Astronomers Discover Dizzying Spin Of The Milky Way Galaxy’s ‘Halo’

Astronomers at the University of Michigan’s College of Literature, Science, and the Arts (LSA) discovered for the first time that the hot gas in the halo of the Milky Way galaxy is spinning in the same direction and at comparable speed as the galaxy’s disk, which contains our stars, planets, gas, and dust.

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This new knowledge sheds light on how individual atoms have assembled into stars, planets, and galaxies like our own, and what the future holds for these galaxies.

“This flies in the face of expectations,” says Edmund Hodges-Kluck, assistant research scientist. “People just assumed that the disk of the Milky Way spins while this enormous reservoir of hot gas is stationary – but that is wrong. This hot gas reservoir is rotating as well, just not quite as fast as the disk.”

The new NASA-funded research using the archival data obtained by XMM-Newton, a European Space Agency telescope, was recently published in the Astrophysical Journal. The study focuses on our galaxy’s hot gaseous halo, which is several times larger than the Milky Way disk and composed of ionized plasma.

Because motion produces a shift in the wavelength of light, the U-M researchers measured such shifts around the sky using lines of very hot oxygen. What they found was groundbreaking: The line shifts measured by the researchers show that the galaxy’s halo spins in the same direction as the disk of the Milky Way and at a similar speed—about 400,000 mph for the halo versus 540,000 mph for the disk.

“The rotation of the hot halo is an incredible clue to how the Milky Way formed,” said Hodges Kluck. “It tells us that this hot atmosphere is the original source of a lot of the matter in the disk.”

Scientists have long puzzled over why almost all galaxies, including the Milky Way, seem to lack most of the matter that they otherwise would expect to find. Astronomers believe that about 80% of the matter in the universe is the mysterious “dark matter” that, so far, can only be detected by its gravitational pull. But even most of the remaining 20% of “normal” matter is missing from galaxy disks. More recently, some of the “missing” matter has been discovered in the halo. The U-M researchers say that learning about the direction and speed of the spinning halo can help us learn both how the material got there in the first place, and the rate at which we expect the matter to settle into the galaxy.

“Now that we know about the rotation, theorists will begin to use this to learn how our Milky Way galaxy formed – and its eventual destiny,” says Joel Bregman, a U-M LSA professor of astronomy.

“We can use this discovery to learn so much more – the rotation of this hot halo will be a big topic of future X-ray spectrographs,” Bregman says.

PART-II Nearby Supernovae Found to have Affected Life on Earth

The surface of the Earth was immersed in life-damaging radiation from nearby supernovae on several different occasions over the past nine million years. That is the claim of an international team of astronomers, which has created a computer model that suggests that high-energy particles from the supernovae created ionizing radiation in Earth’s atmosphere that reached ground level. This influx of radiation, the astronomers say, potentially changed the course of the Earth’s climate and the evolution of life.

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Earlier this year, two independent teams of astronomers published evidence that several supernovae had exploded some 330 light-years from Earth. Each event showered the solar system in iron-60, an overabundance of which has been found in core samples from the bottom of the Atlantic, Pacific and Indian oceans. A discovery of the same element ‘iron-60’ was found on the moon.

Iron-60 is not all that supernovae produce – they also produce cosmic rays, which are composed of high-energy electrons and atomic nuclei. Previous work by Neil Gehrels of NASA’s Goddard Space Flight Center, was found to be incorrect as he indicated that a supernova would have to explode within 25 light-years of Earth to give our planet a radiation dose strong enough to cause a major mass extinction.

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Now, a team led by Brian Thomas of Washburn University, and Adrian Melott of the University of Kansas argues that this conclusion is incorrect. The researchers looked at what would happen if a supernova exploded at a distance of 325 light-years and worked-out how its radiation would affect Earth. They found that cosmic rays accelerated towards Earth by the supernova are a different story. These have energies in the teraelectronvolt (TeV) region and are able to “pass right through the solar wind and Earth’s magnetic field and propagate much further into the atmosphere than cosmic rays normally do.”, says Melott.

