Posted on by Fraser Cain

SOHO Nears 1,000th Comet Discovery

Artist illustration of a comet breaking up as it passes by the Sun. Image credit: NASA. Click to enlarge.
The Solar and Heliospheric Observatory (SOHO) spacecraft is expected to discover its 1,000TH comet this summer. The SOHO spacecraft is a joint effort between NASA and the European Space Agency. It has accounted for approximately one-half of all comet discoveries with computed orbits in the history of astronomy.

“Before SOHO was launched, 16 sungrazing comets had been discovered by space observatories. Based on that experience, who could have predicted that SOHO would discover more than sixty times that number, and in only nine years? This is truly a remarkable achievement!” said Dr. Chris St. Cyr, Senior Project Scientist for NASA’s Living With a Star program at NASA Goddard Space Flight Center in Greenbelt, Md.

Comets are chunks of ice and dust that zoom around the solar system in elongated orbits. This “dirty snowball” is the nucleus of the comet. Comet nuclei are thought to be cosmic leftovers, condensed remains of the gas and dust cloud that formed the solar system.

As a comet gets close to the Sun, solar heat liberates gas and dust from the nucleus, forming the coma, which is an extensive, bright cloud around the nucleus, and one or more tails. A comet’s dust tail can become millions of miles (kilometers) long as sunlight pushes the dust particles away from the Sun. Comets also have a tail of electrically charged particles (ions) that is usually fainter and is pushed away from the Sun by the solar wind, a thin stream of electrified gas that blows constantly from the Sun.

About 85 percent of the SOHO comets discovered so far belong to the Kreutz group of “sungrazing” comets, so named because their orbits take them very close to the Sun. The Kreutz sungrazers come within 500,000 miles (800,000 km) of the Sun’s visible surface. (Mercury, the planet closest to the Sun, is about 36 million miles (57.6 million km) from the solar surface.) SOHO has also been used to discover three other well-populated comet groups: the Meyer (at least 55 members), Marsden (at least 21 members), and Kracht (24 members) groups. These comet groups are named after the astronomers who suggested that the comets are related because they have similar orbits.

Because comets in a group have similar orbits, they are believed to be fragments from a larger comet that broke apart. Sungrazing comets can break up as they approach the Sun due to the Sun’s gravity and heat. It is likely that small fragments continue to break off all around their orbits, because SOHO observes a stream with tiny Kreutz members reaching the Sun almost every day, and bits as small as these would have simply vaporized if this had happened near the Sun. Most of these comet fragments are not visible from Earth because their small size makes them extremely faint. A typical comet nucleus is as big as a mountain, while most of the SOHO comets are only as big as a large room or small house.

However, since the Kreutz group is so numerous, the parent comet that shattered to create Kreutz comets is estimated to have been truly immense, about 60 miles (100 km) across. The great comets of 1843 and 1882, with long tails that were spectacular to the naked eye were large Kreutz members, as was comet Ikeya-Seki in 1965. The 1882 and 1965 comets almost certainly broke off from each other the previous time they were near the Sun, when the combined comet was likely seen as the comet of 1106.

Many SOHO comet discoveries have been by amateurs using SOHO images on the internet. SOHO comet hunters come from all over the world; the United States, United Kingdom, China, Japan, Taiwan, Russia, Ukraine, France, Germany, and Lithuania are among the many countries whose citizens have used SOHO to chase comets.

Almost all SOHO’s comets are discovered using images from its Large Angle and Spectrometric Coronagraph (LASCO) instrument. LASCO is used to observe the faint, multimillion-degree outer atmosphere of the Sun, called the corona. A disk in the instrument is used to make an artificial eclipse, blocking direct light from the Sun so the much fainter corona can be seen. Sungrazing comets are discovered when they enter LASCO’s field of view as they pass close by the Sun. “Building coronagraphs like LASCO is still more art than science, because the light we are trying to detect is very faint,” said Dr. Joe Gurman, U.S. Project Scientist for SOHO at NASA Goddard. “Any imperfections in the optics or dust in the instrument will scatter the light, making the images too noisy to be useful. Discovering almost 1,000 comets since SOHO’s launch on December 2, 1995 is a testament to the skill of the LASCO team.”

