Space News for November 2017

There have been several very interesting things happening in space this past month so we’ve got a lot to discuss. I almost don’t know where to start.

I’ll start with the discovery of the second closest exo-planet, that is a planet orbiting another star. The star is called Ross 128 and sits in the constellation of Virgo at a distance of 11.2 Light Years (or 3.4 Parsecs) while the planet has been designated as Ross 128b.

Not only is Ross 128b close to earth it’s also just 35% more massive than our Earth so it’s expected to be a rocky planet. In addition Ross 128b orbits its star at a distance within what astronomers call the habitable zone. The habitable zone is defined as the region of space where the light coming from a star is just strong enough to give a planet a surface temperature suitable for liquid water to exist. And liquid water is obviously a prerequisite for life similar to that here on Earth.

How far the habitable zone is from a star depends on how much energy the star emits every second. A large hot star like Sirius would have its habitable zone out where Jupiter or Saturn are in our Solar System but Ross 128 is a small dim star; its habitable zone is much closer than even the orbit of Mercury. In fact Ross 128b is so close it orbits Ross 128 every 9.9 days!

One more thing about Ross 128b that has astronomers excited is that its parent star is a calm mild star, not prone to flare-ups that could make life impossible on their planets. Based on what we know about Ross 128b the planet looks like the best bet right now for discovering life outside our Solar System.

And we may be doing just that quite soon. You see over the next few years a new generation of telescopes, collectively know as Extremely Large Telescopes (ELTs) will begin to study the Universe. These huge instruments, along with the James Webb space telescope to be launched next year, should be able to separate Ross128b from the glare of its parent star and possibly detect signs of life on its surface. Detecting the spectral lines of Oxygen in the planets atmosphere in particular would be very strong evidence of life. Sometime in the next ten years we may know for certain! The image below shows an artist’s idea of what the Planet Ross 128b may look like along with artwork from NASA of the James Webb space telescope.

Imagined view of Ross 128b (Credit: M. Kornmesser)
James Webb Space Telescope (Credit: NASA)

The second story is related to the first because it concerns another close, potentially inhabited exo-planet orbiting around Luyten’s star at a distance of only 12 light years. The planet GJ273b is about three times the mass of Earth and also orbits within the habitable zone of Luyten’s star.

A new organization called METI, Messaging Extra Terrestrial Intelligence, has begun sending radio signals, including music, to any potential civilization on GJ273b using a radio telescope in Norway starting in October and will be repeated in April of 2018. Traveling at the speed of light the signals will arrive at GJ273b in November of 2030. If there is a technical civilization on GJ273b then we may hear an answer in 2043. The image below shows the EISCAT parabolic dish antenna used to transmit the signals to GJ273b.

EISCAT Radio Dish (Credit: EISCAT)

Finally I like to talk a little more about one of those new telescopes that could revolutionize our knowledge of the universe. The Zwicky Transient Facility (ZTF) may not be the largest astronomical instrument but its digital camera, with a resolution of 24,000 by 24,000 pixels, will be capable of scanning the entire northern sky each night for transient events, anything that changes in brightness.

ZTF will quickly spot and localize objects ranging from supernovas to Near Earth Asteroids to supermassive black holes devouring entire stars in other galaxies. ZTF is also expected to detect the visible components of gravity wave events. Whenever ZTF spots something of interest other, more powerful but narrower focused instruments will be brought to bear to study the event in greater detail.

The ZTF telescope took its first photograph on November 14, see image below, and will be fully operational next year. If you’d like to read more about the ZTF click on the link below to be taken to the University of Maryland’s ZTF website.

First Image from ZTF (Credit: Caltech Optical Observatories)

https://cmns.umd.edu/news-events/features/4026

These are just a few more reasons to think that we could be in for some very exciting discoveries over the next few decades!

 

 

 

Have Scientists taken a critical step in understanding the Chemistry of how life began and an update on our Interstellar Visitor.

Ever since Charles Darwin’s ‘On the Origin of Species’ had demonstrated that all of the multiform types of living creatures here on Earth had evolved over millions of years from a single primitive type of life scientists have sought to understand how that first living thing came into being. Much has been learned in the last 150 years but many of the details of the chemistry involved in the development of a complex, self-replicating molecular system, i.e. a simple living cell, are still unknown.

Now researchers at The Scripps Research Institute (TSRI) have published a paper in which they claim to have found a chemical compound that played a key role in assembling short nucleotide chains (early genetic material) with peptide chains (short version of proteins) encapsulated in a lipid vesicles (early cell walls). Finding a catalyst that could combine these three distinct types of chemicals, and which could have existed on the primitive Earth has been a goal of ‘Origins of Life’ researchers for the past several decades.

The scientists at Scripps have given their compound the name diamidophosphate or DAP for short and have published their results in the journal ‘Nature Chemistry’. The figure below shows the chemical diagram and the structure of DAP.

