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Space and Humanity in the 21st Century – Part 5: Going the Distance to Pluto and the Kuiper Belt

Published on May 17, 2012 by in 21st century technology, Space

To Pluto and the Kuiper Belt with New Horizons

I grew up like most of you with the certainty that our Solar System had nine planets revolving around the Sun. But Pluto, the ninth wasn’t discovered until 1930, nineteen years before I was born. And now that I am 63 we are back to before 1930 with eight planets. But we have added a new category called dwarf planets of which Pluto is one of possibly 1,000 or more. And Pluto is the object of New Horizons, a spacecraft launched in 2006 and arriving in the dwarf planet’s vicinity by 2015.

Pluto doesn’t look or act like any of its gas giant planet neighbours. Its orbit is not circular and is inclined at an angle that has it rising above and below the orbital plain of the other planetary bodies in the Solar System. It is so far away from the Sun that it is easier to describe the distances using a different measurement than kilometers or miles, in this case Angstrom Units or AUs. One AU equals the distance between the Earth and the Sun. When Pluto is closest to the Sun it is 30 AUs. When it is furthest away it’s 50 AUs from the Sun. When New Horizons arrives near Pluto in 2015, the dwarf planet will be approximately 31 AUs from the Sun and 4.8 billion kilometers (3 billion miles) from Earth. A message sent from New Horizons in 2015 will take four hours to reach us, more than two-and-a-half times longer than messages sent by Cassini from the vicinity of Saturn.

Other than the great distance and odd shaped orbit, what else do we know about Pluto? In size Pluto (2,274 kilometers, approximately 1,400 miles in diameter) is smaller than our Moon, Io, Europa, Ganymede, Callisto, Titan and Triton. Its surface bears a slight resemblance to Iapetus, the moon I described as bipolar in my blog about Cassini. Why bipolar because from Earth-based telescopes and Hubble we can see significant contrasts in light and dark features on the dwarf planet’s surface.

We have measured the surface temperature of Pluto at between -210 and -235 degrees Celsius (-346 to – 391 Fahrenheit). The axis of Pluto appears to be acutely inclined similar to Uranus. Composition appears to be a mixture of rock and water ice (70/30). We have identified nitrogen ice, solid methane, ethane and carbon monoxide in the brightest surface regions but have yet to figure out the surface composition of darker areas. Pluto’s tenuous atmosphere is believed to primarily consist of nitrogen as it is here on Earth with lesser quantities of methane and carbon monoxide. The atmosphere may freeze when Pluto is furthest away in its orbit but New Horizons will arrive while the atmosphere is in a gaseous state.

Charon, Pluto’s primary moon was discovered in 1978. It is unusually large as moons go when compared to Pluto with a diameter of 1,206 kilometers (approximately 750 miles). That makes it the largest moon in relationship to its companion of any Solar System object. Pluto and Charon rotate synchronously keeping the same face towards each other.

The images above are of Kuiper Belt Objects, icy sub-planets that have only recently been discovered from Earth-based telescopes and the Hubble Space Telescope. Note that Pluto is today classified as a “dwarf planet” by scientific orthodoxy as are many other Kuiper Belt Objects.                                          Source: The Encyclopedia of Science

New Horizon’s Mission Not Just Pluto

The mission to Pluto is a rendezvous and flyby. Why? because Pluto’s gravity is so low that entering orbit around it would be very difficult. The benefit of a flyby approach may be the opportunity to study other Kuiper Belt objects that New Horizons discovers after passing by Pluto. The Kuiper Belt resides outside the orbit of Neptune and is often described in similar terms to the Asteroid Belt between Mars and Jupiter. The difference, however, is the Kuiper Belt, first discovered in the mid-1990s, features many much larger objects that we classify as dwarf planets. See some of the more recently discovered ones in the illustration above. We think most Kuiper Belt objects consist of water ice and rock similar to Pluto. Our current estimates suggest the Belt is populated by at least 1,000 objects of which many can be classified dwarf planets. With odd-shaped orbits and orbital inclinations it will be a challenge for the mission team on Earth to find and image Kuiper Belt Objects let alone image Pluto in the faint sunlight of the outer Solar System. And to add to the mission tasks, when New Horizons launched Pluto was known to have a single moon. Since then Earth-based telescopes and the Hubble have identified three more. So that means trying to capture these new moons with on board cameras and sensors.

As in the Galileo and Cassini missions to Jupiter and Saturn, New Horizons has a payload of scientific instruments (see the image and table below) that include spectrometers, telescopes, infrared and ultraviolet imagers, magnetometers and other sensors. These will be used to study Pluto, its atmosphere, image and map its surface, study the interaction of the dwarf planet and its atmosphere with the solar wind and detect the presence or lack of a magnetosphere. With solar energy and light at a level 1/1,000th of space near Earth, New Horizons uses an RTG fuelled with plutonium dioxide to provide heat and power for the instrumentation.

While on its way to Pluto, New Horizons has been doing science in preparation for its ultimate destination. This has included a rendezvous with Jupiter, training its seven cameras and sensors on that planet and its four largest moons. The spacecraft has sent the first images of Pluto and Charon back to Earth as it has crossed the orbits of Uranus and Neptune. When it finally arrives in three years it will, as have all our other outer planet robotic spacecraft, alter our knowledge of the Solar System once again. We will learn more about the worlds of the outer Solar System and identify new Kuiper Belt Objects to add to our growing collection of neighbours.

