Archiv: magnetic reconnection / magnetospheres („flux transfer events“ / magnetic ropes)


26.04.2024 - 01:30 [ PRI.org ]

Scientists link Earth’s magnetic reversals to changes in planet’s life and climate

(April 19, 2021)

The researchers examined the rings of the tree to look for changes in the amount of carbon-14 over a period of years, Gramling explains. Carbon-14 is useful not only for dating things, but because the interaction of cosmic rays with molecules in the atmosphere produces a lot of it. And when the Earth has a weakened magnetic field, more cosmic rays hit the planet.

The scientists indeed found a large spike in carbon-14 in the tree, which they could then compare with the rock record that indicated a magnetic reversal. (…)

In addition, there is the documented rise in cave art right about 41,000-42,000 years ago, Gramling points out.

26.04.2024 - 00:00 [ Journal of Geophysical Research: Solid Earth / onlinelibrary.wiley.com ]

Possible Eoarchean Records of the Geomagnetic Field Preserved in the Isua Supracrustal Belt, Southern West Greenland

(24 April 2024)

The preservation of a temperate climate and liquid water on early Earth depends critically upon the strength of the magnetosphere (Sterenborg et al., 2011; Tarduno et al., 2014). Recent atmospheric escape models have suggested that both weak (<10 μT) and strong (>1 mT) magnetic fields could substantially enhance atmospheric escape under present-day solar wind conditions via the polar wind or cusp escape, respectively (Gronoff et al., 2020; Gunell et al., 2018; Lundin et al., 2007). During the Archean, the Sun was rotating faster, generating a stronger stellar dynamo and therefore the solar wind was more intense than today (Vidotto, 2021). An increased solar wind strength causes greater interaction with the upper atmosphere and greater escape of ions assuming a constant level of protection from Earth‘s magnetosphere. Previous magnetohydrodynamic simulations have suggested that if Earth‘s magnetic field was half its present day strength 3.5 Ga ago, the area of the polar cap (the area containing open dipolar magnetic field lines, allowing atmospheric escape via the polar wind) could increase by up to 50% (Sterenborg et al., 2011).

25.04.2024 - 23:52 [ IFLscience.com ]

The Earth’s Magnetic Field Is At Least 3.7-Billion-Years Old, New Evidence Shows

The age of the Earth’s magnetic field remains under question in part because we don’t fully understand what causes it today. We know it is a product of movements in the molten outer core, whose high iron content turns convection currents into a dynamo, and these currents in turn are produced by the solidification of the inner core.

25.04.2024 - 23:45 [ livescience.com ]

Earth‘s magnetic field formed before the planet‘s core, study suggests

(24 April 2024)

Today, the magnetic field is driven by the churning of the liquid part of the core and the transfer of heat from the solid inner core to the convective outer core as the former cools. But researchers think the core didn‘t solidify until about a billion years ago.

24.04.2023 - 15:18 [ New York Times ]

Northern Lights Are Seen in Places Where They Normally Aren’t

“The sun spit off a big blob of plasma,” Mr. Steenburgh said. The burst of energy, which has its own magnetic field, had been moving through space and reached Earth’s magnetic field on Sunday, when the two collided to create a geomagnetic storm, he said. “It got our magnetosphere pretty revved up.”

When this happens, the aurora can be seen closer to the Equator, Mr. Steenburgh said. Such events are not that uncommon, with about 100 occurring every 11 years, he said, adding that the storm can also disturb high frequency radio used at sea and by airlines.

24.04.2023 - 12:20 [ University of Maryland ]

Space Mission First to Observe Key Interaction Between Magnetic Fields of Earth and Sun

(12 May 2016)

Most people do not give much thought to the Earth’s magnetic field, yet it is every bit as essential to life as air, water and sunlight. The magnetic field provides an invisible, but crucial, barrier that protects Earth from the sun’s magnetic field, which drives a stream of charged particles known as the solar wind outward from the sun’s outer layers. The interaction between these two magnetic fields can cause explosive storms in the space near Earth, which can knock out satellites and cause problems here on Earth’s surface, despite the protection offered by Earth’s magnetic field.

A new study co-authored by University of Maryland physicists provides the first major results of NASA’s Magnetospheric Multiscale (MMS) mission, including an unprecedented look at the interaction between the magnetic fields of Earth and the sun. The paper describes the first direct and detailed observation of a phenomenon known as magnetic reconnection, which occurs when two opposing magnetic field lines break and reconnect with each other, releasing massive amounts of energy.