SOHO successfully completed its primary mission in April 1998, and it has enough fuel to remain on station and keep hunting comets for decades, assuming the LASCO instrument continues to function. Additionally, NASA’s twin Solar Terrestrial Relations Observatory (STEREO) spacecraft, scheduled for launch in February 2006, each have two instruments that could be used to discover comets: a coronagraph like LASCO and a heliospheric imager.

Original Source: NASA News Release

Posted on by Fraser Cain

Artificial Meat Could Be Grown on a Large Scale

A magnified view of muscle fibres. Image credit: UM. Click to enlarge.
Experiments for NASA space missions have shown that small amounts of edible meat can be created in a lab. But the technology that could grow chicken nuggets without the chicken, on a large scale, may not be just a science fiction fantasy.

In a paper in the June 29 issue of Tissue Engineering, a team of scientists, including University of Maryland doctoral student Jason Matheny, propose two new techniques of tissue engineering that may one day lead to affordable production of in vitro – lab grown — meat for human consumption. It is the first peer-reviewed discussion of the prospects for industrial production of cultured meat.

“There would be a lot of benefits from cultured meat,” says Matheny, who studies agricultural economics and public health. “For one thing, you could control the nutrients. For example, most meats are high in the fatty acid Omega 6, which can cause high cholesterol and other health problems. With in vitro meat, you could replace that with Omega 3, which is a healthy fat.

“Cultured meat could also reduce the pollution that results from raising livestock, and you wouldn’t need the drugs that are used on animals raised for meat.”

Prime Without the Rib
The idea of culturing meat is to create an edible product that tastes like cuts of beef, poultry, pork, lamb or fish and has the nutrients and texture of meat.

Scientists know that a single muscle cell from a cow or chicken can be isolated and divided into thousands of new muscle cells. Experiments with fish tissue have created small amounts of in vitro meat in NASA experiments researching potential food products for long-term space travel, where storage is a problem.

“But that was a single experiment and was geared toward a special situation – space travel,” says Matheny. “We need a different approach for large scale production.”

Matheny’s team developed ideas for two techniques that have potential for large scale meat production. One is to grow the cells in large flat sheets on thin membranes. The sheets of meat would be grown and stretched, then removed from the membranes and stacked on top of one another to increase thickness.

The other method would be to grow the muscle cells on small three-dimensional beads that stretch with small changes in temperature. The mature cells could then be harvested and turned into a processed meat, like nuggets or hamburgers.

Treadmill Meat
To grow meat on a large scale, cells from several different kinds of tissue, including muscle and fat, would be needed to give the meat the texture to appeal to the human palate.

“The challenge is getting the texture right,” says Matheny. “We have to figure out how to ‘exercise’ the muscle cells. For the right texture, you have to stretch the tissue, like a live animal would.”

Where’s the Beef?
And, the authors agree, it might take work to convince consumers to eat cultured muscle meat, a product not yet associated with being produced artificially.

“On the other hand, cultured meat could appeal to people concerned about food safety, the environment, and animal welfare, and people who want to tailor food to their individual tastes,” says Matheny. The paper even suggests that meat makers may one day sit next to bread makers on the kitchen counter.

“The benefits could be enormous,” Matheny says. “The demand for meat is increasing world wide — China ‘s meat demand is doubling every ten years. Poultry consumption in India has doubled in the last five years.

“With a single cell, you could theoretically produce the world’s annual meat supply. And you could do it in a way that’s better for the environment and human health. In the long term, this is a very feasible idea.”