Chemical Formula for DAP (Credit: Ramanarayanan Kirshnamurthy)
Structure of DAP (Credit: Ramanarayanan Krishnamurthy)

According to lead researcher Doctor Ramanarayanan Krishnamurthy DAP “would have allowed other chemistries that were not possible before, potentially leading to the first simple, cell based living entities.” “With DAP and water and these mild conditions, you can get these three important classes of pre-biological molecules to come together and be transformed, creating the opportunity for them to interact together, ” Krishnamurthy said. The image below shows DAP and the three classes of chemicals needed to build a simple cell.

DAP linking three classes of pre-biological complex compounds (Credit: Ramanarayanan Krishnamurthy)

Whether or not DAP was THE chemical catalyst that enabled the formation of the first living cell will be difficult to prove four billion years after the fact but Dr. Krishnamurthy and his co-authors intend to continue their study of DAP and other phosphorylating compounds. If you’d like to read the press release put out by the Scripps Institute click on the link below.

https://www.scripps.edu/news/press/2017/20171106krishnamurthy.html

Before I go I’d like to take a moment to update one of my posts of just last week (4Nov17) about the interstellar visitor that entered our solar system and is now on its way back into the void between the stars. Well A/2017 U1 has been given the new name of 1I Oumuamua. The 1I indicates that it is the first interstellar object ever discovered while Oumuamua is a Hawaiian word meaning scout or Messenger. 1I Oumuamua was discovered by the Pan-STARRS telescope in Hawaii after all. The image below shows Oumuamua’s path through our solar system.

Path of 1I Oumuamua through our Solar System (Credit: NASA-JPL-Caltech)

 

More importantly a group of Astronomers are preparing a paper in which they give their estimate as to the place of origin of Oumuamua along with how long it took to reach our solar system. Working backward along the trajectory of Oumuamua Eric Gaidos and Jonathan P. Williams of the University of Hawaii along with Adam Kraus of the University of Texas are of the opinion that Oumuamua originated in the Carina and Columba Associations, clusters of young stars at a distance of 215 to 365 light years. (Carina and Columba are constellations in the southern sky).

Current research estimates that the Carina and Columba Associations were an active star-forming region about 45 million years ago. If Oumuamua had been thrown out of a newly forming solar system in the direction of our Sun at a velocity of 1-2 kilometers per second it could just now be arriving in our solar system!

Even though Oumuamua was only near enough for us to study it for about a month we have already learned a great deal from it. This is only the start, in the years to come I have no doubt that we’ll be learning a great deal more.

 

 

Star Talk on National Geographic Channel: Neil deGrasse Tyson interviews the Former Head of DARPA, Arati Prabhaker.

Last Sunday night, 5November17, the National Geographic channel broadcast the latest episode of their series ‘Star Talk’, the ‘Intersection of Science and Popular Culture’ with host Neil deGrasse Tyson. As always the show centered around a taped interview by Dr. Tyson with a guest of some importance in some field of science. Last night’s guest was Doctor Arati Prabhaker who recently stepped down from her position as the Head of the Defense Advanced Research Programs Agency or DARPA. The picture below shows Dr. Tyson with Dr. Prabhaker.

Neil deGrasse Tyson interviews Arati Prabhaker (Credit: Star Talk, National Geographic Channel)

The interview began with Dr. Tyson asking Dr. Prabhaker to describe what DARPA is and relate a bit about its history. DARPA was formed in 1958, in the wake of the USSR’s launching the first artificial satellite Sputnik I, as an agency within the Department of Defense assigned with finding ways to adapt the latest technology to our nation’s military readiness.

Over the years DARPA has had a few amazing successes such as ‘Stealth’ radar invisible aircraft and precision guided ‘Smart Bombs’ but not all of DARPA’s work has involved weapons. In fact some of the agency’s breakthroughs have been turned into many of the hi-tech devices we use everyday. One DARPA program called ‘ARPA net’ developed many of the protocols that computers use to talk to each other, a critical part of the Internet. Also, I was personally a witness to DARPA’s funding of the development of Gallium Arsenide (GaAs) as a semiconductor material for high frequency circuits; you wouldn’t have a cell phone without it.

In fact some of the technology currently being supported by DARPA has already been discussed on this blog in previous posts. The DARPA challenge race for driverless cars was the main topic of my post of 17Jun17. Meanwhile DARPA’s funding has also helped to advance the engineering of prosthetic limbs for wounded soldiers, some of the results of which were discussed in my post of 23Sept17. The images below show some of the results of DARPA’s support in these fields. The first is from the driverless vehicle challenge while the second shows the latest result of prosthetic engineering and which is currently undergoing clinical trials by the Food and Drug Administration.

 

Winner of DARPA Challenge from Stanford University (Credit: Stanford University)
Prosthetic Arm funded by DARPA (Credit: Star Talk, National Geographic Channel)

While Dr. Tyson’s interview with Dr. Prabhaker was taped earlier several guests joined Neil in his studio at the Hayden planetarium. One was his usual sidekick the comic Chuck Nice who seemed unnaturally nervous while trying to make jokes about military weapons systems. The second guest was the journalist Sharon Weinberger who has reported about DARPA for 17 years and has written a book ‘The Imagineers of War’ about DARPA. The cover of ‘The Imagineers of War’ is show below.