When a cosmic ray strikes an air molecule, it produces a shower of secondary particles that is filled with the likes of protons, neutrons and a strong flux of muons. Ordinarily this takes place in the upper atmosphere and can be responsible for ionizing and destroying ozone in the stratosphere. However, the supernova cosmic rays are so energetic that they will pass straight through the stratosphere, lower atmosphere, and down to the surface and deep into the oceans and mantle.

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Today, muons contribute a sixth of our annual radiation dose, however, the team calculated a supernova hit would result in a 20-fold increase in the muon flux that would triple the annual radiation dose of life forms on the planet.

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IMPORTANT ARTICLE: Greater Concern of Cosmic Rays Effect to Earth Then I Realized

As you will see from the following article, it is one of many describing findings from the latest research and studies related to galactic cosmic rays. What I find to be a bit perplexing, is the amount and method of delivery from the science community regarding cosmic rays. It would appear scientific data is coming in at record pace via the incredible spacecraft such as  HERSCHEL, PLANK, CHANDRA, and WISE, and researchers are hard pressed to disseminate their findings in published papers.

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As related to my research on the Galaxy-Sun-Earth connection published in 2012, it appears to have hit almost every note presented, however, apparently I under estimated the foretelling possibilities galactic cosmic rays could have on Earth. There is quite a bit of data flowing out, much of which has to do with recent discoveries indicating supernovae explosions hitting Earth; and was the source of at least two ‘mass’ extinctions, and very likely the source of ‘partial’ extinctions.

New Equation:
Increase Charged Particles → Decreased Magnetic Field → Increase Outer Core Convection → Increase of Mantle Plumes → Increase in Earthquake and Volcanoes → Cools Mantle and Outer Core → Return of Outer Core Convection (Mitch Battros – July 2012)

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There is a great deal to present to you so this will be a 3 or 4 part article with this as Part-I. Below is one of the latest published findings showing the desire to, better and perhaps quickly, understand the pre and post eruptions, and most importantly, the rhythmic cycles.

STAY TUNED…………..

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Astronomers have uncovered the strongest evidence yet exhibiting an enormous X-shaped structure made of stars that lies within the central bulge of the Milky Way Galaxy. Previous computer models showing observations of other galaxies – including our own galaxy Milky Way, suggesting the X-shaped structure does exist. However, no one had observed it directly, and some astronomers argued that previous research pointed indirectly to the existence of the X, but that it could be explained in other ways.

Lead author is Melissa Ness, researcher at the Max Planck Institute for Astronomy in Heidelberg, along with Dustin Lang, research associate at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics, and co-author of the paper describing the discovery. Lang says: “Controversy about whether the X-shaped structure existed, but our paper furnishes an authoritative composition of our own Milky Way’s galactic core. The results appear in the July issue of the Astronomical Journal.

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The Milky Way Galaxy is a barred spiral galaxy; a disk-shaped collection of dust, gas and billions of stars, 100,000 light-years in diameter. It is far from a simple disk structure, being comprised of two spiral arms, a bar-shaped feature that runs through its center, and a central bulge of stars. The central bulge, like other barred galaxy’s bulges, resembles a rectangular box or peanut as viewed from within the plane of the galaxy. The X-shaped structure is an integral component of the bulge.

“The bulge is a key signature of formation of the Milky Way Galaxy,” says Ness. “If we understand the bulge we will understand the key processes which had formed and shaped our galaxy.”

“The shape of the bulge tells us about how it has formed. We see the X-shape and boxy morphology so clearly in the WISE image, demonstrating the internal formation processes have been the ones driving the bulge formation.”

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It is also evidence that our galaxy did not experience major merging events since the bulge formed. If it had, interactions with other galaxies would have disrupted its shape.

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Alien Solar System Boasts Tightly Spaced Planets, Unusual Orbits

Tightly spaced planets inside an alien solar system known as Kepler-80 boast a rare orbital configuration.

The study was led by Mariah MacDonald as an undergraduate with Darin Ragozzine, an assistant professor of physics and space sciences, both at Florida Institute of Technology.

The unusual planetary array highlighted in the study deepens the ongoing examination of similar systems known as STIPs – Systems with Tightly-spaced Inner Planets – and contributes to the understanding of how Earth formed.

