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‘Survival’ is the fourth installment in a series of novels from six-time nebula award winning author Ben Bova. The series began with ‘New Earth’ where a human starship encounters a machine intelligence that calls itself ‘The Predecessors’. The machines inform the human crew that a ‘Death Wave’ of gamma radiation is spreading out from the supermassive black hole at the center of the galaxy that will destroy all life on the planets in our galactic neighborhood.

Front Cover of ‘Survival’ by Ben Bova (Credit: Amazon) Six time Nebula award winning author Ben Bova (Credit: From his Facebook page)

The Predecessors want to make a deal with humanity. They will give us the technology to survive the death wave if we agree to spread that technology to other intelligent species that are also threatened. In the second novel ‘Death Wave’ the crew returns to Earth and succeeds in convincing humanity to undertake this task, see my post of 31 May 2017.

The Death Wave series prior to ‘Survival’ (Credit: Ben Bova.com)

The third novel ‘Apes and Angels’, see my post of 31Mar 2018, tells the story of one such expedition to save an intelligent, albeit primitive alien lifeform. In the latest installment ‘Survival’ the crew of the starship Intrepid undertake a 2,000 year long journey, the crew is in suspended animation, to a star system inhabited by another machine intelligence.

If you think about it, with this Death Wave idea Ben Bova has created for himself a fictional Universe that can support any number of novels. A human starship travels to a distant star, has whatever adventure Bova has thought of and so long as he can loosely connect it to the Death Wave concept it fits into the series.

The main plot in ‘Survival’ concerns the way the machines treat their human visitors. They don’t need the human’s help in surviving the Death Wave and the machines don’t really trust organic life to begin with. “Organic life is ephemeral,” the crew of the Intrepid is told several times, “Only machines are immortal.”

There are a couple of subplots in ‘Survival’ as well, one being the way that successful scientists often wind up becoming administrators who no longer have the time to do any research. The second is buried kind of deep but you catch it by the end, it’s the simple question of which is the better survival strategy, competition or cooperation?

If all of these concepts sound familiar to you maybe it’s because they’ve been storylines in science fiction for decades now, the old Star Trek TV shows did versions of all of them.

The Star Trek episode ‘Return of the Archons’ was just one of several to depict a conflict between man and machine (Credit: Desilu Studios)

Indeed ‘Survival’ does have a Star Trek sort of feel about it, although without any of the action sequences. In fact there is little of anything that could be called action in ‘Survival’ and maybe that’s a good thing. Right now it seems as if SF novels are just full of violence, the last four novels I’ve reviewed all have a significant amount of murder and mayhem in them. (See my posts of 25Nov2018, Freefall; 12Dec2018 Planetfall; 13Feb2019, One Way and 3Apr2019, The Children of Time)

So an SF novel that succeeds, that makes you think without anybody getting killed is a nice breath of fresh air. It’s easy to use SF as just an excuse for a variant on a cowboy story with ray guns in place of six shooters and starships in place of wagon trains but the best Science Fiction is about thinking, not shooting!

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Most people know that the dinosaurs dominated Earth for over 150 million years but of course it wasn’t just one species of dinosaur and not all of the dinosaurs were so dominating. Some species were smaller, more inconspicuous relatives of the better-known giants while others represented evolutionary experiments that, for one reason or another simply did not leave any descendents, in other words they were experiments that failed.

I’ll start with the recent discovery of a relative of the famous Tyrannosaurus rex discovered in New Mexico by Dr. Sterling Nesbitt of Virginia Tech College of Science’s Department of Geosciences. Named Suskityrannus hazelae the two-legged theropod likely measured about 2.7 m from the tip of its nose to the end of its tail and stood less than a meter tall at the hip. This small meat eating would have weighted between 20 and 40 kg and likely hunted smaller animals.

An Artist’s illustration of Suskityrannus hazelae (Credit: Andrey Atuchin)

According to Dr. Nesbitt, “Suskityrannus hazelae gives us a glimpse into the evolution of tyrannosaurs just before they take over the planet.” Based on the geologic strata in which it was discovered S hazelae lived some 92 million years ago near the beginning of the Cretaceous period. Because of the time it lived along with its anatomy S hazelae could prove to be a link between the older and smaller tyrannosauroids of North America and China and the much larger tyrannosaurids of which T rex is the best-known member.

Dr. Sterling Nesbitt with the bones of S hazelae (Credit: Virginia Tech)

The second new species of dinosaur to be discovered is rather a bit stranger. Ambopteryx longibrachium is a species of theropod dinosaur that flew, or perhaps only glided, with leathery bat like wings. Now I’m not talking about one of the pterosaurs, those bat like reptiles that lived at the same time as the dinosaurs but which weren’t dinosaurs.

The flying reptiles known as Pterosaurs were not dinosaurs! Their anatomy is different! (Credit: Iraber.info)

A longibrachium is a theropod, the same group of dinosaurs that includes T-rex and from which the true flying dinosaurs, better known as birds, would come. In fact A longibrachium lived approximately at the same time as the first birds, the late Jurassic period some 163 million years ago, about the same time as the famous Archaeopteryx.