Matheny saw so many advantages in the idea that he joined several other scientists in starting a nonprofit, New Harvest, to advance the technology. One of these scientists, Henk Haagsman, Professor of Meat Science at Utrecht University, received a grant from the Dutch government to produce cultured meat, as part of a national initiative to reduce the environmental impact of food production.

Other authors of the paper are Pieter Edelman of Wageningen University , Netherlands ; Douglas McFarland, South Dakota State University ; and Vladimir Mironov, Medical University of South Carolina.

Original Source: UM News Release

Posted on by Fraser Cain

Podcast: Summer at the Lake… on Titan

Ah, summer. Long relaxing days spent at the lake, just swimming, fishing, and enjoying the scenery. Think you can only enjoy lakes here on Earth? Well, think again. NASA’s Cassini spacecraft might have turned up a lake on Titan, Saturn’s largest moon. It might not be the kind of lake you’re used to though. The average temperature on Titan is only a hundred degrees above Absolute Zero, so it’s probably a lake of liquid hydrocarbons. Carolyn Porco is the leader on the imaging team on the Cassini mission to Saturn and the director for the Center of Imaging Operations at the Space Science Institute in Boulder, Colorado. That’s where the images from Cassini are processed and released to the public.
Continue reading “Podcast: Summer at the Lake… on Titan”

Posted on by Fraser Cain

Audio: Summer at the Lake… on Titan

Possible lake on Titan. Image credit: NASA/JPL/SSI. Click to enlarge.
Listen to the interview: Summer at the Lake… on Titan (6 MB)

Or subscribe to the Podcast: universetoday.com/audio.xml

Fraser Cain: Let’s say I’m standing on the surface of Titan beside this feature, what would I be seeing?

Carolyn Porco: Well, we’re not absolutely sure, but if it is, in fact, a lake of hydrocarbons, then you would see something that would look rather dark. It may have some materials disolved in it and perhaps waves would be lapping up at the shore which would of course be ice, water ice. Mind you, it’s incredibly cold. Overall, the scene would be very dark because high noon on Titan is like deep Earth twilight, and it might even be possibly raining methane because this feature has been found in the place on Titan where there seems to be the most clouds and therefore the greatest likelihood of rain. Not that Titan is a very cloudy place, mind you. We haven’t seen many clouds on Titan. Where we’ve seen clouds is mostly in the south polar region where this feature the size of Lake Ontario has been found.

Fraser: Now I know that images of Titan taken by Voyager and other telescopes show it as a very smoggy, cloudy world. So, how can we see the lake?

Porco: There’s a difference between smog, haze and then clouds. Clouds are particulates of some condensable material; it could be liquid droplets or the fact is if they’re high enough they could be solid particles. On the Earth, cirrus clouds are made of water ice, unlike your normal cumulous clouds that rain on you; they rain liquid water. So we could have a similar thing going on Titan, except the material, of course, is methane. But as I said, there aren’t many clouds. It’s not clouds which are making the surface of Titan so difficult to see from high above. It’s haze particles – these are haze particles, like smog particles on Earth – probably made, almost certainly made, of hydrocarbon materials, polymers probably, of carbons all linked together. These are very small particles, but the atmosphere is very very thick; hundreds of kilometres thick with this stuff. If you’re standing on the surface, you can, of course, see the surface and see even to the horizon, and a bit through it. Mind you, recall what the images taken by the Huygens probe looked like. We could see to the horizon, once the probe was on the surface and took pictures, we could see to the horizon. But if you look up through the very thick atmosphere, or if you’re above looking down, then your path through this thick atmosphere filled with haze is so long, that it’s difficult for visible light to get through. And of course, we see with visible light. In images taken with Voyager, and Voyager had a camera that could look only to the long end of where humans see with their eyes; in fact, a little beyond where we see with our eyes. But nonetheless, not far enough to see down to the surface of Titan. But with the Cassini cameras, we have used a trick that was discovered basically by ground-based astronomers. If you go to the longer wavelengths in the electromagnetic spectrum, you go into the near-infrared, you can in fact see down to the surface of Titan. Those are the wavelengths that we have used to image the surface of Titan with our cameras, and of course, it is in those wavelengths that we discovered this lakelike feature on the surface.

