This is an illustration to explain the dynamics of the ultra-relativistic third Van Allen radiation belt. Credit: Andy Kale
The dynamic relationship between Earth and the Sun two sides. The warmth from the Sun makes life on Earth possible, but the rest of the Sun’s intense energy pummels the Earth, and could destroy all life, given the chance. But thanks to our magnetosphere, we are safe.
The magnetosphere is our protective shield. It’s created by the rotation of the molten outer core of the Earth, composed largely of iron and nickel. It absorbs and deflects plasma from the solar wind. The interactions between the magnetosphere and the solar wind are what create the beautiful auroras at Earth’s poles.
Visualization of the solar wind encountering Earth’s magnetic “defenses” known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet’s nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPL
In the inner regions of Earth’s magnetosphere are the Van Allen belts, named after their discoverer James Van Allen. They consist of charged particles, mostly from the Sun, and are held in place by the magnetosphere. Usually, there are two such belts.
The Van Allen radiation belts surrounding Earth. Image: NASA
But the output from the Sun is not stable. There are periods of intense energy output from the Sun, and when that happens, a third, transient belt can be created. Up until now, the nature of this third belt has been a puzzle. New research from the University of Alberta has shown how this phenomena can happen.
Researchers have shown how a so-called “space tsunami” can create this third belt. Intense ultra-low frequency plasma waves can transport the outer part of the radiation belt into interplanetary space, and create the third, transient belt.
The lead author for this study is physics professor Ian Mann from the University of Alberta, and former Canada Research Chair in Space Physics. “Remarkably, we observed huge plasma waves,” said Mann. “Rather like a space tsunami, they slosh the radiation belts around and very rapidly wash away the outer part of the belt, explaining the structure of the enigmatic third radiation belt.”
This new research also sheds light on how these “tsunamis” help reduce the threat of radiation to satellites during other space storms. “Space radiation poses a threat to the operation of the satellite infrastructure upon which our twenty-first century technological society relies,” adds Mann. “Understanding how such radiation is energized and lost is one of the biggest challenges for space research.”
It’s not just satellites that are at risk of radiation though. When solar wind is most active, it can create extremely energetic space storms. They in turn create intense radiation in the Van Allen belts, which drive electrical currents that could damage our power grids here on Earth. These types of storms have the potential to cause trillions of dollars worth of damage.
A better understanding of this space radiation, and an ability to forecast it, are turning out to be very important to our satellite operations, and to our exploration of space.
The Van Allen belts were discovered in 1958, and classified into an inner and an outer belt.
The Van Allen Belts around Earth. The inner red belt is mostly protons, and the outer blue belt is mostly electrons. Image Credit: NASA
In 2013, probes reported a third belt which had never before been seen. It lasted a few weeks, then vanished, and its cause was not known. Thanks to Mann and his team, we now know what was behind that third belt.
“We have discovered a very elegant explanation for the dynamics of the third belt,” says Mann. “Our results show a remarkable simplicity in belt response once the dominant processes are accurately specified.”
An understanding of the radiation in and around Earth and the Van Allen belts is of growing importance to us, as we expand our presence in space. Our technological society relies increasingly on satellite communications, and on GPS satellites. Radiation in the form of high-energy electrons can wreak havoc on satellites. In fact, this type of radiation is sometimes referred to as a satellite killer. Satellites require robust design to be protected from them.
Organizations like the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and the International Living with a Star (ILWS) Program are attempts to address the threat that radiation poses to our system of satellites.
Osterplana 65, the meteorite at the heart of a mystery. This meteorite is different than the thousands of other meteorites in collections around the world. Image: Birger Schmitz
470 million years ago, somewhere in our Solar System, there was an enormous collision between two asteroids. We know this because of the rain of meteorites that struck Earth at that time. But inside that rain of meteorites, which were all of the same type, there is a mystery: an oddball, different from the rest. And that oddball could tell us something about how rocks from space can change ecosystems, and allow species to thrive.
This oddball meteorite has a name: Osterplana 65. It’s a fossilized meteorite, and it was found in a limestone quarry in Sweden. Osterplana 65 fell to Earth some 470 mya, during the Ordovician period, and sank to the bottom of the ocean. There, it became sequestered in a bed of limestone, itself created by the sea-life of the time.
The Ordovician period is marked by a couple thing: a flourishing of life similar to the Cambrian period that preceded it, and a shower of meteors called the Ordovician meteor event. There is ample evidence of the Ordovician meteor event in the form of meteorites, and they all conform to similar chemistry and structure. So it’s long been understood that they all came from the same parent body.
The collision that caused this rain of meteorites had to have two components, two parent bodies, and Osterplana 65 is evidence that one of these parent bodies was different. In fact, Ost 65 represents a so far unknown type of meteorite.
The faint grey lines in this electron image of Ost 65 are called “shock deformation lamellae” and they are evidence that Ost 65 was the result of a collision. Image: B. Schmidt
The study that reported this finding was published in Nature on June 14 2016. As the text of the study says, “Although single random meteorites are possible, one has to consider that Öst 65 represents on the order of one per cent of the meteorites that have been found on the mid-Ordovician sea floor. “It goes on to say, “…Öst 65 may represent one of the dominant types of meteorites arriving on Earth 470 Myr ago.”
The discovery of a type of meteorite falling on Earth 470 mya, and no longer falling in our times, is important for a couple reasons. The asteroid that produced it is probably no longer around, and there is no other source for meteorites like Ost 65 today.
The fossil record of a type of meteorite no longer in existence may help us unravel the story of our Solar System. The asteroid belt itself is an ongoing evolution of collision and destruction. It seems reasonable that some types of asteroids that were present in the earlier Solar System are no longer present, and Ost 65 provides evidence that that is true, in at least one case.
Ost 65 shows us that the diversity in the population of meteorites was greater in the past than it is today. And Ost 65 only takes us back 470 mya. Was the population even more diverse even longer ago?
The Earth is largely a conglomeration of space rocks, and we know that there are no remnants of these Earthly building blocks in our collections of meteorites today. What Ost 65 helps prove is that the nature of space rock has changed over time, and the types of rock that came together to form Earth are no longer present in space.