 
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Space and Humanity in the 21st Century – Part 4: Robots to Saturn and a Landing on Titan

Published on May 16, 2012 by in 21st century technology, Robots, Space

What has compelled us to return to Saturn after the voyages of the robotic spacecraft, Pioneer and Voyager, in the latter part of the 20th century? Yes, Saturn with its rings was mysteriously beautiful. Like Jupiter it was a miniature Solar System with many moons of which Titan, the largest, appeared as an orange-shrouded mystery with a passing resemblance to a primordial Earth. Was it the outward urge or the pure science that led to Cassini, the robotic spacecraft that to this day continues to unravel Saturn’s mysteries and beauty?

For whatever the reason the voyage of the joint mission of Cassini and its companion Titan probe, Huygens, continues to amaze us with imagery and telemetry on the Saturnian system. NASA, the European  Space Agency and the Italian Space Agency developed the technology that was launched in October of 1997. Seven years later the spacecraft arrived at Saturn entering into orbit around the planet. In 2005 the Huygens probe landed on Titan’s surface. Huygens transmitted images and data from the surface for a short period before falling silent. In its descent and landing we gained a great deal of knowledge about Titan.

Today Cassini continues to operate its cameras, spectrometers, magnetometers and analyzers as it swings around the planet visiting the moons and giving us spectacular images of the entire system including Saturn’s amazing rings.

The Challenge of Getting to Saturn

The technique deployed by Cassini to get to Saturn involved gravity assisted acceleration. In the diagram below you can see the indirect route taken. It involved a Venus flyby in 1998 and then Venus, a second time, followed by Earth in 1999. Next was a close encounter with Jupiter in 2000 and from there it travelled to Saturn arriving in 2004. Each planetary flyby provided a gravity assist to Cassini gaining speed with each pass. Total flight distance equalled 3.5 billion kilometers. This method allowed Cassini to save fuel and made it possible to keep its launch weight under six metric tons. Without gravity assist the spacecraft would have required a much larger compliment of fuel.

Using the gravity of other Solar System objects to provide a spacecraft with the speed necessary to reach its destination is a technique first proposed by scientists in 1961. Called gravity assist, Cassini represents one of the best examples of the use of this method for propelling a spacecraft from Earth to a distant destination, in this case, Saturn. Source: The Thought Stash

Designing a Spacecraft for Long Distance Communication and Survival

Cassini had to be designed to operate with a high degree of autonomy. On average it takes one hour and 24 minutes for a transmission from Earth to reach it.  That means a 3-hour round trip between Earth and Saturn. The images Cassini transmits back to Earth give scientists a visual means of understanding the orientation of the spacecraft and its location within the Saturnian system. Instructions are then sent from Earth to orient the spacecraft’s instruments for whatever the planned objective  whether a moon, the rings or the planet itself.

With the Cassini mission planned to continue for another five years until 2017, power and fuel consumption are paramount concerns. Cassini relies on three plutonium fuelled RTGs for power and heat in the extreme cold near Saturn. As the plutonium decays Cassini slowly loses power. But it has sufficient capacity to keeps its instrumentation in operation for the foreseeable future.

Propellants are another matter. Cassini is fuelled with two types of propellants, a mono-propellant and a bi-propellant. The mono-propellant, hydrazine, is used to do small maneuvers such as positioning and alignment. The bi-propellant, a mono-methyl hydrazine with  nitrogen tetroxide has been used for course correction and other large maneuvers. When Cassini started out it had 132 kilograms of hydrazine, 1,131 kilograms of mono-methyl hydrazine and 1,869 kilograms of nitrogen tetroxide on board. Much of the fuel was spent getting to Saturn and for orbital insertion. The remainder is seldom used and as a result the spacecraft even with less than 10% of its original bi-propellant remaining can continue to fly.

What We Have Learned So Far About Saturn and its Moons

How do you sum up what we have learned from Cassini? The science and discoveries have been incredible. Here are some highlights:

  1. Saturn  exhibits two vortexes at its poles with heat from the planet’s interior welling up into monstrous thunderstorms with powerful lightning bolts. The planet’s magnetic field interacts with the atmosphere at the poles to create extensive aurora similar to those on Earth. Its atmosphere is mostly hydrogen and helium but also contains traces of ammonia, phosphine, methane and other clouds. It rains and snows on Saturn. The planet’s core (about  6,000 kilometers, 3,700 miles in diameter) appears to consist of rock and ice reaching a temperature of between 10,000 and 15,000 Celsius (18,000 to 27,000 Fahrenheit) with layers of metallic and liquid hydrogen above. The separation between the liquid and gaseous hydrogen appears undefined.
  2. Saturn’s most obvious feature is its rings. Cassini has given us data on the ring structure and discovered new rings and ringlets, as well as moons near and in between rings with some of them stealing ring particles, and others losing particles to add to the rings.
  3. The Huygens probe and Cassini have given us a picture of Titan that is both alien and familiar. Titan has rivers and lakes. Its atmosphere has clouds that produce rain. Atmospheric pressure is just slightly higher than that found on Earth. Winds sculpt the landscape with vast dune fields constantly undergoing erosion. Volcanoes erupt as well just like on Earth. But unlike Earth where water forms a liquid, on Titan with its surface temperatures of -179 degrees Celsius (-290 Fahrenheit), it is methane that fills its rivers and lakes, forms the clouds and rains down from the skies. And the volcanoes spew ice rather than lava while its dunes consist of sand-like hydrocarbon particles. Titan’s interior includes an ocean of liquid water and ammonia with volcanic out-gassing constantly replenishing its atmosphere.
  4. Cassini has doubled the number of discovered Saturnian moons with 62 the latest count. Before it arrived at Saturn we knew of 31 from Pioneer, Voyager and Earth-based observations. Moon discoveries other than Titan include:
  • a dynamic Enceladus that is geologically active with the discovery of simple organic compounds on its surface and liquid water beneath its frozen surface, making it very similar to Europa, one of Jupiter’s moons.
  • the amazing bipolar nature of Iapetus with its enormous ridge dividing the planet into a dark and bright side
  • the faint rings that surround Rhea
  • the sponge-like nature of Hyperion’s surface where material impacts punch into the porous surface and ejecta escapes the moon’s low gravity
  • the tiny moon, Aegaeon, one-half kilometer in diameter and orbiting within a segment of one of Saturn’s rings with debris from it contributing to the ring’s formation