Fraser: Now, if it isn’t a lake of liquid hydrocarbon, what else could it be?

Porco: Well, we’re not completely sure, 100% sure, that it’s filled with liquid. Perhaps it was a depression that once was filled with liquid, and all the liquid has since evaporated, and we’re now seeing the residue of what was left behind. So it could be solid hydrocarbons that still would form a flat surface. You could imagine a salt lake bed on the Earth; the salt having been left behind after the water evaporated. So we could be seeing something that is just solid material. That’s the two basic possiblities: it could be solid material or it could be liquid. We won’t know for sure whether or not it’s liquid until we have the opportunity to see a reflection of the Sun in the surface of this body; a specular reflection, or mirror like reflection like you can see if you’re flying in an airplane over Minnesota for example. Looking down on the ground and it’s daylight, you can see specular reflections; you can see the image of the Sun glinting off the surface of all the many lakes that dot the landscape of Minnesota.

Fraser: That’s incredible, you’ll be able to see that?

Porco: We won’t be able to see that with our cameras, probably, because the geometry won’t allow us to. The solar illumination geometry and the fact that, at the wavelengths that even the Cassini cameras can see, if we look through too long a path length in the atmosphere, things get very hazy and fuzzy, and we don’t get a clear view of the surface. However, there are other instruments on Cassini that work at longer wavelengths than we do, and they go further into the near infrared. They have an easier time seeing down to the surface, and it’s possible – we have to check the upcoming encounters with Titan. So this is not a certainty yet, but at least in principle it’s possible that they could see a mirror like reflection off the surface of this body, if in fact it’s liquid. The jury is still out on this, and we may be lucky to have the kind of circumstances on future flybys of Titan to catch whether or not it’s truly liquid.

Fraser: When will Cassini have a chance to revisit the area?

Porco: I’m not quite certain of that. There are people on my team who are busy planning the Titan flybys; planning the imaging sequences for each of the upcoming Titan flybys would know that better than I do. But I think it may not be until later on in the tour when we really have a good look again at this feature. As I’ve said many times, it’s going to take us years to work out what’s truly going on on the surface of Titan. We come by it many times during the course of this mission, which ends nominally in the middle of 2008. If we’re lucky enough, and the American Congress is willing, we’ll get an extension, and we could be observing bodies in the Saturn system for the next decade. But right now we have something like 39 further encounters with Titan.

Fraser: And if it does turn out to be liquid hydrocarbon, what does that tell you about Titan’s geology or its history?

Porco: It tells that at least in part, the thinking that we had about the methane cycle on Titan, and the amount of methane in the atmosphere is correct. Because there had been predictions that the surface of Titan would have some liquids on the surface. And we haven’t seen as many as some of the models had predicted, but if there is any at all, that gives a source of the methane that’s in the atmosphere, if there’s some liquid on the surface. Of course, the next question is: how did that amount of methane get into the atmosphere to begin with? Did it come from volcanoes, or did it come from some other source? The question of how methane can even exist right now on the surface of Titan, when we know it’s being broken up in the upper atmosphere. But still, it confirms for us, at least in part, some of our thinking about what is going on between the surface and the atmosphere, and that’s interesting to know. This is another atmosphere, in many ways similar to our Earth. It gives us another example to study in learning about our own atmosphere. Bear in mind that Titan also has a kind of mild greenhouse effect going on. It’s surface temperature is 12-degrees Kelvin greater than it would be otherwise, if there were no methane in its atmosphere. So, we stand to learn a lot about our own planet, and what makes our own planet unique, and what makes it have anything in common at all with some other body, like Titan, by studying Saturn’s largest moon.

Fraser: Have you imaged Titan well enough now to know that this is the only feature like this on the planet?