The Imagineers of War by Sharon Weinberger (Credit: Amazon.com)

The episode’s final guest, Hod Lipson is a Mechanical Engineer who took part in DARPA’s road challenge with a team from Cornell University and who has written about the coming revolution in driverless cars appropriately titled ‘Driverless’. Both books are available at Amazon. The cover of ‘Driverless is shown below.

Driverless by Hod Lipson (Credit: Amazon.com)

At the end of every episode Dr. Tyson makes a few concluding comments. A few of the things he said last night bear repeating. First Neil suggested that there should be a DARPA type of agency ‘in every branch of human culture’. But the comment that I think we would all do well to consider was ‘at DARPA they take risks, risks that other sources of money do not take. Well the day you stop making mistakes is the day you can be sure you are not on the frontier.”

 

An Interstellar Visitor enters our Solar System. What is A/2017 U1 and what can we learn about what it is and where did it come from.

Over the past twenty years or so NASA has been working on a effort to find and catalog all of the small objects in our Solar System that could one day pose a threat to us here on Earth. A critical part of this effort was the design and construction of telescopes especially suited to surveying large parts of the sky in very fine detail.

One of these telescopes is Pan-STARRS at the observatory atop Mona Kea in Hawaii. With a mirror of 1.8 meters in diameter the telescope is smaller than most professional instruments, but with a 1.4 Gigapixel camera Pan-STARRS can photograph the entire sky several times a month.

That’s what you need in order to find Near Earth Objects (NEOs). Take two pictures of the same part of the sky a couple of weeks apart and compare them. Anything that moves between the two images is an NEO.

Just a few weeks ago on October 19th, Doctor Rob Weryk of the University of Hawaii’s Institute for Astronomy found something special with the Pan-STARRS telescope. At first Dr. Weryk thought he’d just found another

space rock, there are literally thousands out there. Dr. Weryk gave the 500-meter rock the designation A/2017 U1.

When he calculated the object’s position and velocity however Doctor Weryk realized that whatever it was it was moving too fast to remain in orbit around the sun. The object was a visitor from interstellar space making its first and only trip around our Sun. The photograph below shows the small dot that is A/2019 U1.

Interstellar Visitor A/2017 U1 (Credit: Alan Fitzsimmons, Isaac Newton Group)

 

Astronomers had long been expecting a visit from such an object. Many models of how solar systems form have a certain amount of matter being expelled as the star and planets condense. These outcasts would then wander between the stars where they could occasionally be drawn into the gravitational field of another star.

The orbits followed by these temporary visitors are not closed elliptical paths like those of planets or very comets but are an open-ended curve known as a hyperbola. Whereas the planets repeat the same orbit over and over again, an object on a hyperbolic trajectory is on a one time only orbit around a star. The figure below shows the difference between an elliptic and hyperbolic orbit.

Elliptic and Hyperbolic Orbits (Credit: R. A. Lawler)

A/2017 U1 made its closest approach to our Sun back on September 9th, more than a month before it was discovered. Coming within 23 million miles of our star A/2017 U1’s velocity increased to almost 90 kilometers per second. It passed within 15 million miles of Earth on October 14th at a velocity of 60 kps; three times the velocity that the New Horizons space probe had on its way to Pluto. In ten years or so, when it has left our Solar System behind A/2017 U1 will still have a velocity of about 25kps, faster than that of the Voyager I space probe, the first man made object to leave our Solar System. The image below shows the path of A/2017 U1 as it swung around the Sun.

Path of A/2017 U1 through our Solar System (Credit: NASA-JPL-Caltech)

So, what was A/2017 U1? What was it made of? Where did it come from?

To be honest we didn’t learn a great deal about A/2017 U1. It was very small, didn’t come that close and is already too far away for even the most powerful telescopes to see anymore. Really all we know for certain is that A/2017 U1 came from the direction of the constellation of Lyra and that it looked more like an asteroid than a comet.

But we know it came from the beyond, from outside out little neighborhood of the Galaxy. And that means there will be others, and each time one visits we will learn a little more about them. That’s the way science works after all.

Solar Eclipse of 1207BC helps to date Pharaohs? Interesting but I’m not so sure about the connection.

Back in August I was lucky enough to have had an almost perfect view of the recent total Solar eclipse that crossed the USA, (See Post of 24August17) so went I came across an article entitled “Solar Eclipse of 1207BC helps to date the Pharaohs” I was instantly intrigued. It only took me a few minutes to find and download the original article at the journal ‘Astronomy and Geophysics’. What I read was certainly interesting but also clearly displayed some of the difficulties in trying to use modern science to study ancient, semi-legendary records of past events.