Artist’s illustration of what Ambopteryx Longibrachium may have looked like (Credit: Smithsonian)

The fossils of A longibrachium are remarkably well preserved not only showing the membrane of their leathery wings but also the impressions of fuzzy feathers that were probably helped to keep the animal warm. The most critical part of the anatomy to be preserved was an enlarged, rod like wrist bone known as a styliform, an adaptation previously unknown in dinosaurs but present in pterosaurs and flying squirrels.

The actual fossil of A longibrachium. The leathery wings are quite obvious (Credit: Discovery Magazine)

The fossil remains of A longibrachium were discovered in China by scientists at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences. Over the last few decades there has been a lot of paleontological research underway in China with important discoveries being made in many different periods of Earth’s history. (See my post of 10 April 2019)

Ambopteryx longibrachium fits into the evolutionary tree of small theropods very closely to those who would become the birds! (Credit: Nature)

So what happened to the dinosaurs like A longibrachium? Well perhaps the bat winged dinosaurs lost out to their relatives the evolving true birds. Or perhaps there was some ecological crisis that the bat winged dinosaurs failed to survive. We can’t say at present, but you can be certain that the paleontologists will keep searching for the answers, and isn’t that what science is all about!

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The danger of an asteroid or comet striking the Earth has been used as a plot device in a number of science fiction books and movies over the last century. The threat is real however, objects as large as a house strike the Earth every few decades or so, the Tunguska meteor in 1908 is a well know example, and it is well established that a space rock approximately ten kilometers in diameter triggered the extinction of the dinosaurs.

Tress snapped off at the ground by the Tunguska meteor event in Russia in 1908 (Credit: STSTW)

For the entire history of Earth the living things on this planet were absolutely helpless to protect themselves against this cosmic bombardment but that may be about to change. After all, we humans are space travelers now, so we ought to be able to figure out some ways to defend our planet against a collision with a mountain flying through space.

The first thing we need to do is to get an accurate idea of the scale of the problem. Just how many rocks are out there that can threaten the Earth, and what are their sizes? Such objects are known officially as Near Earth Objects or NEOs and NASA actually has the task of cataloging them well underway.

Over the last decade a team of astronomers manning medium sized telescopes have been searching the skies for every asteroid that comes close to our planet and so far over 20,000 of all sizes have been found, their size estimated and an approximate orbit calculated.

Number of NEOs discovered over the last thirty years (Credit: NASA / JPL)

O’k, so if they find an asteroid coming at us, then what do we do? Hollywood’s favourite solution is to blow the asteroid to bits, which could actually make the problem worse, now you could have a dozen or more asteroids headed towards Earth.

Hollywood’s portrayal of an Asteroid colliding with the Earth (Credit: Tumblr)

Given enough warning before a collision with an NEO, say a decade or more, a small rocket engine could be placed on the asteroid’s surface and used to alter its path so that it misses our planet by a comfortable margin. (Ten centimeters per second is a very slow speed but after ten years it amounts to more than 30,000 km!) If given even more time perhaps just nudging the asteroid by hitting it with an unmanned space probe could accomplish the same thing.

Any of these techniques might work on some asteroids, but not on others. We need to do some testing, and that is just what NASA is planning on doing in October of 2022. The mission is called the Double Asteroid Redirection Test or DART.

The DART Space Craft with its electric Ion rocket engine firing (Credit: Space.com)

The DART probe will be sent to the double asteroid Didymos which consists of two asteroids orbiting one another, didymos is Greek for twin. After a thorough study of the orbital paths of the two asteroids the DART space probe will be commanded to slam into the smaller asteroid at a velocity of nearly 6 kps.

Radar Images of the large Asteroid Didymos and its little moon Didymoon (Credit: NASA) The DART space probe will slam into ‘Didymoon’ on 7 October 2022 (Credit: Daily Express)

By observing both the collision itself and any changes to the orbits of the two asteroids relative to each other the DART mission will provide the first real measurement of the possible changes we may be able to make to an asteroid’s path. The knowledge gained from DART and similar missions will allow NASA to begin to develop practical plans for defending Earth against any threat of an impact from space.

And speaking of NEOs NASA has also announced that on April 13, 2029 the 340 m wide asteroid Apophis will sweep past Earth close enough to be visible with the naked eye. The asteroid will come within 31,000 km of Earth’s surface, closer than our geostationary communications satellites. The video below shows the encounter as it might appear for someone on the Moon, and who knows, by then there may be someone on the Moon.

Astronomers are already planning for the observations they’d like to make and I’m certain that all the World’s space agencies will be thinking about possible missions they could make to Apophis as it flies by. As for me, I intend to see Apophis as it passes Earth but Philadelphia is usually rather cloudy during April. Maybe that’ll be a good excuse to go someplace nice and sunny for a week or so!