Located about 1,100 light years away, Kepler-80, named for the NASA telescope that discovered it, features five small planets orbiting in extreme proximity to their star. MacDonald and Ragozzine determined the nature of the exoplanetary system through measurements taken with the telescope.

As early as 2012, Kepler scientists found that all five planets orbit in an area about 150 times smaller than the Earth’s orbit around the Sun, with “years” of about one, three, four, seven and nine days. The planets’ close proximity to each other and their star allowed the Kepler Space Telescope to detect tiny variations (about 0.001 percent) in the length of their “years” due to their mutual gravitational interactions.

Analysis by MacDonald and her collaborators revealed that the outer four planets had masses about four- to six-times that of Earth, though they shared Earth’s rocky composition. All four planets have masses similar to one another, though the two outermost planets are almost twice as big. This was attributed to a very puffy hydrogen/helium atmosphere.

These properties are not uncommon for exoplanets, but having precise compositional estimates for multiple planets in the same planetary system is rare.
Another rare attribute of the Kepler-80 system is that its planets have “synchronized” orbits. “The outer four planets return to almost exactly the same configuration every 27 days,” said Ragozzine. This effect is known as a “resonance” and helps the system remain gravitationally stable.

The study also explained the origin of the synchronized orbits in general – and possibly the tightly-spaced configuration. In a process called migration, the orbits of these planets shrank over time while they were forming. Simulations clearly showed that this migration effect caused the planets to lock into synchronized orbits just like those seen with Kepler-80.

Kepler has discovered hundreds of other STIPs, which consist of three to seven relatively small and closely packed planets that complete orbits in 1 to 100 days. This new form of planetary system, quite different from our own solar system, is changing the way scientists think about how planets form, including the Earth. With all the knowledge gained by the analysis of Kepler-80, this system is granting important insight into how STIPs formed.

First Atmospheric Study Of Earth-Sized Exoplanets Reveals Rocky Worlds

On May 2, scientists from MIT, the University of Liège, and elsewhere announced they had discovered a planetary system, a mere 40 light years from Earth, that hosts three potentially habitable, Earth-sized worlds. Judging from the size and temperature of the planets, the researchers determined that regions of each planet may be suitable for life.

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Now, in a paper published today in Nature, that same group reports that the two innermost planets in the system are primarily rocky, unlike gas giants such as Jupiter. The findings further strengthen the case that these planets may indeed be habitable. The researchers also determined that the atmospheres of both planets are likely not large and diffuse, like that of the Jupiter, but instead compact, similar to the atmospheres of Earth, Venus, and Mars.

The scientists, led by first author Julien de Wit, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences, came to their conclusion after making a preliminary screening of the planets’ atmospheres, just days after announcing the discovery of the planetary system.

On May 4, the team commandeered NASA’s Hubble Space Telescope and pointed it at the system’s star, TRAPPIST-1, to catch a rare event: a double transit, the moment when two planets almost simultaneously pass in front of their star. The researchers realized the planets would transit just two weeks before the event, thanks to refined estimates of the planets’ orbital configuration, made by NASA’s Spitzer Space Telescope, which had already started to observe the TRAPPIST-1 system.

“We thought, maybe we could see if people at Hubble would give us time to do this observation, so we wrote the proposal in less than 24 hours, sent it out, and it was reviewed immediately,” de Wit recalls. “Now for the first time we have spectroscopic observations of a double transit, which allows us to get insight on the atmosphere of both planets at the same time.”

Using Hubble, the team recorded a combined transmission spectrum of TRAPPIST-1b and c, meaning that as first one planet then the other crossed in front of the star, they were able to measure the changes in wavelength as the amount of starlight dipped with each transit.

“The data turned out to be pristine, absolutely perfect, and the observations were the best that we could have expected,” de Wit says. “The force was certainly with us.”

A rocky sign

The dips in starlight were observed over a narrow range of wavelengths that turned out not to vary much over that range. If the dips had varied significantly, de Wit says, such a signal would have demonstrated the planets have light, large, and puffy atmospheres, similar to that of the gas giant Jupiter.

But that’s not the case. Instead, the data suggest that both transiting planets have more compact atmospheres, similar to those of rocky planets such as Earth, Venus, and Mars.