The article was written by Colin J. Humphreys of Selwyn College at Canbridge University and Graeme Waddington, an independent scholar. What Humphreys and Waddington propose is that the astronomical miracle described the Old Testament book of Joshua (Joshua 10:12-14) was not as usually translated the Sun and Moon standing still at Joshua’s command but rather a description of a Solar eclipse.

This idea is not actually new. As Humphreys and Waddington themselves point out the linguist Robert Wilson realized over a hundred years ago that the Hebrew words dôm and ‘amad could also mean that the Sun and Moon stopped shining, i.e. an eclipse. However, when astronomers did the calculations to find that ancient eclipse they discovered that there was none appearing in Canaan around the right time.

What Humphreys and Waddington realized was that the earlier calculations of ancient Solar Eclipses ignored the possibility of the event being an annular solar eclipse. Now an annular eclipse occurs when the Moon is at the farthest point in its orbit and therefore appears smaller in our sky, too small in fact to completely cover the Sun leaving a bright annular ring of sunlight. See picture below.

An Annular Eclipse (Credit: The Cosmos Within)

Doing the calculations Doctors Humphreys and Waddington found that there had been an annular eclipse across North Africa and Canaan on the 30th of October in the year 1207 BC. This eclipse they claim is the miraculous event depicted in Joshua, chapter 10. The image below shows the path of the annular eclipse.

Path of Eclipse of 1207BCE (Credit: C. Humphreys and G. Waddington)

Now to the ancient Hebrews an annular eclipse of the Sun would still be more than spooky enough to be remembered and connected to their legendary hero Joshua. At this point however the authors indulge in some hand waving, just suppose type arguments to provide a little more evidence. For example they claim that the reduction in sunlight during the afternoon, followed by the return of light after the eclipse’s maximum and then concluding with a real sunset could very easily be described as “The Sun did not hurry to set for about a whole day” (Joshua 10:13 New Revised Standard Version or NRSV).

To me this is part of the problem of trying to use modern science to describe biblical or mythological stories IN DETAIL! These stories have been so elaborated, so dramatized that any historical reality is deeply buried. You have to massage the surviving evidence to make it appropriate for the scientific explanation you’re suggesting.

In fact the very existence of the biblical hero Joshua and the Israelite “conquest” of Canaan has been seriously called into question. Professor Israel Finkelstein of the Department of Archeology at Tel Aviv University has published a series of papers and books detailing a broad spectrum of evidence that the Hebrew people developed in situ, that is the Hebrews were originally Canaanites who developed a different culture and came to consider themselves a different people, not an outside people who conquered the central highlands region of Canaan. According to Doctor Finkelstein, the stories of Exodus and Joshua are simply that, stories. There is no archeological evidence to support them. Trying to connect an astronomical event to such “history” may be completely impossible.

(If you’re interested in leaning about Doctor Finkelstein’s work I heartily recommend his “The Quest for Historical Israel” available at Amazon)

Still, up to this point I was with Doctors Humphreys and Waddington, but then they made a connection that just went to far for me. At the time of their eclipse, 30Oct1207BC, the Pharaoh in Egypt was named Merneptah, the son and successor of the famous Rameses the second. Now it happens that we know the number of years these men reigned better than the actual dates. The first year of Mernephat’s reign is considered to have been anywhere between 1213BC to 1204BC.

However, Merneptah is also know for having inscribed a stone slab with details of his victories (such a stone slab is known as a stele), including his victory over Israel! The images below show the entire stele along with the section mentioning Israel.

Merneptah’s Victory Stele (Credit: Wikipedia)
Section of Stele mentioning Israel (Credit: Bible Probe)

Based on this stele Humphreys and Waddington have concluded that Merneptah’s first year as Pharaoh was either 1210BC or 1209BC. As I first read their conclusion I didn’t see the connection to Joshua’s eclipse, Mernephat’s stele mentions Israel but says nothing about anything like an eclipse. Then I thought, are they assuming that Mernephat’s victory over Israel was also Joshua’s victory over the Amorites!!!

That’s way too much of an assumption for me! There is no evidence of any kind that Mernephat and Joshua fought each other or indeed existed at the same time, if Joshua existed at all. Assuming that the two stories of battles are about the same battle is just pure speculation.

I have decided to attempt to contact Doctors Humphreys and Waddington to ask for a little clarification, who knows maybe I missed something somewhere. I’ll let you know when and if I receive an answer.

If you’d like to read the original article ” Solar Eclipse of 1207BC helps to date Pharaohs” click on the link below.

https://academic.oup.com/astrogeo/article/58/5/5.39/4159289/Solar-eclipse-of-1207-BC-helps-to-date?guestAccessKey=96454415-36e7-4640-9fde-d942f3ad00b4

UPDATE: I received a reply from Sir Colin Humphreys, one of the authors of the article. (I didn’t know he was a Sir! The Queen’s birthday honours list of 2010 according to Wikipedia.)