Ost 65 was found in amongst about 100 other meteorites, which were all of the same type. It was found in the garbage dump part of the quarry. It’s presence is a blemish on the floor tiles that are cut at the quarry. Study co-author Birgen Schmitz told the BBC in an interview that “It used to be that they threw away the floor tiles that had ugly black dots in them. The very first fossil meteorite we found was in one of their dumps.”
According to Schmitz, he and his colleagues have asked the quarry to keep an eye out for these types of defects in rocks, in case more of them are fossilized meteorites.
Finding more fossilized meteorites could help answer another question that goes along with the discovery of Ost 65. Did the types and amounts of space rock falling to Earth at different times help shape the evolution of life on Earth? If Ost 65 was a dominant type of meteorite falling to Earth 470 mya, what effect did it have? There appear to be a confounding number of variables that have to be aligned in order for life to appear and flourish. A shower of minerals from space at the right time could very well be one of them.
Whether that question ever gets answered is anybody’s guess at this point. But Ost 65 does tell us one thing for certain. As the text of the study says, “Apparently there is potential to reconstruct important aspects of solar-system history by looking down in Earth’s sediments, in addition to looking up at the skies.”
'Northern Lights above Lofoten,' a photo taken by Alex Conu, won first prize in the 'Against the Lights' category in the 2016 International Earth & Sky Photo Contest. The image was taken from a mountaintop in Lofoten Islands, Norway. Credit and copyright: Alex Conu.
The winners of the 7th annual Earth & Sky Photo Contest have been announced, and wow, these images are absolutely stunning! The contest really highlights the beauty of the night sky, and its mission is to spread the message to cut down on light pollution while helping to preserve the last remaining natural night environments and night skies in the world. The contest was organized by The World at Night (TWAN) and other sister organizations.
“The sky above us is an essential part of our nature, a heritage for us and other species on this planet,” said TWAN founder and contest chair, Babak Tafreshi.”The contest main goal is to present the night sky in this broader context that helps preserving the natural night sky by reconnect it with our modern life.”
See more winning photos below:
The second place winner in the ‘Against the Light’ category is Carlo Zanandrea from Italy for “All that Glitters is not Gold” taken in December 2015 showing constellation Orion rising over lights and fog in the province of Treviso in northeastern Italy. Credit and copyright: Carlo Zanandrea.
Just last week, a group of Italian and American scientists unveiled a new global atlas of light pollution, and sadly, they said the results show the Milky Way is “but a faded memory to one-third of humanity and 80 percent of Americans.”
“We’ve got whole generations of people in the United States who have never seen the Milky Way,” said Chris Elvidge, a scientist with NOAA’s National Centers for Environmental Information. “It’s a big part of our connection to the cosmos — and it’s been lost.”
These photos from Earth & Sky Contest really display that important connection, with people and places on Earth being a big part of many of the images – the classic definition of “TWAN-style” photography. According to the contest theme of “Dark Skies Importance,” the submitted photos were judged in two categories: “Beauty of The Night Sky” and “Against the Lights.”
“The selected images are those most effective in impressing public on both how important and delicate the starry sky is as an affecting part of our nature, and also how bad the problem of light pollution has become,” TWAN said in their press release. “Today, most city skies are virtually devoid of stars. Light pollution (excessive light that scatters to the sky instead of illuminating the ground) not only is a major waste of energy, it also obscures the stars, disrupts ecosystems and has adverse health effects.”
“The Photographer” by Nicholas Roemmelt from Austria is the second place winner in the ‘Beauty of the Night Sky category, taken in March 2015 in Stockiness, Iceland. Credit and copyright: Nicholas Roemmelt
The winning images were chosen on their “aesthetic merit and technical excellence,” said David Malin of the judging panel, who is well-known pioneer in scientific astrophotography. “We believe they accurately reflect the state of the art in TWAN-style photography. The competition encourages photographers with imagination to push their cameras to their technical limits, and to produce eye-catching images that appear perfectly natural and are aesthetically pleasing.”
This photo, “Viking Lights” by Adam Woodworth from USA, won in the composite section of the ‘Beauty of the Night Sky’ category, where frames of various exposure or focus settings are blended. This image was captured in Newfoundland, Canada in June, 2015. Credit and copyright: Adam Woodworth.In the photo sequence submissions, the winner in the Beauty category is “Total Solar Eclipse from Svalbard” by Thanakrit Santikunaporn from Thailand. He captured the eclipse phases every 3 minutes over frozen landscape of Svalbard, Norway on March 20, 2015. Credit and copyright: Thanakrit Santikunaporn.
The contest was open to anyone of any age, anywhere in the world; to both professional and amateur/hobby photographers. It has been an annual event since 2009 (initially for the International Year of Astronomy) by TWAN, the National Optical Astronomy Observatory, and Global Astronomy Month from Astronomers Without Borders. The contest supports efforts of the International Dark Sky Association (IDA) and other organizations that seek to preserve the night sky.
The images were taken in 57 countries and territories including Algeria, Antarctica, Australia, Austria, Bahamas, Belgium, Bolivia, Brazil, Canada, China, Colombia, Croatia, Czech Republic, Egypt, England, Estonia, Finland, France, Germany, Greece, Guatemala, Guam, Hungary, Iceland, India, Indonesia, Iran, Ireland, Italy, Japan, Jordan, Kenya, Lithuania, Madagascar, Malaysia, Malta, Morocco, Norway, New Zealand, Paraguay, Peru, Philippines, Poland, Reunion (France), Romania, Russia, Scotland, Sri Lanka, South Africa, Spain, South Africa, Sri Lanka, Sweden, Switzerland, Tanzania, Thailand, Ukraine, and USA.
See all the images and more information about them at TWAN. Click on each image for larger versions. A larger version of the lead image can be found here.
You can see the global atlas of light pollution here, which was created from data from the NOAA/NASA Suomi National Polar-orbiting Partnership satellite and calibrated by thousands of ground observations.
And here’s a video that includes all the winning images:
It’s an apocryphal image. The ignorant faces of the dinosaurs, roaring helplessly at their fate, and looking skyward as an asteroid plunged to Earth. And the sneaky, clever little mammals coming out of their hiding holes to take their rightful place. If you grew up reading about this version of things, you’re not alone.