“Now we can say that these planets are rocky. Now the question is, what kind of atmosphere do they have?” de Wit says. “The plausible scenarios include something like Venus, where the atmosphere is dominated by carbon dioxide, or an Earth-like atmosphere with heavy clouds, or even something like Mars with a depleted atmosphere. The next step is to try to disentangle all these possible scenarios that exist for these terrestrial planets.”

More eyes on the sky

The scientists are now working to establish more telescopes on the ground to probe this planetary system further, as well as to discover other similar systems. The planetary system’s star, TRAPPIST-1, is known as an ultracool dwarf star, a type of star that is typically much cooler than the sun, emitting radiation in the infrared rather than the visible spectrum.

De Wit’s colleagues from the University of Liège came up with the idea to look for planets around such stars, as they are much fainter than typical stars and their starlight would not overpower the signal from planets themselves.

The researchers discovered the TRAPPIST-1 planetary system using TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope), a new kind of ground telescope designed to survey the sky in infrared. TRAPPIST was built as a 60-centimeter prototype to monitor the 70 brightest dwarf stars in the southern sky. Now, the researchers have formed a consortium, called SPECULOOS (Search for habitable Planets Eclipsing ULtra-cOOl Stars), and are building four larger versions of the telescope in Chile, to focus on the brightest ultracool dwarf stars in the skies over the southern hemisphere. The researchers are also trying to raise money to build telescopes in the northern sky.

“Each telescope is about $400,000—about the price of an apartment in Cambridge,” de Wit says.

If the scientists can train more TRAPPIST-like telescopes on the skies, de Wit says, the telescopes may serve as relatively affordable “prescreening tools.” That is, scientists may use them to identify candidate planets that just might be habitable, then follow up with more detailed observations using powerful telescopes such as Hubble and NASA’s James Webb Telescope, which is scheduled to launch in October 2018.

“With more observations using Hubble, and further down the road with James Webb, we can know not only what kind of atmosphere planets like TRAPPIST-1 have, but also what is within these atmospheres,” de Wit says. “And that’s very exciting.”

BREAKING NEWS: New Study Shakes Up Science Community Over Historic Cosmic Ray Blast

This news release goes to the heart of my research. It is as if the astrophysics science community comes clean, having hinted of the seriousness charged particles can do to our solar system and of course Earth. What I have been writing about over the last five years regarding possible scenarios based on factual historic data, pertaining to galactic cosmic rays, setting aside the short-term consequences of the Sun’s 22 year cycle apropos to the expansion and contraction of solar rays such as coronal mass ejections, solar flares, coronal holes and filaments.

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In short, (encourage you to read last 5 or 6 Science of Cycles newsletters) it is galactic cosmic rays which will usher in the upcoming magnetic reversal. It is these smaller, if not smallest charged particles as measured using a electromagnetic spectrometer which cause the most harmful effects to Earth’s core and humans.

I am placing original excerpts below so you can read the words used as to their emphasis in realizing events such as supernovae’s from our galaxy Milky Way, or perhaps even greater distances from neighboring galaxies or celestial orbs can have a profound effect to our solar system and planet.

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Research recently published provided empirical evidence of two prehistoric supernovae exploding about 300 light years from Earth. Now, a follow-up investigation based on computer modeling shows those supernovae likely propagated a significant biological shift on our planet to a long-lasting gust of cosmic radiation, which also affected the atmosphere.

“I was surprised to see as much effect as there was,” said Adrian Melott, professor of physics at the University of Kansas, who co-authored the new paper appearing in The Astrophysical Journal Letters, a peer-reviewed express scientific journal that allows astrophysicists to rapidly publish short notices of significant original research. “I was expecting there to be very little effect at all,” he said. “The supernovae were pretty far away – more than 300 light years – that’s really not very close.”

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According to Melott, “The big thing turns out to be the cosmic rays. The really high-energy ones are pretty rare. The high-energy cosmic rays are the ones that can penetrate the atmosphere. They tear up molecules, they can rip electrons off atoms, and that goes on right down to the ground level. Normally that happens only at high altitude.

Melott’s collaborators on the research are Brian Thomas and Emily Engler of Washburn University, Michael Kachelrieß of the Institutt for fysikk in Norway, Andrew Overholt of MidAmerica Nazarene University and Dimitry Semikoz of the Observatoire de Paris and Moscow Engineering Physics Institute.