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So which did you like better, ‘Avengers, Endgame’ or ‘Game of Thrones, The Long Night’. If you think about it they have a lot in common. Both are the climax of story lines that have been developed over a decade or so. Both have had major subplots. Both have introduced major characters along the way. Both wind up in tremendous battles between the forces of good and evil. I could go on but I’ll just add one more because both include the loss of several characters that we have all grown to care about over the last ten years! No spoilers here, I promise!

Poster for ‘Avengers, Endgame’ (Credit: Marvel / Disney)

However this post is about the ‘Avengers, Endgame’ the 22nd movie in the Marvel Cinematic Universe (MCU). Now while ‘Endgame’ is a direct sequel to ‘Avengers, Infinity War’ each of the previous 21 movies have contributed to the overall story arc if only, as in the recent ‘Captain Marvel’ by adding a new character who plays a role in ‘Avengers, Endgame’.

The First ‘Iron Man’ movie is considered the beginning of the Marvel Cinematic Universe (MCU) (Credit: Marvel Disney)

‘Endgame’ starts where ‘Infinity War’ ends, with the bad guy Thanos triumphant. Thanos has managed to possess all six infinity stones and used their power to eliminate half of all life in the Universe, which he thinks is a good thing to do. (The motive of Marvel villains may be strange but they are rarely just purely black.)

Obviously our heroes aren’t going to just let Thanos win. So ‘Endgame’ begins when the remaining Avengers, who happen to be the original six, are joined by Captain marvel and together they go after Thanos to get back the infinity stones in order to use them to bring everybody back. Unfortunately Thanos has used the stones to destroy the stones and I’m not going to go any further, you’ll just have to go see the movie!

And plenty of people are going to see ‘Endgame’. As I write this it’s just been announced that the movie is now the second highest grossing movie of all time, and it’s only been out for ten days. It seems to be only a matter of time until ‘Endgame’ takes the top spot from 2009’s ‘Avatar’.

James Cameron’s ‘Avatar’ currently holds the record as highest grossing film of all time. But for how much longer? (Credit: 20th Century Fox)

Without giving too much away I would like to mention a couple of the subplots within ‘Avengers, Endgame’. The first concerns the relationship between Iron Man and Captain America, arguably the two most central members of the Avengers. (Thor is an alien with his own home planet and Bruce Banner doesn’t want to be The Hulk). From the first time they met these two superheroes have had a bit of a completion over just who was the group’s leader. Steve Rogers (Captain American) is the old fashioned kind of commander, all courage and an iron will while Tony Stark (Iron Man) is a modern leader, all brains and technology.

The conflict became open war in the movie ‘Captain America, Civil War’ and ‘Endgame’ is in fact the first time the two have been together since then. Their first meeting is tense but later on the two are forced to go off alone together for 15-20 minutes and almost without their even noticing it they settle their differences and become comrades once again.

The conflict between Captain America and Iron Man came to a climax in ‘Captain America, Civil War (Credit: Marvel / Disney)

The second subplot is the whole question of whether a superhero can have a personal life. In previous movies in the MCU the superhero Hawkeye had basically retired to be with his wife and children, he was the only original member of the Avengers not to appear in ‘Infinity War’. Hawkeye returns in ‘Endgame’ only because Thanos’ use of the infinity stones has eliminated his family.

So not only is Hawkeye fighting to get his family back but during the course of ‘Endgame’ Iron Man, Captain America and Black Widow are all faced with the effect being a superhero has had on their personal life. This subplot is particularly poignant today because our society is wrestling with the problem of how much we demand from the members of our military and police, the cost to their personal lives for protecting us.

Members of the Military are often separated from their loved ones for long periods of time. This is a sacrifice they gladly accept to serve the greater good! (Credit: Military One Source)

This layer of real life social and psychological conflict has always been a hallmark of Marvel. Whether it be superheroes who don’t want to be superheroes or those whose flaws make them seem more human than superhuman. ‘Avengers, Endgame’ may really be just a comic book made into a movie but somehow the Marvel characters seem like normal, relatable people despite their comic book superpowers.

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The Dangers posed by certain foods, habits and environmental conditions to our health are often uncovered by large-scale studies of a significant portion of the population. The harmful effects of smoking, the long term damage caused by even low levels of lead in drinking water, these threats to our health and many others were first detected in studies of thousands if not millions of people.

The Surgeon General’s Warning came about because of large scale studies of the effect of Smoking (Credit: Everett Herald )

The basic idea is simple: quantify the health of a large number of people who are exposed to a factor being studied, and compare it to the health of a similar sized group of people who are not exposed. The health risks of smoking, pollution, obesity or even just sitting in a chair too many hours a day can then be determined by the use of statistical analysis.

Now noted Professor Jonathan M. Metzl, director of the Center for Medicine, Health and Society at Vanderbilt University has conducted three separate studies related to the effects on health of a very unusual and highly controversial factor, being a White Person! The results of these studies are detailed in Doctor Metzl’s new book “Dying of Whiteness’.