Anyway, Sir Colin accepts that the battles fought by Joshua and Merneptah were not the same but he does believe that the two campaigns were near enough in time to allow him to use Joshua’s Miracle (The Eclipse of 1207BCE) to more accurately date Merneptah’s reign as Pharaoh.

I can only say once again that I am reluctant to accept the bible that literally. Or Merneptah for that matter, remember his stele states that “Israel is laid waste, his seed is not”. Well that’s a boast that rings pretty hollow. And Merneptah’s stele is contemporary with his campaign while the book of Joshua is considered to have been written 500 years later!

Paleontology News for October 2017.

The science of paleontology has been a very active and exciting field of research over the past few years and this past month has seen the announcement of several new discoveries. I’ve chosen three items to discuss in today’s post.

The first discovery I’d like to discuss concerns new evidence about the appearance and skin colouration of dinosaurs. Now everybody knows that most of the dinosaur fossils that are found are just the bones of the animals. And you certainly can’t tell what colour a creature was from its bones. Impressions of the skin of dinosaurs are rare and those impressions with traces of skin colour rarer still.

Because of this fact for many years dinosaurs were usually portrayed as having rather bland colouration, normally just a shade of green. The illustration below from Sinclair Oil Company (Their symbol is an Apatasaurus) shows what we thought dinosaurs looked like in the 1950s and 60s. Notice how the animals are all green or gray and even on those with strips the strips are just a different shade of the main colour.

Dinosaur Colouration as imagined in the 1950s (Credit: Sinclair Oil, Matthew Kalmenoff)

Scientists are a patient bunch however, they kept looking for evidence of soft tissue and there are a lot of fossils out there to find. Over the last twenty years a number of fossil specimens have been found that now tell us a great deal about dinosaur appearance. It turns out that some dinosaurs at least had either vibrant colours or elaborate patterns, or both on their skins, or feathers! Yes, we also now know that many dinosaurs were covered in feathers to keep them warm.

In fact a recent paper published in the journal ‘Current Biology’ describes how small theropod dinosaur from China called Sinosauropteryx, in addition to being feathered was also decked out in alternating dark and light bands similar to the way a raccoon looks. The image below shows what the animal looked like according to co-author Fiann Smithwick of Bristol University.

Drawing of Sinosauropteryx (Credit: Robert Nicholls)

Doctor Smithwick and his colleagues came to their conclusions after an extensive study of three excellently preserved specimens of Sinosauropteryx. The specimens were not only examined under a microscope but the researchers also used cross-polarized filters to bring out the contrast in the colour patters. The image below shows one of the fossils used in the study as seen under cross-polarized light, the areas of light and dark pigmentation are evident.

Sinosauropteryx Fossil (Credit: Jacob Vinther)

This pattern of colouration is known as counter shading and is a common pattern in living animals. Doctor Smithwick suggests that the dark patches around the eyes may have served to reduce glare the same way that athletes today paint a dark stripe under their eyes.

The second news item I’d like to discuss is about the discovery of two-foot long footprints of a predatory dinosaur from Lesotho in southern Africa. While not as large as Tyrannosaurus Rex the theropod that made the footprints came from a much earlier time, the beginning of the Jurassic period about 100 million years before T rex.

According to paleontologist Fabien Knoll of the University of Manchester “Our finding corroborates the hypothesis that theropods reached a great size relatively early in the course of their evolution, but apparently not before the Triassic-Jurassic boundary.” Despite the fact that no remains of the animal have been found so far it is estimated to have been about 10 meters in length and has been given the name Kayentapus ambrokholohali. The picture below shows the footprints of Kayentapus ambrokholohali.

Footprints of Kayentapus ambrokhlolhali (Credit: Reuters)

Finally, we don’t often hear about fossil discoveries from India so the discovery of a well preserved specimen of an ichthyosaur certainly deserves a quick mention. For those who don’t know ichthyosaurs were reptile versions of dolphins that lived during the time of the dinosaurs. Returning to the sea their ancestors had left behind these air breathing lizards evolved fins in place of legs and a fish like tail. The image below shows a typical ichthyosaur.

Ichthyosaur Illustration (Credit: Sedgwick Museum)

The specimen was discovered near the Indian city of Kutch in the province of Gujarat. According to Guntupalli Prasad of the University of Delhi the 5.5 meter fossil is believed to belong to the ichthyosaur family Ophthalmosauridae and lived between 90 and 165 million years ago. The photo below shows the ichthyosaur fossil as it was being unearthed.

Fossil Ichthyosaur in India (Credit: The Hindu)

With these and other exciting fossil finds coming to light on a regular basis this is obviously a good time to be a paleontologist.

Gravity Wave Detection on 17Aug17 quickly becomes the most thoroughly studied Astronomical Event ever.

The past week has been quite an exciting one for astronomy and the scientific community in general. We already knew a part of the story; indeed I mentioned it in a previous post (7Oct17). As a reminder, back on the 17th of August this year the LIGO gravity wave observatories in Hertford Oregon and Livingston Louisiana along with the new Virgo detector in Italy announced that they had made the third ever detection of gravity waves. We now know however, that was just the start of the story.