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The boosted exposure to cosmic rays from supernovae could have had “substantial effects on the terrestrial atmosphere and fauna.” Fauna pretty much means ‘all living things’. For instance, the research suggested the supernovae might have caused a 20-fold increase in irradiation by muons at ground level on Earth.

“A muon is a cousin of the electron, a couple of hundred times heavier than the electron – they penetrate hundreds of meters of rock,” Melott said. “Normally there are lots of them hitting us on the ground. They mostly just go through us, but because of their large numbers contribute about 1/6 of our normal radiation dose. So if there were 20 times as many, you’re in the ballpark of tripling the radiation dose.”

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Melott said the uptick in radiation from muons would have been high enough to boost the mutation rate and frequency of cancer, but not enormously. Still, if you increased the mutation rate you might speed up evolution.

Indeed, a minor mass extinction around 2.59 million years ago may be connected in part to boosted cosmic rays that could have helped to cool Earth’s climate. The new research results show that the cosmic rays ionize the Earth’s atmosphere in the troposphere – the lowest level of the atmosphere – to a level eight times higher than normal. This would have caused an increase in cloud-to-ground lightning.

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Cosmic rays are inescapable throughout the universe. They can rip right through our atmosphere, damaging DNA and possibly causing cancer and memory loss over the long-term.

“There was climate change around this time,” Melott said. Africa dried out, and a lot of the forest turned into savannah. Around this time and afterwards, we started having glaciations – ice ages – over and over again, and it’s not clear why that started to happen. It’s controversial, but maybe cosmic rays had something to do with it.

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Breaking News: Is Earth’s Atmosphere Leaking?

A new study was released over the weekend stating Earth’s atmosphere is leaking. It is presented as if this is a new phenomena just learned and the researchers delivery paints a picture of scientists running around frantically as if they are huddled together thinking to themselves “oh shiet, we must plug the hole….”

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Here’s the fact: the Earth’s atmosphere has always been “leaking” – sometimes more than others. Once again, it truly is the Science of Cycles that wins the day. The question really at hand here is; what is the cause of these cyclical expansion and contraction periods? For those of you who have been following my work already know the answer. But of course there are always new people discovering ScienceOfCycles.com so I must present where my research leads us. Now I am very happy to say, it is not just my research but several other recently published papers from Universities and governmental agencies have also discovered this new awareness of cycles that extend to our galaxy Milky Way and beyond.

Our home Earth, protects us from most seriously dangerous radiation and electrical surges. It does so by creating a magnetic field which is produced through the geodynamic process of convection in the outer cores liquid iron producing currents.

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What we are witnessing today, is Earth’s natural ability to maintain its ambient rotation and orbital balance. Currently, the Earth’s magnetic field is weakening, which therefore allows a greater amount of charged particles and plasma to enter our atmosphere. As a result, Earth’s core begins to overheat. As a way to expend this overheating, Earth produces more mantle plumes which works their way up through the upper mantle, advances into the asthenoshpere, extends through the lithosphere, and breaks through the crust. This process markedly resembles that of humans  when become overheated ‘sweat’ through their pores cooling the body.

The opposite occurs when the Earth’s core becomes slightly too cool, then mantle plumes dissipate, oceans and atmosphere begin to cool and temperatures may fluctuate and lower…then the cycle starts all over again. The time period between these warming and cooling trends do in fact vary, however, they do maintain short-term, moderate, and long-term cycles. This could be 11 year, 100 year, 1000 year and etc.

I have no illusion of my work being recognized by the major world space agencies, I do not have the pedigree nor do I have some form of contractual agreement with them. However, I have been able to maintain my connection with some of the brightest scientists who do in fact work for said agencies and Universities. Some might call me a colleague, others I surely call my mentors. There will be a time in the not to distant future when you will see my 2012 Equation being announced to the public. But it will not be my name attached to this new discovery. I can assure you it will be one from our government space agency, or Europe or Netherlands. All of which is truly fine with me. And if it’s one with whom I have been working with, I will clap the loudest.