Noted Scholar Professor Jonathan M. Metzl (Credit: Vanderbilt University) The Cover of ‘Dying of Whiteness by Jonathan M Metzl (Credit: Basic Books)

The thesis of “Dying of Whiteness’ is that in today’s America millions of White, middle class people in this country are, in order to ‘maintain our way of life’, supporting conservative political ideologies that are actually harmful to their health and life expectancy. In support of his thesis Dr. Metzl examines three different aspects of conservatism in three distinct locations: 1.) Gun Laws in the state of Missouri. 2.) Health care in Tennessee, in particular opposition to the Affordable Care Act (ACA) also known as Obamacare. 3.) And finally the state of Kansas’ experiment in drastically cutting taxes in an effort to stimulate the economy and the resulting cutbacks in public services, everything from schools to highway upkeep.

Some proposed gun laws are now bordering on the ridiculous (Credit: Imgur)

I have written several posts previously (see my posts of 21 and 24Feburary and 19December 2018) on gun violence in this country and specially pointed out the shockingly high levels of suicide in this country. The plain fact is that in the United States twice as many people use a gun to kill themselves as to kill another person. Dr Metzl confines himself to the suicide aspect of gun violence, analyzing the situation in three ways: 1.) Examining the changes in gun legislation and policy in Missouri over the last 25 years. 2.) Relating anecdotal evidence gathered through interviews that illustrate the effects of suicide on those left behind. 3.) Comparing the actual statistical suicide rates in Missouri over the last 50 years.

Based on the evidence Dr. Metzl, who grew up in Missouri himself, forcefully concludes that the conservative political ideology, based on the desire to maintain white privilege, is actually adversely affecting the health of white people! To illustrate I’ll just quote one statistic, a white male buying a handgun to protect his home is eight times more likely to kill himself with that handgun than he is to ever kill an intruder. Instead of ‘Making America Great Again’ contemporary conservative policies are benefiting only the very rich while inflicting great harm to the majority of Americans, even white Americans.

There is a clear link between Gun Ownership and Suicide Rates (Credit: Politics that Work)

A similar story is told for the condition of health care in Tennessee, which adamantly refused to accept the ACA for purely political reasons. The effect of the decision is analyzed by comparing Tennessee’s abysmal health care to that of its neighbor Kentucky, which choose to accept both the ACA and the expansion of Medicade that accompanied it.

Again both anecdotal and statistical evidence is presented detailing how lower class citizens in Tennessee are suffering and dying for lack of proper medical attention when compared to the citizens of Kentucky. This goes even for those lower class white citizens who voted for the politicians who refused to allow the ACA in their state.

Some of the consequences of Tennessee’s refusal to accept Obamacare (Credit: Healthinsurance.org)

In one of the most heart breaking stories in the book Dr. Metzl relates the tale of Trevor, as is common in psychological studies Dr. Metzl does not use the real names of those he interviews. Trevor is slowly dying of an inflamed liver, a particularly painful way to die, brought on by a life of heavy drinking and hepatitis. If Trevor lived in Kentucky he would be eligible for drugs or even a liver transplant but in Tennessee he has no health care and cannot afford treatment. He still opposes Obamacare however, saying, “…no way I want my tax dollars paying for Mexicans and welfare queens.” Trevor is willing to die rather than support a system that would equally benefit both him and minorities.

In the final section of ‘Dying of Whiteness’ Dr Metzl discusses the State of Kansas’ recent and radical experiment in low taxes and small government. There had been a time not so long ago, when Kansas had been a model of good government, good roads, well-maintained parks and especially good schools. For decades Kansas public schools and colleges were ranked as the best in the mid-western United States.

That was before Governor Sam Brownback and the Tea-Party dominated GOP began their austerity program. State taxes were slashed in order to promote economic growth and ‘cut waste in government’.

Kansas Gov. Sam Brownback began a revolution in conservative government (Credit: AP Photo/Orlin Wagner)

It wasn’t long before the state was forced to cutback drastically in public services. Ironically these cutbacks forced local governments to increase taxes so that before long it was only corporations and the very rich who were actually benefiting from the low state taxes.

The resulting effect on schools was disastrous. State wide test scores dropped while dropout rates increased. The reduction in school funding was so extreme that teachers were often forced to spend their own money to obtain necessary school supplies. Kansas’ once exemplary public services were sacrificed to a conservative ideology that had been supported by lower class whites but which did them the same harm as it did to those minorities that they had accused of abusing the public welfare system.

One Piece of good news. Kansas’ new Governor Laura Kelly is a democrat who is determined to end the radical cutback in state services (Credit: People’s World)

‘Dying of Whiteness’ is not a pleasant book to read, hard truths are rarely pleasant things to face. However it is a very important and powerfully written book on current political policies here in the United States and increasingly elsewhere in the world. With the Trump administration’s current legal attempts to eliminate the ACA completely, while at the same time having no plan for any replacement it is a fair bet that over the next few years many more people will be ‘Dying of Whiteness’!