The line of reasoning says that mammals were present during the dinosaur’s reign, but their potential to thrive was suppressed by the dinosaurs, which were supremely evolved to dominate conditions on Earth at the time. It took the extinction of the dinosaurs to allow mammals to flourish. But according to new studies, that might not have been the case. As it turns out, mammals may have been well on their way to displacing the dinos long before the Chicxulub meteor hastened the dinosaur’s demise.
One such study, from researchers at the Universities of Southampton and Chicago, focused on hundreds of fossilized mammal teeth. As you know if you’ve been paying attention to how you eat, different teeth have different purposes. Carnivores have sharp teeth designed to rip and shred flesh, while herbivores have duller teeth for grinding up vegetation. Omnivores, like us, have a bit of both. That’s a simplification, of course, but its generally true.
What this study showed is that mammals with varied diets began to appear 10 to 20 million years before the dinosaurs were extinguished. It focused on early therian mammals, which are the ones that gave rise to the modern marsupials (ones with pouches) and placentals (ones where a fetus is carried inside the uterus). The third class of mammal, monotremes, were egg-laying mammals like the platypus.
In recent years, more and more early mammal fossils have been discovered, and they show that mammals were well on their way to diversifying long before the dinosaurs disappeared. The mammal fossil record also shows that mammal diversity suffered from the meteor strike, but mammals recovered and diversified into a greater number of species in the new conditions.
Another study, by Manabu Sakamoto and Chris Venditti from the University of Reading, and by Michael Benton from the University of Briston, shows that the opposite is true for dinosaurs. For tens of millions of years before their extinction, dinosaur species were becoming extinct and new species were not taking their place. This made the dinosaurs more vulnerable to extinction, whereas the diversifying mammals were in a better position to thrive, regardless of dinosaur extinction.
The main threat posed by the asteroid strike was the climate change that followed it. With greater species diversity in place immediately preceding the strike, mammals had a greater probability to survive the changing climate than did their dinosaur counterparts.
Evolutionary biologist and co-author of the study, Dr. Chris Venditti, told BBC News, “The current widespread view is that dinosaurs were reigning strong right up to the impact that hit the Earth – and it’s the impact that drove their final extinction,” he said. “And while that’s certainly true, what we found was that they were on the decline long before that.”
This image shows a very faint circular outline of the Chicxulub crater, site of the asteroid strike that finished off the dinosaurs. After 65 million years, it is barely visible. Image: NASA/JPL
“If they were reigning strong perhaps they would have fared much better than they did,” said Venditti. Dinosaurs had been around for 160 million years and had faced pressures and had dips in their diversity before.
This begs the question, why were dinosaurs in decline?
It likely all revolves around the environmental conditions. At the dawn of the dinosaurs 230 million years ago, Earth was a warm, lush place. Not just near the equators, but all the way to the poles. And there was one single continent, called Pangaea. But it’s the nature of things to change, and change it did.
The climate cooled, the sea level changed, and the dinosaurs were facing new environmental pressures. And as the record shows, the dinosaurs were losing species faster than they could replace them. Chicxulub was more than they could recover from.
Study co-author Mike Benton also talked to the BBC about this study. He said, “World climates were getting cooler all the time. Dinosaurs rely on quite warm climates and mammals are better adapted to the cold.”
“So there might have been a switch over in any case without the asteroid impact.”
Looking back on the older narrative, that the asteroid strike wiped out the dinosaurs, and mammals took their place and became dominant, it looks a little simplistic. But it has a nice narrative hook, and there is the matter of the cataclysmic asteroid strike, which no doubt had a huge effect on life on Earth, any way you want to slice it.
It’s possible that had the asteroid not struck, or had struck a few million years earlier or later, Earth would be a much different place. Perhaps we would not be here, and maybe intelligent dinosaurs would be in our place.
We’ll never know, of course, but it’s a fun narrative.
Mars Close Approach over recovered SpaceX Falcon 9 atop droneship at sea on June 1, 2016 as seen from Jetty Park Pier in Port Canaveral, FL. Credit: Ken Kremer/kenkremer.com
Mars Close Approach over recovered SpaceX Falcon 9 atop droneship at sea on June 1, 2016 as seen from Jetty Park Pier in Port Canaveral, FL. Credit: Ken Kremer/kenkremer.com
PORT CANAVERAL, FL – As you may have heard its Mars opposition season. What you may not have heard is that Mars made its closest Earth approach high in the Sunshine states nighttime skies coincidentally at the same time as a sea landed SpaceX Falcon 9 was visible just offshore floating on the horizon below.
Rather miraculously this regular natural occurrence of the dance of the planets Earth and Mars making a close embrace as they orbit around our Sun, was taking place simultaneously with a most unnatural event – namely the return of a used SpaceX Falcon 9 landed on a platform at sea that was briefly hugging the Florida coastline.
And better yet you can see them celebrating this first-of-its-kind celestial event together in the photo above of ‘Mars Close Approach over Falcon’ – captured by this author around 11 p.m. EDT on Wednesday, June 1 from the rock wall along Jetty Park Pier in Port Canaveral, Fl.
By sheer coincidence, the Red Planet was making its closest approach to Earth of this orbital cycle just as the most recently launched and recovered SpaceX Falcon 9 first stage booster was arriving just offshore of Cocoa Beach and the Florida Space Coast earlier this week.
As luck would have it, when I ventured out to watch the boosters hoped for nighttime arrival from Jetty Park Pier in Port Canaveral on Wednesday, June 1, I noticed that Mars and the floating Falcon 9 were lined up almost perfectly.
Mars is visible at the head of the large constellation Scorpius.
The Falcon 9 was standing atop the droneship upon which it had landed on May 27 while it was stationed approximately 420 miles (680 kilometers) off shore and east of Cape Canaveral, Florida, surrounded by the vastness of the Atlantic Ocean.
The SpaceX Falcon 9 began its rapid journey to space and back roaring to life at 5:39 p.m. EDT last Friday, May 27, from Space Launch Complex-40 at Cape Canaveral Air Force Station, FL, ascending into sky blue sunshine state skies.