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Before I go on, I hope you will see this new release ties in with the last five or so released scientific papers. From my point of view they all point to the same direction. (see 2012 Equation)

(NASA) Earth’s atmosphere is leaking. Every day, around 90 tons of material escapes from our planet’s upper atmosphere and streams out into space. Although missions such as ESA’s Cluster fleet have long been investigating this leakage, there are still many open questions. How and why is Earth losing its atmosphere – and how is this relevant in our hunt for lie elsewhere in the Universe?

Given the expanse of our atmosphere, 90 tons per day amounts to a small leak. Earth’s atmosphere weighs in at around five quadrillion (5 × 1015) tons so we are in no danger of running out any time soon.

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We have been exploring Earth’s magnetic environment for years using satellites such as ESA’s Cluster mission, a fleet of four spacecraft launched in 2000. Cluster has been continuously observing the magnetic interactions between the Sun and Earth for over a decade and half; this longevity, combined with its multi-spacecraft capabilities and unique orbit, have made it a key player in understanding both Earth’s leaking atmosphere and how our planet interacts with the surrounding Solar System.

Earth’s magnetic field is complex; it extends from the interior of our planet out into space, exerting its influence over a region of space dubbed the magnetosphere.

The magnetosphere – and its inner region (the plasmasphere), a doughnut-shaped portion sitting atop our atmosphere, which co-rotates with Earth and extends to an average distance of 12,427 miles (20,000 km) – is flooded with charged particles and ions that are trapped, bouncing back and forth along field lines.

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At its outer sunward edge, the magnetosphere meets the solar wind, a continuous stream of charged particles – mostly protons and electrons – flowing from the Sun. Here, our magnetic field acts like a shield, deflecting and rerouting the incoming wind as a rock would obstruct a stream of water. This analogy can be continued for the side of Earth further from the Sun – particles within the solar wind are sculpted around our planet and slowly come back together, forming an elongated tube (named the magneto-tail), which contains trapped sheets of plasma and interacting field lines.

However, our magnetosphere shield does have its weaknesses; at Earth’s poles the field lines are open, like those of a standard bar magnet (these locations are named the polar cusps). Here, solar wind particles can head inwards towards Earth, filling up the magnetosphere with energetic particles.

Just as particles can head inwards down these open polar lines, particles can also head outwards. Ions from Earth’s upper atmosphere – the ionosphere, which extends to roughly 621 miles (1000 km) above the Earth – also flood out to fill up this region of space. Although missions such as Cluster have discovered much, the processes involved remain unclear.

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“The question of plasma transport and atmospheric loss is relevant for both planets and stars, and is an incredibly fascinating and important topic. Understanding how atmospheric matter escapes is crucial to understanding how life can develop on a planet,” said Arnaud Masson, ESA’s Deputy Project Scientist for the Cluster mission. “The interaction between incoming and outgoing material in Earth’s magnetosphere is a hot topic at the moment; where exactly is this stuff coming from? How did it enter our patch of space?”

Initially, scientists believed Earth’s magnetic environment to be filled purely with particles of solar origin. However, as early as the 1990s it was predicted that Earth’s atmosphere was leaking out into the plasmasphere – something that has since turned out to be true. Given the expanse of our atmosphere, 90 tons per day amounts to a small leak. Earth’s atmosphere weighs in at around five quadrillion (5 × 1015) tons so we are in no danger of running out any time soon.

Observations have shown sporadic, powerful columns of plasma, dubbed plumes, growing within the plasmasphere, travelling outwards to the edge of the magnetosphere and interacting with solar wind plasma entering the magnetosphere.

More recent studies have unambiguously confirmed another source – Earth’s atmosphere is constantly leaking! Alongside the aforementioned plumes, a steady, continuous flow of material (comprising oxygen, hydrogen and helium ions) leaves our planet’s plasmasphere from the polar regions, replenishing the plasma within the magnetosphere. Cluster found proof of this wind, and has quantified its strength for both overall (reported in a paper published in 2013) and for hydrogen ions in particular (reported in 2009).

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Overall, about 2.2 pounds (1 kg) of material is escaping our atmosphere every second, amounting to almost 90 tons per day. Singling out just cold ions (light hydrogen ions, which require less energy to escape and thus possess a lower energy in the magnetosphere), the escape mass totals thousands of tons per year.