With Cassini, we are not done yet but once the mission is over expect a return to Saturn’s neighbourhood with missions that will land and explore Titan and Enceladus.

Some of the many images from the Cassini-Huygens mission. From top left and going clockwise: Enceladus, geologically active with an ocean of water and organic molecules detected beneath its icy crust; Hyperion, looking like a piece of pumice stone rather than a moon and as porous as a sponge; Iapetus with its central ridge and contrasting dark and bright side unlike any other object in the Solar System; the rings of Saturn in ultraviolet light showing an icy progression from the inner to outermost ring; Titan's surface as seen by Huygens shortly after landing; and liquid methane rivers, shorelines and lakes on the surface of Titan, eerily similar to images of Earth. Source: NASA/ESA/ JPL

 
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Robotics and Material Science Update: When will Robots Feel?

Published on May 16, 2012 by in 21st century technology, Materials, Robots

Have you heard of oscillating gel? Researchers at University of Pittsburgh and the Massachusetts Institute of Technology (MIT) have demonstrated that this material responds to mechanical and chemical stimuli something only previously displayed by living membranes such as human skin. For robots the gel could serve as an artificial skin.

Known as Belousov-Zhabotinsky (BZ) gel, and first discovered in the 1950s, it wasn’t until the mid 1990s before experiments demonstrated the gel’s unique abilities to pulsate performing bio-mimicry. Described by scientists as “smart” or “intelligent” the actual physical and chemical response is a chemical volume phase transition resulting from external environmental changes that leads to the swelling and shrinking of the gel.

The recent experiments at MIT and University of Pittsburgh have demonstrated that the gel can be used with sensors or actuators for a number of different applications including usage in bio-medicine for drug release devices, and in robotics.

Oscillating gel is a material that can sense and respond to external stimuli. When left on their own in response to stimulus they oscillate just like heartbeats and arterial pulsations.       Source: Revoseek.com

In a robot with skin made from oscillating gel it would feel pressure and react to it through the chemical signal it would receive. In addition the gels could sense any damage they receive such as a tear or puncture and perform self-healing. Scientists are also looking at ways to use the gel to create synthetic muscles that work in combination with mechanical actuators.

Are we getting closer and closer to our Star Trek cyborg friend, Data? As the 21st century unfolds I think we are.

 
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Urban Landscapes Update: A Building That Speaks to Our Urban Future

Published on May 15, 2012 by in Cities, Uncategorized, urbanization, World Population

By the mid-21st century 6 billion of us will be living in urban environments. What will that mean for cities and the buildings in which humans live?

If current trends reflect what lies in our mid-century future then we will continue to see urban intensification with cities ever reaching upward.

Here in the Greater Toronto Area, a city of well over 5 million, a place I call my home, the city increasingly is relying on residential and commercial construction focused on multiple-residence dwellings rather than single-purpose commercial buildings and family homes.

Toronto, my home, is experiencing urban intensification with residential construction focused on increasingly taller multi-residence units. Source: Urban Toronto

But buildings are not just going to get taller. They are also going to become energy independent, carbon neutral, and capable of adapting to seasonal and daily changes happening around them by using new materials and technology.

One such building that speaks to urban landscapes in our near future is the Media-ICT building in Barcelona, Spain. Barcelona is known for its innovative architecture but this building pushes the envelope of technical advancement.

When you look at it (see below) you get an inkling that there is something very different about this building and you are right. Its features include:

  • A photovoltaic roof to power all the energy requirements of its tenants
  • More than 500 embedded smart sensors each one having its own IP address so that software can measure temperature, humidity and pressure both on the inside and outside and automatically alter the building’s material characteristics
  • An exterior membrance that consists of inflatable ETFE foil cushions kept continually pressurized to act as a sunscreen in summer when closed, and a solar energy generator in winter when open
  • Nitrogen within the foil cushions that can alter opacity by turning into a fog in response to  outside lighting conditions

Barcelona's Media-ICT Building responds to the environment around it using smart materials and sensors. Source: World Buildings Directory

The Media-ICT building’s exterior membrane is like our skin and responds to external changes in a similar way. We call this bio-mimicry because it’s almost as if the building has become a living thing.