The discovery is a major milestone in understanding magnetism and space weather.

24.04.2023 - 12:17 [ National Aeronautics and Space Administration ]

Magnetic Portals Connect Earth to the Sun

Oct. 30, 2008: During the time it takes you to read this article, something will happen high overhead that until recently many scientists didn‘t believe in. A magnetic portal will open, linking Earth to the sun 93 million miles away. Tons of high-energy particles may flow through the opening before it closes again, around the time you reach the end of the page.

„It‘s called a flux transfer event or ‚FTE,'“ says space physicist David Sibeck of the Goddard Space Flight Center. „Ten years ago I was pretty sure they didn‘t exist, but now the evidence is incontrovertible.“

Indeed, today Sibeck is telling an international assembly of space physicists at the 2008 Plasma Workshop in Huntsville, Alabama, that FTEs are not just common, but possibly twice as common as anyone had ever imagined.

24.04.2023 - 07:39 [ San Francisco Chronicle ]

A severe geomagnetic storm could create rare ‚northern lights‘ sightings. Here’s what it means for Northern California

(23.04.2023)

Geomagnetic storms occur when energy from the sun’s outermost atmosphere disrupts Earth’s magnetic field, causing bands of green and red to light up the night sky. The natural electrical phenomenon is especially visible near the North Pole, but sometimes stretches lower into Canada and the northern United States, where it is often captured by wildfire cameras.

24.04.2023 - 07:36 [ DailyRecord.co.uk ]

Scots could see Northern Lights with aurora borealis ‚likely‘ tonight

(23.04.2023)

The natural light display – more typically visible in high-latitude regions around the Artic and Antarctic – is better seen in a dark location with no light pollution, with cloudless skies.

The atmospheric phenomenon is caused when solar particles from the sun collide with Earth‘s atmosphere. These energised particles combine with nitrogen and oxygen molecules, which send them into an excited state.

25.10.2021 - 19:22 [ arxiv.org ]

A Unified Model for the Fan Region and the North Polar Spur: A bundle of filaments in the Local Galaxy

We present a simple, unified model that can explain two of the brightest, large-scale, diffuse, polarizedradio features in the sky, the North Polar Spur (NPS) and the Fan Region, along with several otherprominent loops. We suggest that they are long, magnetized, and parallel filamentary structures thatsurround the Local arm and/or Local Bubble, in which the Sun is embedded. We show this modelis consistent with the large number of observational studies on these regions, and is able to resolvean apparent contradiction in the literature that suggests the high latitude portion of the NPS isnearby, while lower latitude portions are more distant. Understanding the contributions of this localemission is critical to developing a complete model of the Galactic magnetic field.

25.10.2021 - 19:18 [ Dunlap Institute for Astronomy & Astrophysics, University of Toronto ]

Dunlap Astronomer discovers we may be surrounded by tunnel-like structure

(Oct.14, 2021)

Dr. Jennifer West, Research Associate at the Dunlap Institute for Astronomy and Astrophysics, is making a scientific case that two bright structures that are seen on opposite sides of the sky – previously considered to be separate – are actually connected and are made of rope-like filaments. This connection forms what looks like a tunnel around our solar system.

“If we were to look up in the sky,” explains West, “we would see this tunnel-like structure in just about every direction we looked – that is, if we had eyes that could see radio light.”

25.10.2021 - 19:10 [ SciTechdaily.com ]

A Vast “Magnetic Tunnel” May Surround Earth and Our Entire Solar System

(today)

An expert in magnetism in galaxies and the interstellar medium, West looks forward to the more possible discoveries connected to this research.

“Magnetic fields don’t exist in isolation,” she says. “They all must to connect to each other. So, a next step is to better understand how this local magnetic field connects both to the larger-scale galactic magnetic field, and also to the smaller scale magnetic fields of our sun and Earth.”

25.10.2021 - 18:59 [ National Aeronautics and Space Administration ]

Studying the Edge of the Sun’s Magnetic Bubble

(Oct 19, 2021)

The space radiation that comes at us from other stars is called galactic cosmic radiation (GCR). Active areas in the galaxy – like supernovae, black holes, and neutron stars – can strip the electrons from atoms and accelerate the nuclei to almost the speed of light, producing GCR.