Porco: Oh, not by a long shot. We’re just beginning here. These are early days. I don’t know what percentage of the surface has been covered yet, but it’s still a small fraction at the kind of resolution that we would need to see these kinds of features. So no, we have a long way to go, and I think there’s going to be a lot more exciting discoveries in store, so stay tuned is the message really.

Visit the CICLOPS website.

Posted on by Fraser Cain

Deep Impact Made a Bright Flash

The brilliant flash of light created by Deep Impact as it smashed into Tempel 1. Image credit: NASA/JPL. Click to enlarge.
The hyper-speed demise of NASA’s Deep Impact probe generated an immense flash of light, which provided an excellent light source for the two cameras on the Deep Impact mothership. Deep Impact scientists theorize the 820-pound impactor vaporized deep below the comet’s surface when the two collided at 1:52 am July 4, at a speed of about 10 kilometers per second (6.3 miles per second or 23,000 miles per hour).

“You can not help but get a big flash when objects meet at 23,000 miles per hour,” said Deep Impact co-investigator Dr. Pete Schultz of Brown University, Providence, R.I. “The heat produced by impact was at least several thousand degrees Kelvin and at that extreme temperature just about any material begins to glow. Essentially, we generated our own incandescent photo flash for less than a second.”

“They say a picture can speak a thousand words,” said Deep Impact Project Manager Rick Grammier of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “But when you take a look at some of the ones we captured in the early morning hours of July 4, 2005 I think you can write a whole encyclopedia.”

At a news conference held later on July 4, Deep Impact team members displayed a movie depicting the final moments of the impactor’s life. The final image from the impactor was transmitted from the short-lived probe three seconds before it met its fiery end.

“The final image was taken from a distance of about 30 kilometers (18.6 miles) from the comet’s surface,” said Deep Impact Principal Investigator Dr. Michael A’Hearn of the University of Maryland, College Park. “From that close distance we can resolve features on the surface that are less than 4 meters (about 13 feet) across. When I signed on for this mission I wanted to get a close-up look at a comet, but this is ridiculous? in a great way.”

The Deep Impact scientists are not the only ones taking a close look at their collected data. The mission’s flight controller team is analyzing the impactor’s final hours of flight. When the real-time telemetry came in after the impactor’s first rocket firing, it showed the impactor moving away from the comet’s path.

“It is fair to say we were monitoring the flight path of the impactor pretty closely,” said Deep Impact navigator Shyam Bhaskaran of JPL. “Due to the flight software program, this initial maneuver moved us seven kilometers off course. This was not unexpected but at the same time not something we hoped to see. But then the second and third maneuvers put us right where we wanted to be.”

The Deep Impact mission was implemented to provide a glimpse beneath the surface of a comet, where material from the solar system’s formation remains relatively unchanged. Mission scientists hoped the project would answer basic questions about how the solar system formed, by providing an in-depth picture of the nature and composition of the frozen celestial travelers known as comets. The University of Maryland is responsible for overall Deep Impact mission science, and project management is handled by JPL. The spacecraft was built for NASA by Ball Aerospace & Technologies Corporation, Boulder, Colo.

For information about Deep Impact on the Internet, visit http://www.nasa.gov/deepimpact.

Original Source: NASA News Release

Posted on by Mark Mortimer

Book Review: Big Bang: The Origin of the Universe

I’ll declare this right from the start, Simon Singh is one of my favorite science writers. His two previous books, Fermat’s Enigma and The Code Book are excellent. Especially the Code Book, which I was a little nervous to read, but walked away with a very firm understanding of codes and codebreaking through the centuries.

With Big Bang, Singh starts right at the beginning of cosmology, as the ancient Greeks showed a surprising series of leaps of logic about the Solar System. They correctly understood that the Earth is a sphere, and estimated its size. They calculated the distance to the Moon, and even took a stab at guessing the distance to the Sun. Unfortunately, they developed an incorrect view of an Earth-centred Universe, where the Sun, stars and the planets orbit the Earth. As errors developed in their theory, the Earth-centred astronomers just made their model more complex to compensate.