 
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Biomedicine Update – What do A, B, AB and O mean to you? Now add Langereis and Junior to the family

Published on May 12, 2012 by in 21st century technology, Biomedicine

I’m A, Rh+. Most of us are O, Rh+. Figured it out yet? I’m talking about our blood. As a regular blood donor I have learned about blood types and who I can give blood to and who I can’t. But for most of us who are not donors this remains a mystery. Well it turns out that even I as a donor only know half the story and it’s an interesting one.

Our human population globally shares 4 major blood types. In some countries these types are referred to with different classifications (in Russia, for example, they are referred to as 1, 2, 3 and 4) but generally through most of the world they are defined as A, B, AB and O. Blood that is classified as A contains an antigen or protein that makes it compatible only with other people with A or AB blood types. Blood that is classified as B contains another antigen that works only with B and AB blood types. Those with AB blood contain two antigens that makes it possible only to receive blood from another with AB blood. Those with O blood have no antigen and can therefore be compatible with any other blood type. When blood isn’t properly type matched the presence of an antigen can lead to a dangerous reaction in the person receiving the blood.

Rhesus monkeys share many of our biological characteristics. The Rh protein is named after them and when present in blood is referred to as a positive, or Rh+. The absence of Rh protein is negative or Rh-. So all blood types are a combination of these four different types plus the existence or non-existence of Rhesus proteins. Hence we have A+, A-, B+, B-, AB+, AB-, O+ and O-. This has been our general understanding of the major blood groups since Karl Landsteiner, an Austrian, first made the discovery in the 1890s, and since our discovery of the Rhesus protein in the first half of the 20th century.

Until recently we classified four main blood groups as they appear in the illustration above plus the absence or presence of Rhesus proteins, giving us 8 in total. Today we know of 32 other proteins that differentiate blood types and suspect 10 to 15 more.

But the science of blood typing has led to further refinements since the mid-20th century and up until a few months ago we had identified 30 variable proteins. Some of these go by such interesting names as Duffy, Kidd, Diego and Lutheran. Now we can add two more named Langereis (Lan for short) and Junior discovered by the combined work of researchers at the Japanese Red Cross Osaka and Hokkaido Blood Centers, the University of Vermont and the French National Institute for Blood Transfusion in Paris. Right now both of these new blood group proteins are considered very rare but with their identification routine screening for the proteins can become a global standard.

Matching blood proteins is extremely important for ensuring successful organ transplants. Any one of these blood proteins in the donor could, if incompatible with the recipient, lead to organ rejection as the body automatically creates antibodies to defend against what is seen as a foreign invader.

Currently populations most susceptible can be found in Japan and among European Roma who are at higher risk because they do not have the Lan and Junior proteins. Scientists believe there are more unknown blood types, as many as 10 to 15, still to be discovered.

 
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Biomedicine Update: Ceramic Nanotechnology in a Breathalyzer to Uncover Disease

Published on May 11, 2012 by in 21st century technology, Biomedicine, Nanomedicine

Blow into the Single Breath Disease Diagnostics Breathalyzer and if you get a green light you are good to go but if the light turns red it means you need to see your doctor. That is how this new invention works. Developed by a team within the Department of Materials Science and Engineering at Stony Brook University, New York, led by Professor Perena Gouma, this gas detection device uses a sensor chip coated with tiny nanowires resembling spaghetti. The nanowires can detect minute amounts of chemical compounds in a person’s breath including disease marker gases.

Professor Gouma is also director of the Center for Nanomaterials and Sensor Development at the university and it is this particular expert knowledge that has led to the development of what will become a first response detection system available over the counter for under $20.

The manufacturing process for creating the micro-spaghetti nanowires is called electrospinning, a process that involves shooting a liquid ceramic compound through a syringe into an electrical field. The electrospun fibers crystallize as tiny threads that are captured on an aluminum backing.

The micro threads seen in this picture are electrospun fibers that are used to capture molecular indicators of disease. Source: Stony Brook University.

Electrospinning is a technology of the 21st century. It is simple and versatile allowing manufacturers to easily fabricate nanostructures on an industrial scale for use in electronics, photonics, pharmacology, and chemical engineering. A single syringe of liquid ceramic can produce a nanowire that can stretch from the Earth to the Moon. Different nanowires can be designed to be sensitive to specific molecules. A particular nanowire could detect nitrous oxide, associated with asthma and stress-related illnesses. A nanowire could be used to detect ammonia, a marker for kidney disease, or acetone, indicating diabetes. Nanowires could be used to detect the presence of viruses, e-coli, anthrax, salmonella, high cholesterol levels and different cancers.

Breathalyzers have been around for awhile. So why is this device worth talking about? Because it takes the technology from institutions like hospitals, or police departments, and turns it into a mass market, consumer product. The device is still undergoing testing but we should soon see breathalyzers using this technology on drugstore shelves.

 
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Space and Humanity in the 21st Century – Part 3: Robots to Jupiter

Published on May 10, 2012 by in 21st century technology, Robots, Space

The Grand Tour whet our appetite for learning more about planets and asteroids beyond our closest neighbour Mars. To once more explore Solar System bodies at extreme distances technology needed to be designed with its own intelligence to operate autonomously and reliably over long duration in the cold of interplanetary space. Remarkably the robotic spacecraft NASA designed to achieve these long duration flights has performed optimally.

With Jupiter our first destination, followed by Saturn, two members of the Asteroid Belt, and Pluto and Charon, these voyages straddled the end of the 20th and beginning of the 21st century. So let’s begin with our return to Jupiter on a spacecraft named Galileo and then discuss other missions in progress or planning and why we keep going back to this gas giant.