On Earth, we have three layers of protection from space radiation. The first is the heliosphere, which helps block GCR from reaching the major planets in the solar system. Additionally, Earth’s magnetic field produces a shield called the magnetosphere, which keeps GCR out away from Earth and low-orbiting satellites like the International Space Station. Finally, the gases of Earth’s atmosphere absorb radiation.

25.10.2021 - 18:48 [ National Aeronautics and Space Administration ]

With NASA Data, Researchers Find Standing Waves at Edge of Earth’s Magnetic Bubble

(Oct.6, 2021)

The latest work considers the waves that form across the entire surface of the magnetosphere, using a combination of models and observations from NASA’s THEMIS mission, Time History of Events and Macroscale Interactions during Substorms.

The researchers found when solar wind pulses strike, the waves that form not only race back and forth between Earth’s magnetic poles and the front of the magnetosphere, but also travel against the solar wind. Archer likened these two kinds of movement to crossing a river: A boat can go from one riverbank to the other (traveling towards the poles) and upstream (against the solar wind). At the front of the magnetosphere, these waves appear to stand still.

25.10.2021 - 17:25 [ Forbes.com ]

Is Earth’s Magnetic Shield Eroding?

(29.3.2018)

The strength of Earth’s main magnetic field is currently about 29.5 microteslas, down 5 microteslas, or 14 percent from its strength three centuries ago.

We know this. There is no question of this.

25.10.2021 - 17:04 [ PRI.org ]

Scientists link Earth‘s magnetic reversals to changes in planet‘s life and climate

(April 19, 2021)

The researchers examined the rings of the tree to look for changes in the amount of carbon-14 over a period of years, Gramling explains. Carbon-14 is useful not only for dating things, but because the interaction of cosmic rays with molecules in the atmosphere produces a lot of it. And when the Earth has a weakened magnetic field, more cosmic rays hit the planet.

The scientists indeed found a large spike in carbon-14 in the tree, which they could then compare with the rock record that indicated a magnetic reversal. (…)

In addition, there is the documented rise in cave art right about 41,000-42,000 years ago, Gramling points out.

04.10.2021 - 07:23 [ Astronomy.com ]

When north goes south: Is Earth‘s magnetic field flipping?

(September 14, 2021)

Something odd is happening to Earth’s magnetic field. Over the last 200 years, it’s been slowly weakening and shifting its magnetic north pole (where a compass points, not to be confused with the geographic north pole) from the Canadian Arctic toward Siba. In recent decades, however, that slow shift south has quickened — reaching speeds upwards of 30 miles per year (48 kilometers per year).

04.10.2021 - 07:04 [ National Astronomical Observatory of Japan / SciTechdaily.com ]

Interplay Between Magnetic Force and Gravity in Massive Star Formation

(September 26, 2021)

The magnetic field is part of one of the four fundamental forces in nature. It plays a vital role in everyday life, from producing electricity in hydroelectric power plants to diagnosing diseases in medicine. Historically, the Earth’s magnetic field served as a compass for travelers before modern technology was available. Crucially for life, the Earth’s magnetic field acts as a shield protecting us from charged particles emanating from the Sun, which are accelerated by the Sun’s magnetic field. Removing this shield would very likely extinguish life on Earth.

04.10.2021 - 05:51 [ Forbes.com ]

Is Earth’s Magnetic Shield Eroding?

(29.3.2018)

The strength of Earth’s main magnetic field is currently about 29.5 microteslas, down 5 microteslas, or 14 percent from its strength three centuries ago.

We know this. There is no question of this.

20.09.2021 - 05:45 [ PRI.org ]

Scientists link Earth‘s magnetic reversals to changes in planet‘s life and climate

(April 19, 2021)

The researchers examined the rings of the tree to look for changes in the amount of carbon-14 over a period of years, Gramling explains. Carbon-14 is useful not only for dating things, but because the interaction of cosmic rays with molecules in the atmosphere produces a lot of it. And when the Earth has a weakened magnetic field, more cosmic rays hit the planet.

The scientists indeed found a large spike in carbon-14 in the tree, which they could then compare with the rock record that indicated a magnetic reversal. (…)

In addition, there is the documented rise in cave art right about 41,000-42,000 years ago, Gramling points out.

10.08.2021 - 10:48 [ PRI.org ]

Scientists link Earth‘s magnetic reversals to changes in planet‘s life and climate

(April 19, 2021)

The researchers examined the rings of the tree to look for changes in the amount of carbon-14 over a period of years, Gramling explains. Carbon-14 is useful not only for dating things, but because the interaction of cosmic rays with molecules in the atmosphere produces a lot of it. And when the Earth has a weakened magnetic field, more cosmic rays hit the planet.