The Falcon 9 was carrying the Thaicom-8 telecommunications satellite to orbit.
On Wednesday night, June 1, Mars was high in the southern night sky, shining brightly almost directly over the spent Falcon 9 booster sailing some 3 miles (5 km) offshore of Cocoa Beach.
Thankfully the weather gods even cooperated by delivering crystal clear nighttime skies.
So with Mars at Opposition and Falcon 9 in view and while awaiting the droneship bringing the booster into Port Canaveral I took some exposure shots of this first totally unique opportunity.
Mars Close Approach took place on May 30, 2016. That is the point in Mars’ orbit when it comes closest to Earth.
The Red Planet was only 46.8 million miles (75.3 million kilometers) from Earth.
“Mars reaches its highest point around midnight — about 35 degrees above the southern horizon, or one third of the distance between the horizon and overhead,” according to a NASA description and the graphic shown below.
Mars closest approach to Earth this cycle is May 30, 2016. That is the point in Mars’ orbit when it comes closest to Earth. Mars will be at a distance of 46.8 million miles (75.3 million kilometers). Credit: NASA/JPL-Caltech
Mars is currently visible for much of the night.
Mars oppositions happen about every 26 months when Mars and the sun are on directly opposite sides of Earth.
The 156 foot tall Falcon 9 booster had landed atop the specially designed SpaceX ‘droneship’ named “Of Course I Still Love You” or “OCISLY” less than 9 minutes after the May 27 blastoff.
Incredible sight of pleasure craft zooming past SpaceX Falcon 9 booster from Thaicom-8 launch on May 27, 2016 as it arrives at the mouth of Port Canaveral, FL, atop droneship platform on June 2, 2016. Credit: Ken Kremer/kenkremer.com
But unlike the prior two sea landings, this booster came to rest at noticeable tilt.
This caused SpaceX some headaches and concern it might fall over and be destroyed in transit before reaching land.
So the booster didn’t make it back into port Wednesday night as onlookers had hoped. And SpaceX did not announce a return schedule.
It actually would up station keeping and hugging the shoreline for nearly 2 extra days while workers stabilized the booster.
Tow boat passing in front of the used SpaceX rocket waiting offshore. Credit: Julian Leek
The 15 story tall spent first stage was secured with multiple tie downs to the droneships deck.
Up close view of base of recovered SpaceX Falcon 9 atop droneship during arrival on June 2, 2016 shows ties down securing booster to deck. Credit: Ken Kremer/kenkremer.com
As I witnessed and reported here, the booster finally sailed triumphantly into the mouth of Port Canaveral around lunchtime on Thursday, June 2.
SpaceX Falcon 9 booster moving along the Port Canaveral channel atop droneship platform with cruise ship in background nears ground docking facility on June 2, 2016 following Thaicom-8 launch on May 27, 2016. Credit: Ken Kremer/kenkremer.com
Mars and the recovered Falcon 9 actually tie in rather neatly.
The SpaceX rockets launch and recovery technology are all being developed so they will one day lead to establishing a ‘City on Mars’ – according to the SpaceX’s visionary CEO and founder Elon Musk.
Musk aims to radically slash the cost of launching future rockets by recycling them and using them to launch new payloads for new paying customers.
Musk hopes to launch humans to Mars by the mid-2020s.
NASA’s Opportunity rover discovers a beautiful Martian dust devil moving across the floor of Endeavour crater as wheel tracks show robots path today exploring the steepest ever slopes of the 13 year long mission, in search of water altered minerals at Knudsen Ridge inside Marathon Valley on 1 April 2016. This navcam camera photo mosaic was assembled from raw images taken on Sol 4332 (1 April 2016) and colorized. Credit: NASA/JPL/Cornell/ Ken Kremer/kenkremer.com/Marco Di Lorenzo
Watch for Ken’s continuing on site reports direct from Cape Canaveral and the SpaceX launch pad.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Learn more about SpaceX Falcon 9 rocket, ULA Atlas rocket, Orbital ATK Cygnus, ISS, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events:
June 8/9: “SpaceX, ULA, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Upgraded SpaceX Falcon 9 blasts off with Thaicom-8 communications satellite on May 27, 2016 from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL. 1st stage booster landed safely at sea minutes later. Credit: Ken Kremer/kenkremer.com
Upgraded SpaceX Falcon 9 blasts off with Thaicom-8 communications satellite on May 27, 2016 from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL. 1st stage booster landed safely at sea minutes later. Credit: Ken Kremer/kenkremer.com
CAPE CANAVERAL AIR FORCE STATION, FL. – Atop a billowing plume of fire and smoke a SpaceX Falcon 9 rocket soared to space this afternoon, Friday, May 27, as the crackling thunder of the engines roared across the Florida space coast and the company scored a stunning double headed launch and landing success.
The 229 foot-tall (70 meter) Falcon 9 successfully delivered a 7000 pound commercial Thai telecommunications satellite to a Geostationary Transfer Orbit (GTO) and the first stage booster successfully soft landed on a platform at sea some nine minutes later.
Thus SpaceX is now an unfathomable 3 for 3 in the last three first stage landing attempts – both at sea and on land.
Even more remarkable is the string of two straight successes in landings via the high energy reentries as a consequence of launching the commercial payloads to GTO.
The Falcons screams were the loudest and most thrilling I’ve ever heard from a SpaceX launch as the two stage rocket lifted off on time at 5:39 p.m. EDT from Space Launch Complex-40 at Cape Canaveral Air Force Station, FL.
“Satellite deployed to 91,000 km apogee,” tweeted SpaceX CEO and founder Elon Musk.
“All looks good.”
Upgraded SpaceX Falcon 9 blasts off with Thaicom-8 communications satellite on May 27, 2016 from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL. 1st stage booster landed safely at sea minutes later. Credit: Ken Kremer/kenkremer.com
The spectacular looking launch into mostly sunny Florida skies followed a days delay forced by a technical glitch in the second stage.
SpaceX engineers had to lower the Falcon 9 to the horizontal position and hurriedly fix the second engine actuator that gave concerning readings during Thursday’s original launch attempt and scrubbed the liftoff – and do so in time to safely carry out a launch attempt late this afternoon.