What compelled us to return to Jupiter after the successes of the Pioneer and Voyager missions? There were lots of unanswered questions about Jupiter, when it formed, where it formed whether it has a solid core and its structural composition, and which if any of its moons had liquid water and the ability to sustain life. We wanted to understand how one moon, Io, could be constantly going through the throws of reforming its crust with more active volcanoes than any other body in the Solar System including Venus.

Galileo – A Voyage of Discovery That Changed Our View of Jupiter and its Moons Forever

The Galileo mission was designed to address some of these questions. A spacecraft designed in the 1980s, it took nearly six years from its launch in 1989 to get to Jupiter. Its route took it first by Venus once and Earth twice before developing the gravity-assisted speed necessary to coast past Mars and through the Asteroid Belt to Jupiter.

While on route it rendezvoused with two asteroids, first Gaspra in 1991 and later Ida in 1993. While passing Ida it captured a picture of the asteroid and its accompanying moonlet named Dactyl. A year later on approach to Jupiter it bore first-hand witness to the destruction of Comet Shoemaker-Levy as it impacted the planet.

Galileo finally arrived at Jupiter in December 1995. It launched a companion atmospheric probe on July 13, 1995. The probe descended through 200 kilometers (124 miles) of the planet’s outer atmosphere collecting data on local weather conditions – for July 13, a dry day with a few clouds and distant lightning. As the probe descended further it experienced winds exceeding 720 kilometers (450 miles) per hour and finally vaporized in the intense heat of the atmosphere after 61 minutes of transmission.

Galileo’s path around Jupiter took it in long elongated orbits around the planet, each averaging about two months. The orbits allowed the spacecraft to sample Jupiter’s magnetosphere in different locations while performing close rendezvous with Jupiter’s many moons. After 35 of these orbits and almost eight years of operation in the planet’s vicinity Galileo was instructed to self-destruct in the Jovian atmosphere to avoid a potential contaminating impact with the moon Europa.

What answers did Galileo give us to the questions we had about Jupiter and the Jovian system?

  1. It answered the question about the moons in discovering evidence of a saltwater ocean under Europa’s icy crust and liquid bodies of saltwater on two other moons, Ganymede (the largest moon in the Solar System) and Callisto.
  2. It gave us a better understanding of the gravitational forces of Jupiter responsible for the active volcanic and tectonic processes witnessed on the moon, Io. Such forces were little understood until scientists took a close look at the lava lakes and molten rock flows of this Jovian moon where temperatures exceeded 1,700 degrees Celsius, hotter than any place in the Solar System other than the Sun.
  3. With its probe on onboard science instruments we got our first good picture of conditions within Jupiter’s atmosphere. We studied the stationary storm, Jupiter’s Great Red Spot, the planet’s auroras, its magnetosphere, and its tenuous dark rings.
  4. In the discovery of larger than anticipated concentrations of argon, krypton and xenon, noble gases, it raised more questions about when and where Jupiter originated.
  5. And it raised a whole bunch of new questions about Jupiter’s largest moon, Ganymede, a moon with its own magnetic field suggesting a dense liquid metal core similar to that found inside Earth. Even more surprising Galileo also discovered that Ganymede’s tenuous atmosphere contained O1 and O2 molecular oxygen as well as O3 (ozone).

Galileo provided us with a new perspective on the Jovian system as it repeatedly flew by Jupiter's many moons. Seen here at the top is the moon Io with the planet in the background. Io is the most tectonically active place in the Solar System. On the bottom left is Ganymede, larger than the planet Mercury. And on the bottom right is Europa, the size of our Moon, with an active ocean underneath a water ice surface crust that displays cracks and large flow patterns generated by inner tidal movement. Source: NASA/JPL/ U of Arizona

Because of these discoveries and the many still unanswered and new questions that arose from Galileo’s mission, Jupiter is once again to be visited by a new spacecraft, Juno, that will focus on the planet exclusively. The Juno mission will be followed by a new robotic spacecraft, Juice, with a mission to study the Jovian system and in particular its ice moons.

Juno – Dissecting Jupiter to Understand How the Solar System Formed

Jupiter is the largest planet in the Solar System. Its mass is greater than all the other planets combined. Scientists theorize it was the first planet to form out of the nebula that condensed to form our proto-Sun and its planetary companions. What is not known is where Jupiter formed? The presence of large quantities of noble gases as found by Galileo suggests that Jupiter may have formed much further out than its present position as fifth planet from the Sun. Juno, the next mission to Jupiter may provide us with answers and help us learn more about the earliest period in the Solar System’s formation.

In returning to Jupiter with Juno the goal this time is to focus on the planet itself and not the larger Jovian system. Scientists hope to learn more about the origins of the Solar System by studying Jupiter, its composition, whether it has a solid core, and the mechanism behind its powerful magnetic field.

Our current theories on Jupiter's internal structure propose that the planet has a solid core with a liquid metallic hydrogen internal mantle, an external mantle hydrogen and helium in both liquid and gaseous form and an atmosphere containing water, carbon dioxide, methane and other trace gases. Source: Enciclopedia do Espaco e do Universo

Juno is a very different spacecraft than Galileo. It is solar powered. Galileo was powered by a Radioisotope Thermal Generator (RTG). In choosing solar over RTG the spacecraft designers have built a significant solar array with three panels, each 2 meters (6 1/2 feet) wide and 9 meters (almost 30 feet) in length. The size of this array is significantly larger than any previous robotic spacecraft. Why? Because sunlight near Jupiter is 27 times weaker than sunlight near Earth.