Cold ions are important; many satellites – Cluster excluded – cannot detect them due to their low energies, but they form a significant part of the net matter loss from Earth, and may play a key role in shaping our magnetic environment.

Solar storms and periods of heightened solar activity appear to speed up Earth’s atmospheric loss significantly, by more than a factor of three. However, key questions remain: How do ions escape, and where do they originate? What processes are at play, and which is dominant? Where do the ions go? And how?

One of the key escape processes is thought to be centrifugal acceleration, which speeds up ions at Earth’s poles as they cross the shape-shifting magnetic field lines there. These ions are shunted onto different drift trajectories, gain energy and end up heading away from Earth into the magneto-tail, where they interact with plasma and return to Earth at far higher speeds than they departed with – a kind of boomerang effect.

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Such high-energy particles can pose a threat to space-based technology, so understanding them is important. Cluster has explored this process multiple times during the past decade and a half – finding it to affect heavier ions such as oxygen more than lighter ones, and detecting strong, high-speed beams of ions rocketing back to Earth from the magneto-tail nearly 100 times over the course of three years.

More recently, scientists have explored the process of magnetic reconnection, one of the most efficient physical processes by which the solar wind enters Earth’s magnetosphere and accelerates plasma. In this process, plasma interacts and exchanges energy with magnetic field lines; different lines reconfigure themselves, breaking, shifting around and forging new connections by merging with other lines, releasing huge amounts of energy in the process.

Here, the cold ions are thought to be important. We know that cold ions affect the magnetic reconnection process, for example slowing down the reconnection rate at the boundary where the solar wind meets the magnetosphere (the magnetopause), but we are still unsure of the mechanisms at play.

“In essence, we need to figure out how cold plasma ends up at the magnetopause,” said Philippe Escoubet, ESA’s Project Scientist for the Cluster mission. “There are a few different aspects to this; we need to know the processes involved in transporting it there, how these processes depend on the dynamic solar wind and the conditions of the magnetosphere, and where plasma is coming from in the first place – does it originate in the ionosphere, the plasmasphere, or somewhere else?”

Recently, scientists modeled and simulated Earth’s magnetic environment with a focus on structures known as plasmoids and flux ropes – cylinders, tubes, and loops of plasma that become tangled up with magnetic field lines. These arise when the magnetic reconnection process occurs in the magnetotail and ejects plasmoids both towards the outer tail and towards Earth.

Cold ions may play a significant role in deciding the direction of the ejected plasmoid. These recent simulations showed a link between plasmoids heading towards Earth and heavy oxygen ions leaking out from the ionosphere – in other words, oxygen ions may reduce and quench the reconnection rates at certain points within the magneto-tail that produce tail-ward trajectories, thus making it more favorable at other sites that instead send them Earthwards. These results agree with existing Cluster observations.

Another recent Cluster study compared the two main atmospheric escape mechanisms Earth experiences – sporadic plumes emanating through the plasmasphere, and the steady leakage of Earth’s atmosphere from the ionosphere – to see how they might contribute to the population of cold ions residing at the dayside magnetopause (the magnetosphere-solar wind boundary nearest the Sun).

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Both escape processes appear to depend in different ways on the Interplanetary Magnetic Field (IMF), the solar magnetic field that is carried out into the Solar System by the solar wind. This field moves through space in a spiraling pattern due to the rotation of the Sun, like water released from a lawn sprinkler. Depending on how the IMF is aligned, it can effectively cancel out part of Earth’s magnetic field at the magnetopause, linking up and merging with our field and allowing the solar wind to stream in.

Plumes seem to occur when the IMF is oriented southward (anti-parallel to Earth’s magnetic field, thus acting as mentioned above). Conversely, leaking outflows from the ionosphere occur during northward-oriented IMF. Both processes occur more strongly when the solar wind is either denser or travelling faster (thus exerting a higher dynamic pressure).

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“While there is still much to learn, we’ve been able to make great progress here,” said Masson. “These recent studies have managed to successfully link together multiple phenomena – namely the ionospheric leak, plumes from the plasmasphere, and magnetic reconnection – to paint a better picture of Earth’s magnetic environment. This research required several years of ongoing observation, something we could only get with Cluster.”