You see, even as the detectors at LIGO and Virgo were gathering their measurements, in orbit above the Earth the Fermi Gamma Ray Space Telescope was also busy detecting a Gamma Ray Burst, a short sharp pulse of gamma rays that occurs about once a day somewhere in the Universe. Gamma ray bursts are known to be amongst the powerful events ever seen.

Could these two completely different instruments have detected the same event, and if so could other astronomers with other telescopes also observe the event?

Boy did they. Within literally seconds emails were being sent out to astronomers around the world giving the approximate location of the event, a small region in the constellation of Hydra. As quickly as possible other astronomers were using their instruments see what they could find.

It was the Swope telescope at Cerro Las Campanas observatory in Chile that succeeded in finding the exact location, inside the galaxy NGC 4993 at a distance of about 130 million light years. Within hours four more telescopes were also making observations and by the next day the Chandra X-ray Space telescope, the Swift Ultra Violet Space telescope along with the Very Large Array Radio telescope in New Mexico had joined in.

The image below is the event as seen by the Dark Energy Camera at the Cerro Tololo Interamerican Observatory, also in Chile. The picture on the right shows the area of the sky before the event while the picture on the left shows a tiny new dot above the bright object in the center. That small dot is the source of the gravity waves and gamma ray burst.

Source of Gravity Waves (Credit: National Optical Astronomy Observatory)

The event, which has been given the names GW170817 for the gravity wave observation and GRB170817A for the gamma ray burst, has become one of the most studied phenomenons in the history of science. A compendium paper of all of the observations has been submitted to ‘The Astrophysics Journal’ with 4,500 listed authors from 910 institutions. That’s about one third of all professional astronomers in the world.

So what was the event, and what did we learn for it. First of all the observations are consistent with our theories about the merger of two neutron stars into either a larger neutron star or more likely a black hole. And as for what we learned, it’s a little too soon to tell but the fact that our theories were so close indicates that we are making great progress in our understanding of some of the rarest and most powerful events in the Universe. The image below shows an artist’s representation of a neutron star merger.

Artist’s View o9f Neutron Star Merger (Credit: Robin Dienel, Carnegie Institute for Science)

In some ways however, the most impressive thing about the observations of 17August is that the new gravity wave detectors have now been integrated into an ever growing network of astronomical observatories. This network has been developed over the last ten years or so and uses the Internet to maintain instantaneous cooperation between some of the most advanced instruments ever developed. In this way astronomers around the world are ready at a moment’s notice to swing into action to study the most powerful and transient events in the Universe.

All of the papers written thus far have been from observing astronomers; the theoreticians haven’t had the time to study the data. When they do they’ll refine their models and make new predictions. Based on those predictions the observatories will have a better idea of what to look for the next time.

This is how we progress, getting closer to the truth with each event we study. The gravity wave observatories are a new way of looking at the Universe and so far it appears that we’re going to be learning a lot from them.

 

Star Talk for 15Oct17. Neil deGrasse Tyson’s interview with Jane Goodall.

Last night on Star Talk, seen Sundays on the National Geographic channel, host Neil deGrasse Tyson had a very interesting and important interview with Jane Goodall, the noted anthropologist and one of the most influential scientists of the last fifty years. Doctor Goodall is of course best known for her intimate studies of Chimpanzee behaviour, studies that have taught us as much about ourselves as our closest relatives.

Neil began the interview by asking Dame Jane, she has been knighted by Queen Elizabeth, how she first got interested in science. Goodall’s answer was rather typical of many scientists. From her earliest days she remembers liking animals and when she was four she and her family visited a relative’s farm where she was given the job of collecting eggs.

After asking the adults where the hole was that the eggs came from, and being given an unsatisfactory answer, Jane proceeded to follow a hen into the henhouse and watched her for four hours. She was gone for so long that her family thought she was lost, the police were even called. Still, she found out where the eggs came from. The image below shows Neil with Jane Goodall.

Jane Goodall with Neil deGrasse Tyson (Credit: Star Talk, National Geographic Channel)

Every time I’ve seen Jane Goodall interviewed she never fails to mention her mentor the paleoanthropologist Louis Leakey, the man whose discoveries at Olduvai Gorge in what is now the nation of Tanzania gave us the first evidence for the earliest tool using hominids.

In the early 1960s Leakey had learned much about the physiology and tool making abilities of those hominids but “behaviour doesn’t fossilize” and he realized that the best way to understand the behaviour of our ancestors would be to study our closest relatives the Chimpanzees.

Leakey reasoned that any common behaviour shared between ourselves and chimps would probably also be shared with our ancestors. The person he choose for the job was Jane Goodall, who didn’t even have a bachelor’s degree at the time, but she liked animals.