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Very few people taking an airline flight ever stop to consider all of the different conditions under which an airplane wing has to perform. Takeoffs, cruising at altitude, maneuvering and landing are all situations that put very different demands on aircraft wings and require different wing shapes in order to perform most efficiently. Of course an aircraft can’t change its wings in the middle of a flight so current wing designs are a compromise that with the addition of airfoils and flaps succeed in doing an adequate, if not optimal job.

Now NASA’s Ames Research Center is teaming with the Massachusetts Institute of Technology (MIT) to develop an entirely new kind of aircraft wing that can literally morph its shape while in flight. The technology is known as MADCAT or Mission Adaptive Digital Composite Aerostructure Technologies and testing is nearing completion at Ames’ wind tunnel on a four-meter wide prototype model wing. See image below.

Scale Model of Morphing Wing undergoing testing at NASA’s Ames Research Center’s Wind Tunnel (Credit: NASA, MIT)

The new technology begins by constructing the wing in an entirely new, modular approach. As seen in the images below, each individual module in the design is an eight-sided octahedron composed of carbon fibers that can be formed by injection molding in only 17 seconds, making them very cheap to produce in quantity. The interior of the wing is then built up of a lattice of these modules.

The Octagon shape of each module of the Morphing Wing can be easily Manufactured (Credit: NASA, MIT) Morphing Wing under construction (Credit: NASA, MIT)

The modular lattice so constructed is highly flexible and when covered with a layer of polymer material the wing can morph its shape in order to optimize its aerodynamic properties. Needless to say Computer control of every module is an essential part of the morphing process.

However a single central computer having to process the data from all the necessary sensors, which are spread over the surface of the wing, would simply take too long to make the required decisions. Therefore a distributed approach to wing control is employed so that each module can alter its shape in order for the entire wing to adapt.

Despite its complexity the MADCAT wing should actually be simpler to manufacture and repair since each module is identical. The MADCAT wing is also lighter and can be even stronger depending on the material from which it is cobstructed.

Another potential advantage to the radical new design for aircraft wings is that it may finally spur aviation companies to switch from the traditional cylindrical fuselage with wings aircraft design to an integrated body-wing design that has long been known to be more efficient. Over the last 60-70 years there have been several airplanes to have used that design, the images below are of the flying wing and B-2 stealth bomber. Aircraft manufacturers are conservative however, and rightly so given the inherent dangers of flying. In addition to safety concerns there will also be the cost of switching to an entirely new way of manufacturing airplanes.

The 1950s Version of a Flying Wing. The Northrop YB-49 (Credit: YouTube) A B-2 Bomber also uses the flying wing approach (Credit: USAF)

The new MADCAT wing could be just the thing to change their minds. As you can see from the first image at the top, the modular wing approach is just perfect for a flying wing airplane design and the tremendous increase in efficiency the combination would provide could be more than aerospace companies can resist.

Speculative Design for a future Flying Wing that could employ the Morphing Wing Technology (Credit: CNN, Stephan Chang)

The future looks bright for MADCAT but there could be a long way to go before you will be flying anywhere on a morphing wing airplane.

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Nowadays we’ve become accustomed to having unmanned, robotic space probes traversing interplanetary space and making important discoveries without there being any human within millions of kilometers. At the beginning of the space age however there were many, even respected scientists who doubted that automated mechanisms could carry out the complex maneuvers, over long periods of time, that would be required for missions to the Moon or nearby planets.

Science fiction movies of the 1920s through the 50s had always depicted the first landings on alien worlds being made by manned, piloted spaceships not robots. Robots after all could only do what they were programmed to do, they would never be able to deal with unforeseen events; they could never be adaptable enough to face the unknown.

In George Pal’s ‘Destination Moon’ the first landing on the Moon was Manned (Credit: George Pal Productions)

Nevertheless the cost of getting a man into orbit, let alone to another world was so great that manned flights to other planets were simply not possible. After all a person would require air throughout the mission, would require food and water, would have to be brought back! Robots on the other hand only needed electricity and it didn’t matter if they didn’t return to Earth, just so long as their data did!

So it was that the first man made object to leave Earth orbit, the first to completely escape from Earth’s gravity was a robotic probe. Launched on January 2nd, 1959 Luna 1 was another space first for the Soviet Union although the probe failed in its objective of crashing into the Moon. Think about that, with all of the complex maneuverings and operations that space probes carry out today the first deep space probe just had to hit the Moon, and it missed.

The Luna 1 probe was the first Man Made Object to leave Earth orbit. (Credit: Roscosmos)

So did the first American Lunar probe Pioneer 4, launched just two months later, Pioneers 1-3 all blew up on the launch pad. The first deep space probe to actually succeed was Luna 2 on September 13 of 1959.   A month later in October Luna 3 successfully passed behind the Moon, taking a picture that was radioed back to Earth giving humanity its first glimpse of the far side of the Lunar farside.