Hundreds of millions of dollars were at stake on this commercial flight slated to deliver the Thaicom-8 comsat to a Geostationary Transfer Orbit (GTO) for Thaicom PLC, a leading satellite operator in Asia.
The first and second stages separated as planned about 2 minutes and 39 seconds after liftoff.
The nosecone, or payload fairing deployed into two halves at about T plus 3 minutes and 37 seconds.
Up close view of payload fairing of SpaceX Falcon 9 rocket delivering Thaicom-8 communications satellite on May 27, 2016 from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL. Credit: Ken Kremer/kenkremer.com
The second stage with Thaicom-8 continued to orbit. A pair of burns carried Thaicom-8 to orbit and the satellite was deployed at T plus 31 minutes and 56 seconds.
The rocket arced over as it accelerated eastwards towards Africa.
The nine first stage Marlin 1D engines on the 229 foot tall Falcon 9 rocket generate approximately 1.5 million pounds of thrust.
Thaicom-8 was built by aerospace competitor Orbital ATK, based in Dulles, VA. It will support Thailand’s growing broadcast industry and will provide broadcast and data services to customers in South Asia, Southeast Asia and Africa.
Thaicom-8 communications satellite built by Orbital ATK will launch on SpaceX Falcon 9 on May 26, 2016. The satellite has delivered to the launch site in Cape Canaveral, Florida in late April 2016. Credit: Orbital ATK
The Falcon 9 launch is the 5th this year for SpaceX.
Meanwhile, the first stage began a series of propulsive burns of a Merlin 1 D engine to target a drone ship platform at sea.
SpaceX said the barge was positioned some 620 km off the Florida coast in the Atlantic Ocean.
After the primary goal of delivering Thaicom-8 to GTO, the secondary test objective of SpaceX was to land the Falcon 9 rockets first stage on the ocean going barge.
The Autonomous Spaceport Drone Ship (ASDS) platform is named “Of Course I Still Love You.”
SpaceX Falcon 9 aloft with Thaicom-8 communications satellite after afternoon liftoff from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL on May 27, 2016. Credit: Ken Kremer/kenkremer.com
However with this mission’s GTO destination, the first stage was subject to extreme velocities and re-entry heating and a successful landing would be difficult.
Altogether, SpaceX has now recovered 4 first stage boosters – 3 by sea and 1 by land.
The quartet of landings count as stunning successes towards SpaceX founder and CEO Elon Musk’s vision of rocket reusability and radically slashing the cost of sending rockets to space by recovering the boosters and eventually reflying them with new payloads from paying customers.
SpaceX hopes to cut launch costs by one third initially, and much much more down the road.
Watch for Ken’s on site reports direct from Cape Canaveral and the SpaceX launch pad.
SpaceX Falcon 9 arcs over eastwards with Thaicom-8 communications satellite after liftoff from Space Launch Complex 40 at Cape Canaveral Air Force Station, FL on May 27, 2016. Credit: Ken Kremer/kenkremer.com
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
THAICOM 8 spacecraft as seen during deployment into a nominal supersynch transfer orbit. Credit: SpaceX
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Learn more about SpaceX Falcon 9 rocket, ULA Atlas rocket, Orbital ATK Cygnus, ISS, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken’s upcoming outreach events:
May 28: “SpaceX, ULA, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, afternoon/evening
Falcon 9 first stage landed on the droneship in the Atlantic Ocean after launch of Thaicom-8 on May 27, 2016. Credit: SpaceX
The 2006 Cleveland Volcano Eruption viewed from space. Credit: NASA
Volcanoes come in many shapes and sizes, ranging from common cinder cone volcanoes that build up from repeated eruptions and lava domes that pile up over volcanic vents to broad shield volcanoes and composite volcanoes. Though they differ in terms of structure and appearance, they all share two things. On the one hand, they are all awesome forces of nature that both terrify and inspire.
On the other, all volcanic activity comes down to the same basic principle. In essence, all eruptions are the result of magma from beneath the Earth being pushed up to the surface where it erupts as lava, ash and rock. But what mechanisms drive this process? What is it exactly that makes molten rock rise from the Earth’s interior and explode onto the landscape?
To understand how volcanoes erupt, one first needs to consider the structure of the Earth. At the very top is the lithosphere, the outermost layers of the Earth that consists of the upper mantle and crust. The crust makes up a tiny volume of the Earth, ranging from 10 km in thickness on the ocean floor to a maximum of 100 km in mountainous regions. It is cold and rigid, and composed primarily of silicate rock.
The Earth’s layers, showing the Inner and Outer Core, the Mantle, and Crust. Credit: discovermagazine.com
Beneath the crust, the Earth’s mantle is divided into sections of varying thickness based on their seismology. These consist of the upper mantle, which extends from a depth of 7 – 35 km (4.3 to 21.7 mi)) to 410 km (250 mi); the transition zone, which ranges from 410–660 km (250–410 mi); the lower mantle, which ranges from 660–2,891 km (410–1,796 mi); and the core–mantle boundary, which is ~200 km (120 mi) thick on average.
In the mantle region, conditions change drastically from the crust. Pressures increase considerably and temperatures can reach up to 1000 °C, which makes the rock viscous enough that it behaves like a liquid. In short, it experiences elastically on time scales of thousands of years or greater. This viscous, molten rock collects into vast chambers beneath the Earth’s crust.
Since this magma is less dense than the surrounding rock, it ” floats” up to the surface, seeking out cracks and weaknesses in the mantle. When it finally reaches the surface, it explodes from the summit of a volcano. When it’s beneath the surface, the molten rock is called magma. When it reaches the surface, it erupts as lava, ash and volcanic rocks.
The Earth’s Tectonic Plates. Credit: msnucleus.org
With each eruption, rocks, lava and ash build up around the volcanic vent. The nature of the eruption depends on the viscosity of the magma. When the lava flows easily, it can travel far and create wide shield volcanoes. When the lava is very thick, it creates a more familiar cone volcano shape (aka. a cinder cone volcano). When the lava is extremely thick, it can build up in the volcano and explode (lava domes).