The book goes on to present discoveries in cosmology, one after the other, from the Copernicus Sun-centred view to Edwin Hubble’s discovery that many distant “nebulae” are actually other galaxies, like our Milky Way. Hubble then went on to discover that these distant galaxies are actually speeding away from us. It’s this discovery, that our Universe is expanding, which led to the theory we now call the Big Bang.

The Big Bang is such a profound theory, and it’s even more amazing because it’s embraced by nearly everyone working in cosmology today. Thank the evidence for this. Singh tracks down each piece of evidence supporting the Big Bang: the abundance of hydrogen in the Universe, the discovery that galaxies are speeding away from us, and the cosmic microwave background radiation. He introduces the reader to the cast of characters involved in each discovery, and then leads us through the observations and breakthroughs that formed this piece of evidence. We also meet the challengers and understand their differing, and very valid, viewpoints.

While reading Big Bang, you get the sense the Singh wanted to get across how well supported a theory the Big Bang is. This isn’t some half-baked theory about the Universe; the cosmologists who developed the Big Bang made some dramatic predictions which have turned out to be supported by observation. Some of the most dramatic are the most recent, with the Wilkinson Microwave Anisotropy Probe, which mapped variations in the microwave background radiation with such exquisite detail to help explain variations of matter in the Universe – why there are clumps of matter, like galaxies, planets, and people, and not just a rapidly spreading mist of equally-spaced hydrogen.

As I was reading Big Bang, through, I kept noticing how quickly I was moving through the book, and how slowly the story was progressing. Not that I was bored, but I was amazed at how long it took for discoveries to be presented. Once there was only a sliver remaining, I realized that I had slightly misjudged what the book was going to be about. Singh essentially wraps up with the discovery of the cosmic microwave background radiation by Penzias and Wilson – case closed, that’s the story of the Big Bang.

I follow astronomy and cosmology on a daily basis, and I know the story isn’t over. There are many intriguing discoveries being made all the time, such as dark energy, dark matter, and inflationary cosmology. Singh gives each of these subjects little more than a sentence or two in an epilogue, and this is unfortunate. I would have liked to see him tackle these fascinating subjects with the same care and skill that he handled the rest of the book. Perhaps a sequel Simon?

If you’re interested in astronomy, and want to get a nice overview of the Big Bang, I highly recommend this book by Simon Singh. It’s easy to read and understand, and gives a great overview of the theory, the theorists, and the evidence.

Read more reviews or order a copy online from Amazon.com

Review by Fraser Cain

Posted on by Fraser Cain

Deep Impact Smashes Into Tempel 1

View of the material ejected from Tempel 1. Image credit: NASA/JPL.
After 172 days and 431 million kilometers (268 million miles) of deep space stalking, Deep Impact successfully reached out and touched comet Tempel 1. The collision between the coffee table-sized impactor and city-sized comet occurred at 1:52 a.m. EDT.

“What a way to kick off America’s Independence Day,” said Deep Impact Project Manager Rick Grammier of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “The challenges of this mission and teamwork that went into making it a success, should make all of us very proud.”

“This mission is truly a smashing success,” said Andy Dantzler, director of NASA’s Solar System Division. “Tomorrow and in the days ahead we will know a lot more about the origins of our solar system.”

Official word of the impact came 5 minutes after impact. At 1:57 a.m. EDT, an image from the spacecraft’s medium resolution camera downlinked to the computer screens of the mission’s science team showed the tell-tale signs of a high-speed impact.

“The image clearly shows a spectacular impact,” said Deep Impact principal investigator Dr. Michael A’Hearn of the University of Maryland, College Park. “With this much data we have a long night ahead of us, but that is what we were hoping for. There is so much here it is difficult to know where to begin.”