Goodall spent the next five years at Gombe Stream National Park in Tanzania revolutionizing the field of animal research by almost becoming a member of a group of Chimpanzees. Her biggest discovery in those years was the tool making ability of chimps, behaviour that at that times was believed only humans possessed. The image below shows the first photograph of a Chimpanzee using a tool it had made for catching termites from a mound.

First Photograph of a Chimpanzee using a Tool (Credit: Star Talk, National Geographic Channel)

Goodall then returned the UK to get her doctorate, her thesis was ‘The Behaviour of Free Living Chimpanzees’. After receiving her degree Goodall returned to Gombe and spent over thirty years studying the Chimpanzees there. She made many more discoveries, such as the fact that chimpanzees hunt; by cooperating they’re actually successful more often than lions are.

Goodall also saw the dark side of chimp behaviour, murder, rape and even war between different groups. Jane Goodall certainly fulfilled Louis Leakey’s desire to learn about the behaviours we share with the chimpanzees.

As always Neil deGrasse Tyson was joined by a couple of guests in the studio at the Hayden planetarium. One was the comic Chuck Nice, a frequent guest who always succeeds in bringing a few laughs to the discussion. The other guest was Anthropologist Jill Pruetz who had clearly been inspired by Jane Goodall in her early life. Doctor Pruetz, who is studying Chimpanzees in Senegal, discussed one aspect of chimp behaviour that even Doctor Goodall missed; Culture!

You see Doctor Goodall spent her career studying a single chimpanzee group in a small area. It wasn’t until other researchers like Doctor Pruetz studied chimps in other parts of Africa that Chimpanzee culture became evident. The evidence of different types of tool use, different styles of nest building and other behaviours, even differences in vocal calls (Language!!!) Show that chimps in different regions have differences that can only be described as cultural. Yet another way that chimpanzees resemble us.

Jane Goodall’s legacy lays in illustrating humanity’s true place in the World, in showing us how we are not as different as we’d like to think we are. The show Star Talk continues to be a place where scientists like Jane Goodall, and their discoveries can be discussed.

 

 

Space New for October 2017.

Space X is once again heading our space news for the month. On October 11th the privately owned space corporation successfully reused one of its Falcon 9 first stage booster rockets for the third time . The rocket that put the Echo Star 105/SES-11 satellite into orbit had been used previously back on February the 19th to launch Space X’s Dragon resupply capsule on a mission to the International Space Station.

That launch back in February had been Space X’s first launch from NASA’s historic pad 39A, the same pad that had seen so many of the Apollo and Space Shuttle take offs. This was also Space X’s second successful launch in three days demonstrating the company’s increasing skill and competence in the task of launching payloads into space. The image below shows the liftoff of Space X’s Falcon 9.

Launch of Space X’s Falcon 9 (Credit: Space X)

Both of the first stages used in this week’s missions landed intact on Space X’s recovery barge. In fact Space X has now recovered their first stage boosters 18 times making the feat seem almost routine. By making both the recovery and reuse of their boosters routine Space X hopes to reduce the cost of getting into space, dollars per kilo to orbit, enough to greatly increase the amount of cargo going into space. This is something business types call ‘Economies of Scale’ which will help to drive down the cost of space travel even further.

One last word about Space X. Next year the company, along with their rival Boeing, is scheduled to begin test flights of their manned orbital capsules. According to NASA’s commercial crew program each company will perform one unmanned test flight to be followed by a manned flight late next year. Those flights will be the first time in seven years that astronauts will fly into orbit from American soil.

Another space event that got a bit of news play involved the close approach by the asteroid 2012 TC4. The asteroid, which is estimated to be about 30 meters across, came within 43,000 kilometers of Earth on the night of 12 October. Now 43,000 km may sound like a long way off but in terms of the solar system it’s a near miss. It is in fact only a little more than a tenth of the distance to the Moon. The image below shows a NASA illustration of what 2012 TC4 looked like as it passed by Earth.

Illustration of Asteroid 2012TC4 passing Earth (Credit: NASA)

In fact since 2012 TC4 was coming so close NASA decided to use the encounter as the first test of their ‘Planetary Defense System’. A system which one day may be used to deflect, or if necessary destroy, an asteroid on a collision course with our planet.

This initial test simply used NASA’s network of observatories to keep a closer watch on the asteroid’s trajectory as it went by. In 2024 however, NASA hopes to arrange a mission to actually alter the course of an asteroid. Not one on a collision course but another close encounter like 2012 TC4.

The mission is being called DART and the target is actually a pair of asteroids called Didymos that are bound together by their mutual gravity. The test will involve slamming a space probe into the smaller (~150m) asteroid in order to see how its orbit around its larger (800m) companion is effected. From the results of the experiment NASA hopes to learn just how much push would be needed to alter an asteroid’s course enough to prevent a collision in the future. The long term goal would be protect the Earth from disasters such as the one that killed off the dinosaurs.