In addition the spacecraft is designed to fly with its solar panels always sun facing to maximize its ability to power the instrumentation package on board (see image below).

Upon its arrival in 2016 Juno will enter a close polar orbit around the planet taken it within 100 kilometers of the cloud tops. In this way Juno will be less exposed to the Jovian magnetosphere while it directs its scientific instruments at studying the planet below. After 32 to 33 orbits taking approximately one year the plan is to deorbit the spacecraft to burn up in the atmosphere in October 2017.

Juice – Europe’s Contribution to Exploring the Jovian System

The Juno mission is not our last visit to the vicinity of Jupiter. Other missions are planned including a lander with technology to drill into the surface of Europa to sample its subsurface ocean, and a new mission from the European Space Agency (ESA), named Juice, planned for a launch in 2022 with arrival at Jupiter by 2030.

Juice stands for Jupiter Icy Moons Explorer. The mission will study Europa, Ganymede and Callisto. The spacecraft will make several flybys of these moons while doing further studies of Jupiter’s atmosphere and magnetosphere and how the latter interacts with its moons. The plan includes a final rendezvous with Ganymede with Juice entering into orbit around that moon in 2032.

In choosing Ganymede as its final destination Juice will study its atmosphere, icy surface, internal structure and subsurface ocean as well as its unique magnetosphere.

Our next stop in our exploration of the outer planets – Saturn.

 
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Energy Update: Are Wind Farms Contributing to Global Warming? – Sorting the Fact from the Fiction

Published on May 9, 2012 by in Climate change, Energy, Environment, Renewable, wind power

A recent headline caught my eye, “Wind farms make climate change WORSE: Turbines actually heat up local areas.” This appeared in the London, England based Daily Mail. The article reported that air temperatures around four of the world’s largest wind farms had incresed over a decade by 0.72 degrees Celsius ( about 1.3 degrees Fahrenheit). It went on to provide a comparison to global temperature rise stating that Earth’s average temperature comparably had warmed by only 0.8 Celsius since 1900. Fox News picked up the article with its own headline, “Wind Farms are Warming the Earth, Researchers Say,”  It therefore implied that wind farms were contributing to  global warming. Is this good scientific analysis or an anti-wind farm statement?

Are wind turbines contributors to global warming? Only if you believe bad research and alarmist media. Source:These headlines are meant to be alarmist. They are a canard. Source: MAYYSOLAR 2012

Measuring local temperatures in a few specific areas, whether near wind farms, or near coal-fired power plants, does not provide evidence that wind farms or coal-fired power plants contribute to global warming, cooling or global anything. What is actually being measured is the local impact of machinery in operation and the movement of air caused by rotating blades that affects circulation in the immediate vicinity. Waste heat from a wind turbine has to go somewhere.  Air currents are affected by turbines and may alter local ground temperature conditions either by making them warmer or cooler. (We’ll say more about this later.) On the other hand CO2 from coal-fired power plants does contribute to rising CO2 levels in the atmosphere and there is a direct correlation between global warming and elevated atmospheric CO2.

The original research that led to these screaming headlines comes from State University of New York – Albany where researchers conducted a study analyzing satellite data from 2003 to 2011 over large wind farms in Texas. The researchers concluded that wind farms were contributing to local warming of the air at ground level. The researchers stated that if these wind farms were even bigger they could impact local weather and climate. The operative word local should be noted.

It is worthwhile to compare this study to another reported in December 2010 in Discovery News in an article entitled “Wind Turbines Increase Crop Growth.”   A University of Colorado study, as reported in this article, concluded that wind turbines  improve the growth of nearby corn and soybeans by keeping the crops dry and reducing temperature extremes. The increased air movement caused by the turbines cools the crops just as a fan makes air feel cooler in a room on a hot day. The article stated that wind turbines are like trees in that they modify local weather conditions. I suspect that the Daily Mail and Fox News will soon provide us with a headline that states, “Trees Contribute to Global Warming – We Need to Cut Them Down.” The truth is that any time you operate machinery its emits heat. Put a lot of it in an area and the air heats up. Operate a fan in a room and it changes air flow which moves warm and cool air around. How difficult is this to understand?

Finally it should be stated that wind farms represent a renewable energy source making it possible to rely less on fossil fuel burning, CO2 emitting power plants for our energy needs. Whereas we know that rising CO2 correlates to rising temperatures on a global scale.

 
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Space and Humanity in the 21st Century – Part 2: Orbiters, Rovers and Landers on Mars….Continued

Published on May 9, 2012 by in 21st century technology, Robots, Space, Water

By the end of 2012 Mars will have many human-built robots on its surface, in orbit around it, some artifacts and some operational.

In our last blog we talked about the compelling question we are trying to get the answers to in visiting Mars. What is our ultimate goal? Is it creating a human colony on the planet? Is it exploitation of potential Martian resources for use by humans on Earth? Or is it the science and the potential of discovering life elsewhere in the Universe that is driving our interest?

In 2003 Europe joined the United States with its first successful orbiter. Meanwhile Spirit and Opportunity were joined by a third lander in 2008, a lander with a robotic arm that was designed to find subsurface ice and test the chemical properties of its discovery.

So let’s continue the story about the unwrapping of the mysteries of Mars beginning with a new space agency player joining the search for life on Mars.