One of the Images of the Moon’s Farside sent back by Luna 3 (Credit: Roscosmos) The Luna 3 Space Probe (Credit: Roscosmos)

Thanks to the power of their R-7 rocket the Soviet’s were also the first to attempt a mission to another planet. A pair of space probes called the U1 and U2 were launched on October 10th and 14th of 1960. The mission intended for the two probes was a fly-by of Mars but neither managed to even leave Earth orbit.

There were a lot of failures in those early days, launch failures, failures to leave Earth orbit, or failures where the probe would miss its target. And even if the spacecraft did make it to its intended destination there could be a loss of radio contact. It was beginning to look as if the nay Sayers were right, robotic space missions were simply too complicated, there were just too many unknowns for a mere machine to handle.

The US space probe Mariner 4 changed that. Launched from Cape Canaveral on November 28th of 1964 the Jet Propulsion Laboratory (JPL) built space probe successfully flew past the planet Mars on the 14th of July 1965. At its closest approach of 13,000 kilometers the Mariner probe took a series of 22 images of the surface of the Red Planet. These images were transmitted back to Earth over the next few days.

A Replica of Mariner 4 (Credit: JPL-NASA)

By today’s standards the images were poor, the last three missed the planet entirely while only a dozen are really clear enough to be useful. Those images were revolutionary however showing scores of craters spread across the Martian surface. The data sent back by Mariner 4 showed a Mars that resembled Earth’s Moon a great deal more than any astronomer had imagined. All of the speculation of Martian civilizations building a system of canals vanished in an instant. With a single successful mission the scientific value to science of robotic interplanetary probes had been demonstrated.

One of the Images of Mars sent back by Mariner 4 (Credit: JPL-NASA) Perhaps the best image sent back by Mariner 4 (Credit: JPL-NASA) The Location of the images taken by Mariner 4 on the surface of Mars (Credit: The Planetary Society)

It also so happened that following Mariner 4 robotic probes became more reliable, more successful. The engineers were learning from their mistakes designing probes that could survive the hostile environment of deep space.

The American Surveyor 1 and Lunar Orbiter 1 Moon probes became the first man made objects to respectively land softy on, and orbit another world. Meanwhile the Soviet Venera 3 became the first to impact on the planet Venus and Zond 5 circled around the Moon and became the first interplanetary probe to return to Earth.

The Surveyor Lunar Lander Space Probes (Credit: JPL-NASA) The Zond 5 Space Probe after completing its mission of traveling around the Moon and returning to Earth (Credit: Roscosmos)

Since Mariner 4 success for automated space probes has become the norm. There are still failures on occasion, but by now every planet in our solar system, along with moons, comets and asteroids have all been visited by unmanned, robotic probes.

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Since the idea that an asteroid collision with the Earth was responsible for the extinction of the dinosaurs was first proposed over forty years ago by Walter Alvarez the evidence for such a catastrophe has accumulated slowly but surely. Alvarez based his original idea on evidence collected during his own examinations of the K-t boundary at numerous locations around the world. (The K-t boundary is the layer of rock strata that marks the end of the dinosaurs, below the boundary is the Cretaceous period rich in dinosaur fossils, above it is the Tertiary period with absolutely none! The K-t boundary is dated to some 66 million years ago.)

Walter Alvarez (r) standing with his Father Nobel Prize Winning Physicist Luis Alvarez (l). Walter has his hand on the rock layer that is the k-T boundary (Credit: Wikipedia)

What Alvarez found at the K-t was a very thin layer of rock rich in the element iridium, which is very rare of Earth but much more common on meteoroids. It was this thin layer that led him to speculate that an asteroid; perhaps 10 kilometers in diameter had struck the Earth triggering a worldwide extinction.

Then in 1978 the actual crater, now named Chicxulub, formed by that asteroid was identified centered just off shore of the Yucatan peninsula of Mexico. Evidence from that crater confirmed that the amount of energy released by that collision was indeed sufficient to cause mass destruction around the world. Additionally, evidence of rocks distorted by high temperature and pressure and material thrown about by enormous tsunamis has been found throughout both North and South America. Still, some researchers have asked, if the dinosaurs, and many other creatures became extinct in such a violent episode, shouldn’t we be able to find a mass graveyard showing some unmistakable signs of such an event.

Location ans Size of the Crater caused by the Asteroid that killed the Dinosaurs (Credit: Kut.org)

Now a team of paleontologists from the University of Kansas has announced the discovery of a fossil site that provides just the smoking gun they were looking for. Led by paleontologist Robert DePalma the site is called Tanis and is located in the Hell Creek Formation in the southwestern corner of North Dakota.

Rock section of k-T boundary taken From Tanis Fossil Site. Thin middle layer contains 1000x as much Iridium as upper and lower layers. Credit: Wikipedia)

The fossils recovered from the site consist of a mashup of freshwater and saltwater animals and plants that appear to have all perished in a very short period of time. More telling however was that some of the fish were found to have small, glass like balls of compressed and heated rock imbedded in their gills as if they had breathed them in. These small rocky balls are known as tektites, a common product of volcanic activity or an asteroid strike. The fact that these tektites were found more than 3,000 kilometers from where the asteroid struck is a testament to the power that had been unleashed.

