. One team handled the upload of new commands and work plans for the Lander. Another handled the download of collected data. Both these had to fit in with the Mars Orbiter and the sol/night cycle at the Lander. Then there was the work of coding new commands. This also involved working with the sister Lander in the sand pit at Tucson – an on-site construction modelling the Mar’s landing site for testing each planned action. And that itself had problems because of the different gravity on Mars.

Then there was the science. Decisions were needed about where to collect samples using the robotic arm, and what instrument to deliver them to. And depending on results (and bureaucratic demands) plans had to be changed and new code written. Often under the pressure of deadlines.

The new discoveries

Many readers will be familiar with the new discoveries made by the Phoenix Mars Lander. The discovery of solid ice below the soil surface. The unusual presence of perchlorate in the soil. Soil nutrients. Observation of snow and clouds. Liquid water on the Lander legs. The unusual flow properties of the soil. And so on.

These discoveries were the outcomes of the mission approach — to look for water and evidence of its past presence. Mission leader Peter smith has reported some of these findings in a scientific paper (Smith, Peter. ’H2O at the Phoenix Landing Site.’ Science. 3 July 2009: Vol. 325, no. 5936, pp. 58-61).

Problems

Kessler also outlines many problems the team had to confront. Electrical shorts on the Lander deck interfering with operation of some of the instruments. Jamming of the doors on the TEGA — the Thermal Evolved Gas Analysers (apparently because of inaccurate machining of parts replaced just before launch). Early inability of sample transfer from the scoop into the ovens. A bureaucratic demand from NASA to get a sample of ice rather than rely on observations which effectively lost 23 sols of sampling time. Automatic ’safing’ of instruments — defaulting into ’safe’ mode when actions went outside preset parameters or unforeseen obstacles were met. And so on.

Each problem meant long hours of rewriting code, replanning work and testing on the sister Lander in the sand pit at Tucson, and transmission of new work plans.

I guess all this is the reality of today’s planetary exploration. Hands-on exploration – but hands-on from a distance in time as well as space.

Don’t treat soil like dirt!

One bitch I have as someone who has researched soil chemistry — why call it ’dirt?’ The NZ Soil Science society had an important motto – ’Never treat soil like dirt.’ So it surprised me to hear scientists on the Phoenix team at the time talking about ’dirt’ samples. The book used ’soil’ fewer times than ’dirt.’ Sure, technically the term for Mars is ’regolith.’ But why use ’dirt?’

And the bloody acronyms the US Space programme loves. Kessler refers to an ’acronym dictionary.’ He says ’Yes it exists. And I love it.’ Seemingly he found it necessary in getting to grips with some of the regular talks given by team members (he described one as a ’nonsensical list of acronyms’). I just wish he had provided this dictionary in the book. Acronyms may be OK for people working together everyday on the same problems and instruments — but not for most readers. At times I was unsure which instrument he was referring to, or which team was presenting information. Perhaps he could have used the full terms more often.

Here are just a few examples of the over 30 acronyms I found. Instruments on the Lander included the TEGA (Thermal Evolved Gas Analyser), AFM (atomic force microscope), WCL (Wet Chemistry Lab), MET (Meteorological station), RA (robotic arm), ISAD (Icy Soil Acquisition Device), SSI (Surface Stereo Analyser), LIDAR (Light Detection and Ranging Instrument) and MECA (Microscopy, Electrochemistry, and Conductivity Analyser).

Testing was done at the PIT (Payload Interoperability Testbed). Non-US Team members had restricted access to some information because of ITAR (International Traffic in Arms Regulation). And EOS was the End of Sol!

Mind you, I thought naming samples and sample sites was endearing. Refreshing to see reference to the “Rosey Red” and “Baby Bear” samples!

Conclusions

I enjoy realistic stories about science and much prefer them to the common fantasy sci-fi. So I welcomed the chance to review this book.

I found the writing a little over-enthusiastic in parts — especially at the beginning. But once Kessler got into the details of the science, the problems and the discoveries, the account was absorbing.

Just as you would expect in a good soap opera.

If you like science stories and realistic science fiction you will enjoy this book. Especially if interplanetary exploration appeals.

See also: Key publications

H2O at the Phoenix Landing Site
Abstract | Full Text
Smith, Peter et al

Detection of Perchlorate and the Soluble Chemistry of Martian Soil at the Phoenix Lander Site
Abstract | Full Text
Hecht, Michael et al

Evidence for Calcium Carbonate at the Mars Phoenix Landing Site
Abstract | Full Text
Boynton, William et al

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