Mars Express

The European Space Agency (ESA) built its own multi-robot mission to Mars and launched it in June 2003. The spacecraft, an orbiter named Mars Express, included an additional small lander, Beagle-2, named after the ship upon which Charles Darwin made his epic voyage of discovery. The orbiter included a high resolution stereo camera plus a wide range of scientific instruments for mapping and studying surface and atmospheric composition.

Beagle-2 unfortunately failed in its landing attempt but Mars Express has been a great success working well beyond its one Martain year mission goal. It continues to provide images and telemetry to this day contributing to our further understanding of the geography and geochemistry of the planet.

This perspective image was created using the High Resolution Stereo Camera on Mars Express. It is colour coded by elevation. The image is of Tharsis Tholus, an 8 kilometer-high volcano. The relief has been exaggerated by a factor of three. Source: European Space Agency

Phoenix

The Phoenix Mars Lander was designed to study the circumpolar region of Mars. Why?

In 2002 instruments on the Mars Odyssey orbiter had discovered large quantities ice under the surface soils in the northern hemisphere of Mars. Phoenix was designed to “follow the water.” Its job was to sample subsurface ice and report on soil chemistry in the presence of ice.. Equipped with a robotic arm tipped with a shovel (see image below), and an on board set of experiments designed to do chemical analysis, Phoenix would give us a better picture of the potential for existing life on the planet.

Phoenix also had on board equipment to provide us with daily Martian weather reports for the northern arctic plain. Launched in August 2007, Phoenix touched down in May 2008. The lander mission in this harsh environment was scheduled to last ninety days. It exceeded this by almost two months before the photovoltaics (see the solar panel in the image below) could no longer gather sufficient sunlight as the northern hemisphere moved into winter.

The Phoenix Lander's robotic arm, seen in the upper right of this picture, continuously sampled Martian soils and subsurface ice throughout its mission delivering the content to the on board lab for analysis. Source: NASA/JPL/U of Arizona/ Texas A&M University

The findings of the Phoenix mission indicated the presence of liquid water with deposits of calcium carbonate left behind when the water evaporated. Deposits were attributed to precipitation in the form of snow mixing with atmospheric carbon dioxide.

The soil chemistry included perchlorate, a big surprise discovery. Perchlorate on Earth is an oxidizing chemical that strongly attracts water and provides a food source for some Earth microbes. Could the perchlorate discovery by Phoenix indicate the presence of life currently on Mars?

Finally Phoenix observed something no scientists ever suspected – Martian snowfalls leading to a build up of water ice on the surface during Martian winters in the northern arctic plain.

The Phoenix findings once more reignited the life on Mars debate pointing to a strong likelihood that if it does not exist in the present, conditions for microbes to survive certainly have existed in the recent past.

Mars Reconnaissance Orbiter

Where there is water on Earth there is life. With this in mind much of our efforts to-date in exploring Mars have continued to focus on finding water. Once such mission is the Mars Reconnaissance Orbiter, launched it 2005 and designed specifically to study Mars from this perspective.

This orbiter is the first to be completely designed to alter its configuration through phases of flight, to optimize fuel use and take advantage of aerobraking for orbital insertion manouevers. Slimmed down to weigh 2,180 kilograms (4,806 pounds) on blast off, of which more than half represented propellant for course corrections during the long voyage to Mars, the Mars Reconnaissance Orbiter arrived at the planet in 2006.

The orbiter is designed like a badminton birdie with the spacecraft using its large solar arrays as wings during aerobraking to slow it and reduce the size of each of its orbits. Components have been designed to withstand the heat generated by each aerobraking manoeuvre in and out of Mars’ upper atmosphere. Taking six months before settling into a final orbital trajectory, Mars Reconnaissance Orbiter has been in operation around Mars from 2006 to today.

During its long flight to Mars, the Mars Reconnaissance Orbiter has tested new technologies for Deep Space communication using much less power. A new navigation camera has improved the precision of interplanetary flight manouevering.

The orbiter has also deployed six different scientific instruments and two on-board scientific facilities for conducting experiments. These experiments have mapped the gravity field of Mars and during aerobraking studied the structure of the Martian atmosphere.

Since its arrival three different cameras have been providing high-resolution images of the surface geography and weather on Mars. A sounding radar produces subsurface images to detect water ice to a depth greater than one meter (39 inches). A spectrometer identifies surface minerals. A radiometer measures atmospheric temperature, levels of dust and the presence of water vapour. The mission of the orbiter originally planned for one Martian year continues to this day amassing  more data than all previous Martian missions.

What has Mars Reconnaissance Orbiter discovered?

Mars has extensive subsurface ice deposits that are subject to seasonal melting. As the orbiter has repeatedly passed over the same landscapes it has tracked these warm-season feature changes that strongly suggest evidence of salty liquid water flowing down gullies on the escarpment edges of craters.

These two pictures from Mars Reconnaissance Orbiter show the dynamic nature of the Martian environment. On the left, we see an oblique angle view of what appears to be briny water flowing down the escarpment wall of a crater. These flow features average from one-half meter to less than 5 meters in width. On the right we see a dust devil travelling across a Martian plain. This dusty whirlwind is about 800 meters in height and 30 meters in diameter. Source: NASA/JPL-Caltech/U of Arizona

Based on these continued findings the next Martian mission, the Mars Science Laboratory rover, named Curiosity, will study one particular area of Mars to follow the water in pursuit of finding life. Curiosity is scheduled to land on the planet on August 6, 2012. We’ll look at its mission in a future blog.