The celestial collision and ensuing data collection by the nearby Deep Impact mothership was the climax of a very active 24 hour period for the mission which began with impactor release at 2:07 a.m. EDT on July 3. Deep space maneuvers by the flyby, final checkout of both spacecraft and comet imaging took up most of the next 22 hours. Then, the impactor got down to its last two hours of life.

“The impactor kicked into its autonomous navigation mode right on time,” said Deep Impact navigator Shyam Bhaskaran, of JPL. “Our preliminary analysis indicates the three impactor targeting maneuvers occurred on time at 90, 35 and 12.5 minutes before impact.”

At the moment the impactor was vaporizing itself in its 10 kilometers per second (6.3 miles per second) collision with comet Tempel 1, the Deep Impact flyby spacecraft was monitoring events from nearby. For the following14 minutes the flyby collected and downlinked data as the comet loomed ever closer. Then, as expected at 2:05 a.m. EDT, the flyby stopped collecting data and entered a defensive posture called shield mode where its dust shields protect the spacecraft’s vital components during its closest passage through the comet’s inner coma. Shield mode ended at 2:32 a.m. EDT when mission control re-established the link with the flyby spacecraft.

“The flyby surviving closest approach and shield mode has put the cap on an outstanding day,” said Grammier. “Soon, we will begin the process of downlinking all the encounter information in one batch and hand it to the science team.”

The goal of the Deep Impact mission is to provide a glimpse beneath the surface of a comet, where material from the solar system’s formation remains relatively unchanged. Mission scientists expect the project will answer basic questions about the formation of the solar system, by offering a better look at the nature and composition of the frozen celestial travelers known as comets.

The University of Maryland is responsible for overall Deep Impact mission science, and project management is handled by JPL. The spacecraft was built for NASA by Ball Aerospace & Technologies Corporation, Boulder, Colo.

For information about Deep Impact on the Internet, visit http://www.nasa.gov/deepimpact.

Original Source: NASA/JPL News Release

Posted on by Mark Mortimer

Book Review: Conflict in the Cosmos, Fred Hoyle’s Life in Science

Fred Hoyle climbed through the challenges of Britain during the inter-war years. His diligence to his primary schooling was poor to say the least. Playing hookey was the order of his day. However, fortune smiled on him. Through this and his own effort, he managed to achieve a number of scholarships that kept him advancing until he gained acceptance into Cambridge University. There followed a checkered career as he studied mathematics with special application to nuclear physics. He had a short diversion due to the second world war where he advanced the state of electronic warfare. After, he jumped into the field of astronomy with both feet. During the remainder of his life, Fred Hoyle advanced this field and contributed to many others, often as not, by leading the explorations.

Leading any field is a balancing act between divining the future and keeping up with current events. Here emotion comes to the fore and here is where Mitton concentrates his book. He shows how Fred Hoyle, being in theoretical astronomy, often came to grips with observational astronomers. Further, Mitton builds a feeling that Fred Hoyle was like a kettle constantly steaming. Continual requests for publication were countered by people not understanding, or believing or wanting his views presented. Apparently, during most of his career, Fred Hoyle was at odds with the Royal Astronomical Society even though he was a member for most of his life. As well, Mitton shows how he appears to have used the largess of Cambridge to pursue his own work. In particular, he was a mentor who was seldom present. When he was, he was so caught up in his own theories, he didn’t always give the attention graduate students deserved. The resulting picture is of a vibrant, thoughtful, and analytical mathematician at the top of his game.

Mitton’s biography includes a mix of both personal and technical aspects to Fred Hoyle’s life. We read of Friday lunches in dimly lit rooms little better than cloisters. Further along there are recounts to a remarkable passion for hiking. He achieved the Munro, a climbing of a collection of hills in Scotland over 914 metres. He drove fast cars, enjoyed conferences by the lakes in Northern Italy and championed a telescope in Australia. Mitton relies on Fred Hoyle’s own autobiography as well as many friends and acquaintances to ensure accuracy and detail in the recollections.