Some of the fossilized fish killed by the asteroid strike and uncovered at the Tanis fossil site (Credit: Science News) Prepared Microscopic Slide from a fossil at the Tanis site showing tektites (Credit: Robert DePalma)

So complete and well defined are the remains from the Tanis site that the paleontologists believe that they can actually make out the sequence of the events that occurred there. It appears that first came a tremendous seismic surge, an earthquake of such power as to dwarf any in recorded history. This geologic upheaval began the mixing of fresh and saltwater environments that continued when a massive tsunami followed some 16-18 hours later. Finally, over a period of days or even months a thick layer of ash would have fallen from the skies covering the dead and dying animals, leaving them for us to uncover 66 million years later.

This photo taken and handout on March 29, 2019 by the University of Kansas,shows Robert DePalma(L)and field assistant Kylie Ruble(R) excavate fossil carcasses from the Tanis deposit.The site appears to date to the day 66 million years ago when a meteor hit Earth, killing nearly all life on the planet. (Photo by Robert DePalma / Kansas University / AFP)

It is true that no dinosaur fossils have been discovered at Tanis so far; the site appears to have been a shallow water environment. Still one may turn up whose body got washed into the area. If not sooner or later we’ll find another site that has dinosaurs, it’s only a matter of time, and time is one thing this old Earth has got plenty of.

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This past month there have been a number of successes and failures in space along with a story that reminds us that spaceflight can sometimes just be fun. So let’s get to it.

As usual I’ll start with Space X, doesn’t it seem to you as if Elon Musk’s company provides us with some news to discuss every month. On April 10th the Hawthorn California based Space X successfully flew its Falcon Heavy launch vehicle for the second time, and for the first time with a paying customer.

The Second Launch of a Space X Falcon Heavy on its first commercial mission (Credit: New Scientist)

The Falcon heavy not only succeeded in placing the Arabsat 6A into its proper geostationary transfer orbit but Space X succeeded in recovering all three booster engines and even the launch vehicle’s payload nose cone failings. The two side boosters landed safely back at Kennedy Space center while the central first stage was recovered by Space X’s drone recovery ship “Of course I still love You”.

The Falcon Heavy side boosters return to Cape Kennedy (Credit: Wikipedia)

Recovery of the nose cone, which costs about $6 million dollars for a pair, is something that Space X has attempted several times before now without success. The nose cone recovery therefore makes the April 10th launch represents the most complete recovery that Space X has ever carried out.

Unfortunately on the day after the nearly perfect launch choppy seas in the Atlantic Ocean caused the central first stage to tip over and crash onto the recovery ship as it was being brought back to port. This is the first time that a Falcon first stage has been loss after successfully landing on the recovery ship and Space X promises design changes to their method of securing the rocket during transit to prevent further such losses.

The Falcon Heavy first stage landed safely on its recovery ship but heavy seas the next day caused it to tip over (Credit: Michael Howard)

A little further out in space Israel was having considerably worse luck. Their Beresheet lunar lander would have made the small Middle Eastern nation only the fourth country to achieve the feat of soft landing a probe on the Moon but unfortunately the Beresheet landed much too hard and presently is considered a total loss.

The Israeli Beresheet Lunar Lander attempted a soft landing on the Moon (Credit: The Planetary Society)

Although developed by Israeli tech companies Beresheet is the first ever privately funded lunar lander. Launched aboard a Space X Falcon 9 rocket back in February the Beresheet entered a highly elliptical orbit around the Earth, slowly enlarging that orbit until the lunar probe broke free and headed for the Moon.

The Journey of the Beresheet Lunar Lander was a long and complicated one (Credit: Space Ref)

The probe did make a number of observations on its journey including a video of the Sun appearing from behind the Earth. Nevertheless the failure to land safely is a disappointment. The Israelis haven’t given up however; money is already being raised to begin construction of Beresheet 2.

Further out in space the Japanese were having better luck with their Hayabusa 2 space probe now in orbit around the asteroid Ryugu. After several months of surveying the asteroid for the best location from which to obtain samples of the asteroid’s interior the space probe deployed a projectile to strike the asteroid. The idea was for the Hayabusa 2 to fire a small copper plate referred to as an impactor at Ryugu and as it approached the surface a small explosive would detonate which would drive the plate into the asteroid forming a crater. After the crater was formed the spacecraft would then approach and collect the desired samples.

The Small Carry-On Impactor aboard the Hayabusa 2 (Credit: Spaceflight 101)

The operation went off perfectly on April 4th, see image of the impact below, with the impactor striking Ryugu at an estimated 7200 kph. Now Hayabusa’s controllers must gently lower the probe toward the asteroid in order to collect some samples. The Hayabusa 2 is scheduled to return to Earth with its asteroid pieces in December of 2020.