 
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Space and Humanity in the 21st Century – Part 2: Orbiters, Rovers and Landers on Mars

Published on May 4, 2012 by in 21st century technology, Robots, Space

The state of our exploration of Mars can be described as follows:

  1. We are still wrestling with the results of experiments done by the two Viking landers that visited Mars in 1976.
  2. We are fascinated by the numerous detailed images our robotic orbiters have taken of the planet’s surface.  We see familiar things in land patterns that suggest the presence of water recently and in the past.
  3. We are measuring atmospheric seasonal changes that suggest either a chemical or biological change is occurring impacting the composition of the air from winter to summer and back again.

In the second decade of the 21st century Mars is more a puzzle than understood. The question our Martian adventure is getting close to answering is this: Is Earth the sole planet where living things exist? And we are getting closer to this answer without ever setting a human foot on the planet’s surface. Instead our Martian studies have involved a series of robotic missions loaded with scientific instruments. These missions have included orbiters, robotic landers and rovers. The information we have gleaned from these incredible machines has painted a picture of Mars that is altering our perspective of what constitutes a planet capable of harboring life. Let’s look at some of the technology that has gotten us to this point.

From Odyssey to Spirit and Opportunity

Odyssey

Aptly named Mars Odyssey after Arthur C. Clarke’s novel, 2001: A Space Odyssey, NASA launched this robotic mission to the planet in April 2001. Its primary mission focused on studying the Martian atmosphere, surface and subsurface using three scientific instrument packages named THEMIS, MARIE and GRS. THEMIS was designed to study active thermal occurrences on the Martian surface in order to detect surface minerals by their spectral fingerprint. MARIE was designed to study the radiation from cosmic rays not only in the vicinity and surface of the planet but throughout the interplanetary space between Earth and Mars. GRS was designed to study Martian chemistry using gamma ray and neutron detectors. Odyssey arrived at Mars in October 2001 and entered orbit on the 24th. Its original mission was designed to end in August 2004. The spacecraft continues to operate on an extended mission more than a decade after its arrival.

The Odyssey mission has given us a better picture of both the planet and what a human mission would experience in travelling there. The results of MARIE sampling indicates that humans travelling between Earth and Mars would experience twice as much exposure to cosmic rays as humans on the International Space Station.

This image is compiled from a series of photographs taken by Mars Odyssey on March 13, 2006, combined with LIDAR laser altimetry readings made by the Mars Global Surveyor when it was in orbit. This is a view of the Valles Marineris, a canyon that spans 160 kilometers in width. The THEMIS team at Arizona State University have created a video fly through from which this image is taken. Source: NASA/JPL/Arizona State University

We also have learned from THEMIS that Mars polar ice caps unleash gas jets of CO2 every spring, that the Martian surface has extensive chloride salt deposits left behind when large bodies of liquid water evaporated, that the atmosphere can churn up dust storms and dust devils similar to those found in deserts on Earth, that at least one large crater, Aram Chaos, was once a lake, and that the planet has extensive water-eroded channels on its surface. From GRS data we have detected evidence of substantial subsurface ice as well as deposits of iron, silicon and potassium.

Spirit and Opportunity

In 2004 two robotic spacecraft arrived on the surface of Mars to deploy two rovers, Spirit and Opportunity.  The mission for both rovers packed with scientific instruments was to last 90 days with the objective to explore the Martian terrain, study its geology, look for evidence of water in the past and present and relay images back to Earth receiving stations. Solar power and batteries have provided the power to all the instrumentation and cameras.

Deployed at landing sites on opposite sides of the planet both rovers exceeded expectations with Spirit the first to succumb to the harsh Martian environment as it became trapped in soft Martian terrain in spring of 2009, eventually falling silent during the winter of 2010.

Opportunity, however, continues to chug along as of May 2012, a remarkable feat of technological engineering supported by a dedicated team of Earth based scientists who continue to devise new experiments and missions for the rover.

This mosaic of images taken by Opportunity in January 2012 shows that despite the thinness of its atmosphere, Mars experiences winds that are the active shaper of its landscape today. Source: NASA/JPL-Caltech/Cornell/Arizona State University

What both Spirit and Opportunity discovered shortly after landing included significant evidence that Mars was once a wet environment and that the evidence in the rocks shows that the planet has experienced wet and dry periods throughout its geological history.  While on the Martian surface Opportunity has far outpaced its sister rover, Spirit (7.7 kilometers or 4.8 miles before getting stuck) accumulating a total driving distance of 34.4 kilometers (21.4 miles). To experience a portion of Opportunity’s remarkable journey access the video created by the science support team’s piecing together of end-of-day images taken by the rover as it travelled almost 21 kilometers (13 miles) between the Victoria and Endeavour Craters on the planet’s surface.

Opportunity’s current location is on the edge of Endeavour Crater assignment where it is hunkered down in its fifth Martian winter. Acting as a stationary observation platform it is conducting a study of the interior of the planet using radio-tracking to measure any wobbles as the planet rotates. A significant wobble will indicate whether Mars has a molten core or not. As Martian spring and summer unfold Opportunity will resume its trek, an amazing accomplishment.

The story of our exploration of Mars will continue in our next Space and Humanity in the 21st Century blog.

 

 

 
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