One final item before I leave. Last month (13Sept17) I wrote a post about the final days of NASA’s Cassini spacecraft before it plunged into the atmosphere of the planet Saturn. Now the Jet Propulsion Labouratory (JPL) and NASA have released some of the details of the doomed space probe’s final minutes. According to JPL Cassini ‘put up a fight’ and fired it thrusters for 91 seconds trying desperately to keep its antenna pointed toward Earth and transmitted data until the last second.

By greatly exceeding its designer’s expectations it’s as if Cassini had acquired something of a personality, a determination to carry out its mission to the end. And it’s not just Cassini. The Voyager probes are still sending us information on interstellar space after more than 40 years and the Lost Horizon spacecraft is now preparing for a flyby of a Kuiper belt object. It’s almost as if these interplanetary explorers are becoming the first mechanical heroes.

Oh I know that’s kind of silly. Or is it, after all who knows what our space probes will be like a hundred years from now. Cassini’s final image, transmitted to Earth even as the probe was falling into Saturn’s atmosphere is below.

Cassini’s Final image (Credit: NASA-JPL)

 

 

 

 

The Highest Energy Cosmic Rays come from outside our Galaxy, and just what are Cosmic rays anyway?

Even after more than a hundred years of study the origin and to a lesser extent the nature of Cosmic Rays is still something of a mystery. It was in 1912 that Victor Hess used a balloon to sent three electrometers, an early device for measuring radiation, to an altitude of 5300 meters. His discovery that the intensity of radiation increased as you ascended into the atmosphere stunned scientists. For his discovery Hess would be awarded the Nobel Prize in Physics in 1936.

It was quickly realized that the radiation being detected by Hess and others was actually the secondary products of collisions taking place in the upper reaches of our atmosphere between atoms of gas and some very powerful sources of energy coming from outer space. At first scientists believed that the primary component of the radiation was some form of X-ray or Gamma Ray, hence the name Cosmic Rays. It wasn’t until 1927 that physicist Jacob Clay was able to demonstrate that the source of Cosmic Rays was affected by the Earth’s magnetic field and therefore had to consist of charged particles.

In the years that followed physicists slowly learned that most (~90%) of cosmic ray showers are produced when a proton, with velocity nearly that of light slams into an atom in the air, shattering the atom and producing a spray of particles. In very energetic events the secondary particles produced by the initial collision may still have enough energy to strike and shatter further atoms leading to a cascade of sub-atomic particles. The diagram below illustrates such a cascade.

Primary cosmic ray. Development of an extensive air. shower in the Earth’s. atmosphere. Mostly muons, electrons and photons at Earth’s surface. (Credit: Pierre Auger)

Now I said that 90% of the primary particles are simple protons but about 9% have been found to be the nuclei of Helium atoms (two protons and two neutrons). The last 1% is composed of the nuclei of all the known atoms up to and including Uranium. In many ways the primary Cosmic Rays look just like the nuclei of the elements that the Sun is made of, accelerated to nearly the speed of light.

That resemblance to the composition of Stars gives us a clue as to where the Cosmic Rays get their energy. Our best model for the generation of Cosmic Rays uses the powerful explosions known as Supernova to boost some atoms to incredible energies. However calculations show that even Supernova are not powerful enough to produce the most energetic Cosmic Rays. Over the last 30 years astrophysicists have added black holes to the list of possible Cosmic Ray factories but not even black holes can account for some of the most energetic Cosmic rays that have been observed. Where these Ultra High Energy Cosmic Rays (UHECR) come from is still a hot question in astrophysics. The Cosmic Ray spectrum, that is the number of incident particles as a function of energy, is shown in the diagram below.

Cosmic Ray Flux. Number of Particles vs. Energy (Credit: Sven Lafebre)

It should be mentioned at this point that some of the Cosmic Ray particles that have been observed are millions of times more energetic than the particles accelerated in the Large Hadron Collider (LHC) at CERN. Now the LHC is the most powerful particle accelerator humanity has ever built, accelerating protons to an energy of 13 Trillion electron volts. That amount of energy would be about in the middle of the diagram above. Therefore all of the Cosmic Rays on the right hand side of the diagram are more powerful than anything humanity has ever produced. It’s easy to understand why physicists are so curious about where their energy comes from.

The Ultra High Energy Cosmic Rays (UHECR) are being studied by the Pierre Auger experiment, a vast array of detectors spread out over 3,000 square kilometers of the grasslands of Argentina. Since the more powerful the initial Cosmic Ray particle the larger the cascade it produces at Earth’s surface the Pierre Auger experiment must be physically large in order to capture the largest, most energetic cascades.

Recently the scientists at Pierre Auger have published a paper in which they announce that the very highest energy Cosmic Rays, those more than a million times the energy of the LHC, come from outside our Galaxy. This result comes from the study of 30,000 such particles. This is only one more clue in our attempts to unravel the mystery of Cosmic Rays but we have already learned much in the last century. If you’d like to learn more about Cosmic Rays or the Pierre Auger experiment click on the link below to be taken to the Pierre Auger website.

https://www.auger.org/