Another mechanism that drives volcanism is the motion the crust undergoes. To break it down, the lithosphere is divided into several plates, which are constantly in motion atop the mantle. Sometimes the plates collide, pull apart, or slide alongside each other; resulting in convergent boundaries, divergent boundaries, and transform boundaries. This activity is what drives geological activity, which includes earthquakes and volcanoes.
In the case of the former, subduction zones are often the result, where the heavier plate slips under the lighter plate – forming a deep trench. This subduction changes the dense mantle into buoyant magma, which rises through the crust to the Earth’s surface. Over millions of years, this rising magma creates a series of active volcanoes known as a volcanic arc.
Cross-section of a volcano. Credit: 3dgeography.co.uk
In short, volcanoes are driven by pressure and heat in the mantle, as well as tectonic activity that leads to volcanic eruptions and geological renewal. The prevalence of volcanic eruptions in certain regions of the world – such as the Pacific Ring of Fire – also has a profound impact on the local climate and geography. For example, such regions are generally mountainous, have rich soil, and periodically experience the formation of new landmasses.
Few forces in nature are are impressive or frightening as a volcanic eruption. In an instant, from within the rumbling depths of the Earth, hot lava, steam, and even chunks of hot rock are spewed into the air, covering vast distances with fire and ash. And thanks to the efforts of geologists and Earth scientists over the course of many centuries, we have to come to understand a great deal about them.
However, when it comes to the nomenclature of volcanoes, a point of confusion often arises. Again and again, one of the most common questions about volcanoes is, what is the difference between lava and magma? They are both molten rock, and are both associated with volcanism. So why the separate names? As it turns out, it all comes down to location.
Earth’s Composition:
As anyone with a basic knowledge of geology will tell you, the insides of the Earth are very hot. As a terrestrial planet, its interior is differentiated between a molten, metal core, and a mantle and crust composed primarily of silicate rock. Life as we know it, consisting of all vegetation and land animals, live on the cool crust, whereas sea life inhabits the oceans that cover a large extent of this same crust.
The Earth’s layers, showing the Inner and Outer Core, the Mantle, and Crust. Credit: discovermagazine.com
However, the deeper one goes into the planet, both pressures and temperatures increase considerably. All told, Earth’s mantle extends to a depth of about 2,890 km, and is composed of silicate rocks that are rich in iron and magnesium relative to the overlying crust. Although solid, the high temperatures within the mantle cause pockets of molten rock to form.
This silicate material is less dense than the surrounding rock, and is therefore sufficiently ductile that it can flow on very long timescales. Over time, it will also reach the surface as geological forces push it upwards. This happens as a result of tectonic activity.
Basically, the cool, rigid crust is broken into pieces called tectonic plates. These plates are rigid segments that move in relation to one another at one of three types of plate boundaries. These are known as convergent boundaries, at which two plates come together; divergent boundaries, at which two plates are pulled apart; and transform boundaries, in which two plates slide past one another laterally.
Interactions between these plates are what is what is volcanic activity (best exemplified by the “Pacific Ring of Fire“) as well as mountain-building. As the tectonic plates migrate across the planet, the ocean floor is subducted – the leading edge of one plate pushing under another. At the same time, mantle material will push up at divergent boundaries, forcing molten rock to the surface.
The Earth’s Tectonic Plates. Credit: msnucleus.org
Magma:
As already noted, both lava and magma are what results from rock superheated to the point where it becomes viscous and molten. But again, the location is the key. When this molten rock is still located within the Earth, it is known as magma. The name is derived from Greek, which translate to “thick unguent” (a word used to describe a viscous substance used for ointments or lubrication).
It is composed of molten or semi-molten rock, volatiles, solids (and sometimes crystals) that are found beneath the surface of the Earth. This vicious rock usually collects in a magma chamber beneath a volcano, or solidify underground to form an intrusion. Where it forms beneath a volcano, it can then be injected into cracks in rocks or issue out of volcanoes in eruptions. The temperature of magma ranges between 600 °C and 1600 °C.
Magma is also known to exist on other terrestrial planets in the Solar System (i.e. Mercury, Venus and Mars) as well as certain moons (Earth’s Moon and Jupiter’s moon Io). In addition to stable lava tubes being observed on Mercury, the Moon and Mars, powerful volcanoes have been observed on Io that are capable of sending lava jets 500 km (300 miles) into space.
Igneous rock (aka. “fire rock”) is formed from cooled and solidified lava. Credit: geologyclass.org
Lava:
When magma reaches the surface and erupts from a volcano, it officially becomes lava. There are actually different kinds of lava depending on its thickness or viscosity. Whereas the thinnest lava can flow downhill for many kilometers (thus creating a gentle slope), thicker lavas will pile up around a volcanic vent and hardly flow at all. The thickest lava doesn’t even flow, and just plugs up the throat of a volcano, which in some cases cause violent explosions.
The term lava is usually used instead of lava flow. This describes a moving outpouring of lava, which occurs when a non-explosive effusive eruption takes place. Once a flow has stopped moving, the lava solidifies to form igneous rock. Although lava can be up to 100,000 times more viscous than water, lava can flow over great distances before cooling and solidifying.
The word “lava” comes from Italian, and is probably derived from the Latin word labes which means “a fall” or “slide”. The first use in connection with a volcanic event was apparently in a short written account by Franscesco Serao, who observed the eruption of Mount Vesuvius between May 14th and June 4th, 1737. Serao described “a flow of fiery lava” as an analogy to the flow of water and mud down the flanks of the volcano following heavy rain.
Such is the difference between magma and lava. It seems that in geology, as in real estate, its all about location!
This is an artist’s depiction of a 10-kilometer (6-mile) diameter asteroid striking the Earth. New evidence in Australia suggests an asteroid 2 to 3 times larger than this struck Earth early in its life. Credit: Don Davis/Southwest Research Institute.
New evidence found in northwestern Australia suggests that a massive asteroid, 20 to 30 kilometres in diameter, struck Earth about 3.5 billion years ago. This impact would have dwarfed anything experienced by humans, and dinosaurs, releasing as much energy as millions of nuclear weapons. Impacts this large can trigger earthquakes and tsunamis, and change the geological history of Earth.