On the technical side, Mitton details contribution to radar such as the bending of beams along the curvature of the Earth. Nucleosynthesis, one of the main focuses of Fred Hoyle’s career, gets a detailed and historical recount. Added are accounts of collaborations with experts as well as competitions against others. Mitton presents the information in a smooth, qualitative manner so there is no worry of confusion. All in all, Mitton builds an excellent link between the people, their discoveries and knowledge of the day that is both enjoyable to read and enlightening in its own way.

The interesting mix of personalities and technical information works well. Chapters are loosely divided chronologically. However, as Fred Hoyle had his finger into so many pies, Mitton decided to collect information into subject areas and deal with them chronologically. Due to this, there is a fair amount of jumping around in time throughout the text. This isn’t unduly bothersome but the reader must stay aware. Given the details on radar, advanced cosmology, science fiction novels, movie scripting, and leading an international collaboration on siting and building an observatory, this book is more of an insight into Fred Hoyle’s technical contributions than his personality.

Fred Hoyle’s emotions drove him to advance our understanding of cosmology. His work as a theoretical astronomer and science communicator captured the imaginations of people. Simon Mitton in his biography Conflict in the Cosmos, Fred Hoyle’s Life in Science brings back the life of Fred Hoyle, including the people and some of the technical issues of a person at the top of their game. Emotions are free to everyone, perhaps reading this will entice you on your own search for understanding.

Read more reviews, or order copy online from Amazon.com.

Review by Mark Mortimer

Posted on by Fraser Cain

Largest Core in an Extrasolar Planet

Artist illustration of the planet orbiting the sun-like star HD 149026. Image credit: U.C. Santa Cruz. Click to enlarge.
NASA researchers recently discovered the largest solid core ever found in an extrasolar planet, and their discovery confirms a planet formation theory.

“For theorists, the discovery of a planet with such a large core is as important as the discovery of the first extrasolar planet around the star 51 Pegasi in 1995,” said Shigeru Ida, theorist from the Tokyo Institute of Technology, Japan.

When a consortium of American, Japanese and Chilean astronomers first looked at this planet, they expected one similar to Jupiter. “None of our models predicted that nature could make a planet like the one we are studying,” said Bun’ei Sato, consortium member and postdoctoral fellow at Okayama Astrophysical Observatory, Japan.

Scientists have rarely had opportunities like this to collect such solid evidence about planet formation. More than 150 extrasolar planets have been discovered by observing changes in the speed of a star, as it moves toward and away from Earth. The changes in speed are caused by the gravitational pull of planets.

This planet also passes in front of its star and dims the starlight. “When that happens, we are able to calculate the physical size of the planet, whether it has a solid core, and even what its atmosphere is like,” said Debra Fischer. She is consortium team leader and professor of astronomy at San Francisco State University, Calif.

The planet, orbiting the sun-like star HD 149026, is roughly equal in mass to Saturn, but it is significantly smaller in diameter. It takes just 2.87 days to circle its star, and the upper atmosphere temperature is approximately 2,000 degrees Fahrenheit. Modeling of the planet’s structure shows it has a solid core approximately 70 times Earth’s mass.

This is the first observational evidence that proves the “core accretion” theory about how planets are formed. Scientists have two competing but viable theories about planet formation.

In the “gravitational instability” theory, planets form during a rapid collapse of a dense cloud. With the “core accretion” theory, planets start as small rock-ice cores that grow as they gravitationally acquire additional mass. Scientists believe the large, rocky core of this planet could not have formed by cloud collapse. They think it must have grown a core first, and then acquired gas.

“This is a confirmation of the core accretion theory for planet formation and evidence that planets of this kind should exist in abundance,” said Greg Henry, an astronomer at Tennessee State University, Nashville. He detected the dimming of the star by the planet with his robotic telescopes at Fairborn Observatory in Mount Hopkins, Arizona.

Original Source: NASA News Release