The strike of the Hayabusa Impactor (Credit: Space News)

My final story today is a reminder that even as humans traveled into space we took other creatures along with us. Indeed, Laika the dog preceded the first man into space by a couple of years. The use of test animals in space exploration has a long and interesting history.

Today on the International Space Station (ISS) there are several different experiments involving lab animals being conducted at all times. One of these uses lab mice to study the long-term effect of zero gravity and radiation.

The Rodent Habitat aboard the ISS (Credit: NASA, Dominic Hart)

“Since rodents develop and age much faster than humans, studying rodent model organisms allow scientists to study diseases that may take years of decades to develop in humans.” According to lead researcher April Ronca, a biologist at NASA’s Ames Research Center in California. The space agency has even designed a special habitat for the test subjects. The habitat is large enough for the mice to be able exercise and even just play, and they certainly enjoy playing. Check out the video by clicking on the link provided below. They have certainly learned how to enjoy Zero gee.

https://www.youtube.com/watch?v=q7lgj3aZ8dU

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First Picture of a Block Hole (Credit: Event Horizon Telescope Collaboration)

Yes it’s true; you can’t see a black hole. The glowing doughnut shape in the image above is actually the swirling mass of gas and dust that is falling into the black hole. Astronomers call that whirlpool an accretion disk and the energy released by that matter as it drops into the gravitational well of the black hole causes the disk to glow. Also, the actual image that you see above wasn’t really taken in visible light. Rather it’s a computer-generated image converted from measurements of radio emissions across the region around the black hole.

In fact it took eight radio telescopes and more than three hundred astronomers working together in a group known as the Event Horizon Telescope Collaboration to collect the signals from the black hole needed to construct the image. The eight radio telescopes which make up the Event Horizon Telescope (EHT) are spread around the half the world; see map below. By combining the received signals of those telescopes the astronomers succeeded in constructing a single radio telescope whose resolution was equivalent to a telescope that would be nearly the size of the Earth. (The resolution of a telescope is its ability to separate two objects that are both very far away and very close together.)

The Eight Radio Telescopes that were combined to produce the Black Hole Image Span half the World (Credit: EHT)

The technique used to combine the eight signals is know as Very Long Baseline Interferometry (VLBI) and networks the telescopes by adding their signals together, allowing them to interfere with each other, remember these signals are waves, exactly as they would in a telescope as big as the distance between the telescopes. In order to add the signals together properly they must have been received at precisely the same time. This means that each radio telescope in the EHT must be governed by its own atomic clock, and all eight atomic clocks must have been synchronized before the first signals were received.

The Combined Array for Research in Millimeter-wave Astronomy (CARMA) is just one of the eight telescopes that make up the Event Horizons Telescope (Credit: University of Chicago, Department of Astronomy and Astrophysics)

That degree of precision was necessary because the black hole whose image was taken sits 55 million light-years away in the galaxy known as M87 or Virgo A and the size of the black hole is about the same as the orbit of Pluto while the size of the accretion disk is about eight times larger. In addition to producing the image the measurements made by the EVT allowed a more precise measurement of the black hole’s mass, a whopping 6.5 billion times the mass of our Sun.

The Galaxy M87 which contains the first Black Hole ever Images (Credit: The Daily Galaxy)

All that work was certainly worth the effort. That one image confirms much of the theoretical work that has been conducted regarding black holes over the last thirty to forty years. The black hole’s event horizon, the energy emitted by the accretion disk as matter flows into the black hole, they’re all there, just as the models predicted.

What the Theories said a Black Hole looked like. Turned out they were Right! (Credit: Science)

The importance of the image is that it confirms one of the strangest predictions of Einstein’s General Theory of Relativity, the very existence of black holes. Now however, the researchers hope to use the EVTC to probe closer to the event horizons of black holes in order to test the limits of the General Theory. Even after one hundred years physicists have still been unable to integrate General Relativity with Quantum Mechanics, the other great theory of modern physics. The possibility that observations of black holes by the EVT may discover some clue leading to that unification is very enticing.

The astronomers also hope to learn more about the supermassive black holes that sit in the center of every galaxy. At the moment we don’t even know for certain which comes first, the galaxy or the black hole in its center but there are theories of galactic evolution that start in both directions. Maybe EVTC will find the evidence to answer that question.

As their next step the members of the EVTC are planning on trying to obtain images of the black hole that sits at the center of our own galaxy. Since our black hole is a lot closer, only 30,000 LY away you might wonder why the astronomers didn’t start with our black hole. You have to remember however, that to see the center of the Milky Way you have to look through most of the galaxy’s disk. In other words that black hole may be closer but there’s a lot more stuff in the way!

Looking towards the center of the Milky Way there’s a lot of other stuff between us and that Black Hole (Credit: Harvard CfA)

So the first image of a black hole that was taken by the EVT is really just a first step. There are many black holes to be studied out there, which means many more discoveries just waiting for the EVT to make.

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