The evidence was uncovered by Andrew Glikson and Arthur Hickman from the Australian National University. While drilling for the Geological Survey of Western Australia, the two obtained drilling cores from some of the oldest known sediments on Earth. Sandwiched between two layers of sediment were tiny glass beads called spherules, which were formed from vaporized material from the asteroid impact.
Impact spherules formed from material vaporized by an asteroid impact. Image: A. Glikson/Australian National University
The enormity of this impact cannot be overstated. “The impact would have triggered earthquakes orders of magnitude greater than terrestrial earthquakes, it would have caused huge tsunamis and would have made cliffs crumble,” said Dr. Glikson, from the ANU Planetary Institute.
This asteroid impact is the second oldest one that we know of. It is also one of the largest found yet, and at 20 to 30 kilometers in diameter, it is 2 the 3 times the size of the famous Chicxulub asteroid that struck the Yucatan in Mexico. That impact is thought to be responsible for ending the age of dinosaurs on Earth.
This image shows a very faint circular outline of the Chicxulub crater. After 65 million years, it is barely visible. All evidence of craters billions of years old would now be gone. Image: NASA/JPL
The crater itself would have been hundreds of kilometers in diameter, though all traces of it are now gone. “Exactly where this asteroid struck the earth remains a mystery,” Dr. Glikson said. “Any craters from this time on Earth’s surface have been obliterated by volcanic activity and tectonic movements.”
“Material from the impact would have spread worldwide. These spherules were found in sea floor sediments that date from 3.46 billion years ago,” said Glikson.
At 3.46 billion years ago, this puts this impact event close to a period of time 4.1 to 3.8 billion years ago known as the Late Heavy Bombardment. This was a period of time when a disproportionate number of asteroids struck the Earth and the Moon, and probably Mercury, Venus, and Mars, too. The Late Heavy Bombardment was probably caused by the gas giants in our Solar System. As these planets migrated, their gravity caused enormous disruption, pulling objects in the asteroid belt and the Kuiper Belt into trajectories that sent them towards the inner Solar System.
The Late Heavy Bombardment is thought to be a period of time when the Earth, and the rest of the bodies in the inner Solar System, were repeatedly struck by asteroids. Image: NASA/ESA
The surfaces of Mercury and the Moon are covered in impact craters. Samples of rock from the lunar surface, brought back to Earth by the Apollo astronauts, have been subjected to isotopic dating. Their age is constrained to a fairly narrow band of time, corresponding to the Late Heavy Bombardment. Obviously, the Earth would have been subjected to the same thing. But on geologically active Earth, most traces of impact events have been erased. It’s the sediment that hints at these events.
Australia is geologically ancient, and contains some of the most ancient rocks on Earth. Glikson and Hickman found the glass spherules in cores while drilling at Marble Bar in north-western Australia. Because the sediment layer containing the spherules was preserved between two volcanic layers, its age was determined with great precision.
The sediments at Marble Bar, north-western Australia, where the spherules were found. Image: A Glikson/Australian National University
For over 20 years, Dr. Glikson has been searching for evidence of asteroid impacts. When these glass beads were found in the core samples, he suspected an asteroid impact. Testing confirmed that the levels of elements such as platinum, nickel and chromium, matched those in asteroids.
This is not the first evidence of impact events that Glikson has uncovered. In 2015, Glikson discovered evidence of another massive asteroid strike in the Warburton Basin in Central Australia. At that site, buried in the crust 30 kilometers deep, in rock that is 300 to 500 million years old, Glikson found evidence of a double impact crater covering an area 400 kilometers wide.
This crater was believed to be the result of an asteroid that broke into two before slamming into Earth. “The two asteroids must each have been over 10 kilometers (6.2 miles) across — it would have been curtains for many life species on the planet at the time,” said Glikson.
“There may have been many more similar impacts, for which the evidence has not been found, said Dr. Glikson. “This is just the tip of the iceberg. We’ve only found evidence for 17 impacts older than 2.5 billion years, but there could have been hundreds.”
Finding the sites of ancient impacts is not easy. Advances in satellite imaging helped locate and pinpoint the Chicxulub crater, and others. If there have been hundreds of enormous asteroid impacts, like Dr. Glikson suggests, then they would have had an equally enormous impact on Earth’s evolution. But pinpointing these sites remains elusive.
Artist's impression of the Earth scorched by our Sun as it enters its Red Giant Branch phase. Credit: Wikimedia Commons/Fsgregs
Since the beginning of human history, people have understood that the Sun is a central part of life as we know it. It’s importance to countless mythological and cosmological systems across the globe is a testament to this. But as our understand of it matured, we came to learn that the Sun was here long before us, and will be here long after we’re gone. Having formed roughly 4.6 bullion years ago, our Sun began its life roughly 40 million years before our Earth had formed.
Since then, the Sun has been in what is known as its Main Sequence, where nuclear fusion in its core causes it to emit energy and light, keeping us here on Earth nourished. This will last for another 4.5 – 5.5 billion years, at which point it will deplete its supply of hydrogen and helium and go through some serious changes. Assuming humanity is still alive and calls Earth home at this time, we may want to consider getting out the way!
The Birth of Our Sun:
The predominant theory on how our Sun and Solar System formed is known as Nebular Theory, which states that the Sun and all the planets began billions of years ago as a giant cloud of molecular gas and dust. Then, approximately 4.57 billion years ago, this cloud experienced gravitational collapse at its center, where anything from a passing star to a shock wave caused by a supernova triggered the process that led to our Sun’s birth.
Basically, this took place after pockets of dust and gas began to collect into denser regions. As these regions pulled in more and more matter, conservation of momentum caused them to begin rotating, while increasing pressure caused them to heat up. Most of the material ended up in a ball at the center while the rest of the matter was flattened out into a large disk that circled around it.
Young stars have a disk of gas and dust around them called a protoplanetary disk. Out of this disk planets are formed, and the presence of water ice in the disc affects where different types of planets form. Credit: NASA/JPL-Caltech
The ball at the center would eventually form the Sun, while the disk of material would form the planets. The Sun then spent the next 100,000 years as a collapsing protostar before temperature and pressures in the interior ignited fusion at its core. The Sun started as a T Tauri star – a wildly active star that blasted out an intense solar wind. And just a few million years later, it settled down into its current form.
Main Sequence:
For the past 4.57 billion years (give or take a day or two), the Sun has been in the Main Sequence of its life. This is characterized by the process where hydrogen fuel, under tremendous pressure and temperatures in its core, is converted into helium. In addition to changing the properties of its constituent matter, this process also produces a tremendous amount of energy. All told, every second, 600 million tons of matter are converted into neutrinos, solar radiation, and roughly 4 x 1027 Watts of energy.
Naturally, this process cannot last forever since it is dependent on the presence of matter which is being regularly consumed. As time goes on and more hydrogen is converted into helium, the core will continue to shrink, allowing the outer layers of the Sun to move closer to the center and experience a stronger gravitational force.
This will place more pressure on the core, which is resisted by a resulting increase in the rate at which fusion occurs. Basically, this means that as the Sun continues to expend hydrogen in its core, the fusion process speeds up and the output of the Sun increases. At present, this is leading to a 1% increase in luminosity every 100 million years, and a 30% increase over the course of the last 4.5 billion years.
The life cycle of a Sun-like star, from its birth on the left side of the frame to its evolution into a red giant on the right after billions of years. Credit: ESO/M. Kornmesser
Approximately 1.1 billion years from now, the Sun will be 10% brighter than it is today. This increase in luminosity will also mean an increase in heat energy, one which the Earth’s atmosphere will absorb. This will trigger a runaway greenhouse effect that is similar to what turned Venus into the terrible hothouse it is today.
In 3.5 billion years, the Sun will be 40% brighter than it is right now, which will cause the oceans to boil, the ice caps to permanently melt, and all water vapor in the atmosphere to be lost to space. Under these conditions, life as we know it will be unable to survive anywhere on the surface, and planet Earth will be fully transformed into another hot, dry world, just like Venus.
Red Giant Phase:
In 5.4 billion years from now, the Sun will enter what is known as the Red Giant phase of its evolution. This will begin once all hydrogen is exhausted in the core and the inert helium ash that has built up there becomes unstable and collapses under its own weight. This will cause the core to heat up and get denser, causing the Sun to grow in size.
It is calculated that the expanding Sun will grow large enough to encompass the orbit’s of Mercury, Venus, and maybe even Earth. Even if the Earth were to survive being consumed, its new proximity to the the intense heat of this red sun would scorch our planet and make it completely impossible for life to survive. However, astronomers have noted that as the Sun expands, the orbit of the planet’s is likely to change as well.
When the Sun reaches this late stage in its stellar evolution, it will lose a tremendous amount of mass through powerful stellar winds. Basically, as it grows, it loses mass, causing the planets to spiral outwards. So the question is, will the expanding Sun overtake the planets spiraling outwards, or will Earth (and maybe even Venus) escape its grasp?
K.-P Schroder and Robert Cannon Smith are two researchers who have addressed this very question. In a research paper entitled “Distant Future of the Sun and Earth Revisted” which appeared in the Monthly Notices of the Royal Astronomical Society, they ran the calculations with the most current models of stellar evolution.
According to Schroder and Smith, when the Sun becomes a red giant star in 7.59 billion years, it will start to lose mass quickly. By the time it reaches its largest radius, 256 times its current size, it will be down to only 67% of its current mass. When the Sun does begin to expand, it will do so quickly, sweeping through the inner Solar System in just 5 million years.
It will then enter its relatively brief (130 million year) helium-burning phase, at which point, it will expand past the orbit of Mercury, and then Venus. By the time it approaches the Earth, it will be losing 4.9 x 1020 tonnes of mass every year (8% the mass of the Earth).
But Will Earth Survive?:
Now this is where things become a bit of a “good news/bad news” situation. The bad news, according to Schroder and Smith, is that the Earth will NOT survive the Sun’s expansion. Even though the Earth could expand to an orbit 50% more distant than where it is today (1.5 AUs), it won’t get the chance. The expanding Sun will engulf the Earth just before it reaches the tip of the red giant phase, and the Sun would still have another 0.25 AU and 500,000 years to grow.
Artist’s impression of a Red giant star. Credit:NASA/ Walt Feimer
Once inside the Sun’s atmosphere, the Earth will collide with particles of gas. Its orbit will decay, and it will spiral inward. If the Earth were just a little further from the Sun right now, at 1.15 AU, it would be able to survive the expansion phase. If we could push our planet out to this distance, we’d also be in business. However, such talk is entirely speculative and in the realm of science fiction at the moment.
And now for the good news. Long before our Sun enters it’s Red Giant phase, its habitable zone (as we know it) will be gone. Astronomers estimate that this zone will expand past the Earth’s orbit in about a billion years. The heating Sun will evaporate the Earth’s oceans away, and then solar radiation will blast away the hydrogen from the water. The Earth will never have oceans again, and it will eventually become molten.
Yeah, that’s the good news… sort of. But the upside to this is that we can say with confidence that humanity will be compelled to leave the nest long before it is engulfed by the Sun. And given the fact that we are dealing with timelines that are far beyond anything we can truly deal with, we can’t even be sure that some other cataclysmic event won’t claim us sooner, or that we wont have moved far past our current evolutionary phase.
An interesting side benefit will be how the changing boundaries of our Sun’s habitable zone will change the Solar System as well. While Earth, at a mere 1.5 AUs, will no longer be within the Sun’s habitable zone, much of the outer Solar System will be. This new habitable zone will stretch from 49.4 AU to 71.4 AU – well into the Kuiper Belt – which means the formerly icy worlds will melt, and liquid water will be present beyond the orbit of Pluto.
Perhaps Eris will be our new homeworld, the dwarf planet of Pluto will be the new Venus, and Haumeau, Makemake, and the rest will be the outer “Solar System”. But what is perhaps most fascinating about all of this is how humans are even tempted to ask “will it still be here in the future” in the first place, especially when that future is billions of years from now.
Somehow, the subjects of what came before us, and what will be here when we’re gone, continue to fascinate us. And when dealing with things like our Sun, the Earth, and the known Universe, it becomes downright necessary. Our existence thus far has been a flash in the pan compared to the cosmos, and how long we will endure remains an open question.