The scientists indeed found a large spike in carbon-14 in the tree, which they could then compare with the rock record that indicated a magnetic reversal. (…)

In addition, there is the documented rise in cave art right about 41,000-42,000 years ago, Gramling points out.

15.07.2021 - 09:24 [ PRI.org ]

Scientists link Earth‘s magnetic reversals to changes in planet‘s life and climate

(April 19, 2021)

The researchers examined the rings of the tree to look for changes in the amount of carbon-14 over a period of years, Gramling explains. Carbon-14 is useful not only for dating things, but because the interaction of cosmic rays with molecules in the atmosphere produces a lot of it. And when the Earth has a weakened magnetic field, more cosmic rays hit the planet.

The scientists indeed found a large spike in carbon-14 in the tree, which they could then compare with the rock record that indicated a magnetic reversal. (…)

In addition, there is the documented rise in cave art right about 41,000-42,000 years ago, Gramling points out.

15.07.2021 - 09:03 [ ScienceAlert.com ]

Earth‘s Magnetic Field Could Be Changing Much Faster Than We Ever Realised

(8 JULY 2020)

Past palaeomagnetic studies have shown that the magnetic field could change direction at up to 1 degree a year, but the latest study suggests that movements of up to 10 degrees annually are possible.

15.07.2021 - 08:54 [ Forbes.com ]

Is Earth’s Magnetic Shield Eroding?

(29.3.2018)

The strength of Earth’s main magnetic field is currently about 29.5 microteslas, down 5 microteslas, or 14 percent from its strength three centuries ago.

We know this. There is no question of this.

15.07.2021 - 08:30 [ University of Maryland / ScienceDaily.com ]

Space mission first to observe key interaction between magnetic fields of Earth and sun

Date: May 12, 2016

Source: University of Maryland

Summary: Physicists have now provided the first major results of NASA‘s Magnetospheric Multiscale (MMS) mission, including an unprecedented look at the interaction between the magnetic fields of Earth and the sun. The article describes the first direct and detailed observation of a phenomenon known as magnetic reconnection, which occurs when two opposing magnetic field lines break and reconnect with each other, releasing massive amounts of energy.

21.02.2021 - 13:05 [ ScienceNews.org ]

50 years ago, scientists named Earth’s magnetic field as a suspect in extinctions

(November 19, 2020)

Effects of Earth’s magnetic field — Science News, November 21, 1970

„Earth’s magnetic field has frequently reversed at intervals of 1 million to 100 million years. A few scientists now suspect that these reversals may have had drastic effects on terrestrial life.… During the past 2.5 million years, eight species of one-cell marine animals called Radiolaria became extinct. Six of these extinctions occurred simultaneously throughout their geographic range immediately following magnetic reversals.“

21.02.2021 - 12:40 [ Science Magazine ]

A global environmental crisis 42,000 years ago

(19.02.2021)

We find that geomagnetic field minima ~42 ka, in combination with Grand Solar Minima, caused substantial changes in atmospheric ozone concentration and circulation, driving synchronous global climate shifts that caused major environmental changes, extinction events, and transformations in the archaeological record.

21.02.2021 - 12:35 [ CNN ]

Reversal of Earth‘s magnetic poles may have triggered Neanderthal extinction — and it could happen again

(19.02.2021)

Some 42,000 years ago, in an event known as the Laschamp Excursion, the poles did just that for around 800 years, before swapping back — but scientists were unsure exactly how or if it impacted the world.

Now, a team of researchers from Sydney‘s University of New South Wales and the South Australian Museum say the flip, along with changing solar winds, could have triggered an array of dramatic climate shifts leading to environmental change and mass extinctions.

21.02.2021 - 03:32 [ NASA.gov ]

NASA Missions Make Unprecedented Map of Sun’s Magnetic Field

They’ll have a chance to take that step forward soon: A re-flight of the mission was just greenlit by NASA. Though the launch date isn’t yet set, the team plans to use the same instrument but with a new technique to measure a much broader swath of the Sun.

“Instead of just measuring the magnetic fields along the very narrow strip, we want to scan it across the target and make a two-dimensional map,” McKenzie said.

15.09.2020 - 21:04 [ NASA ]

NASA, NOAA to Discuss Solar Cycle Prediction During Media Teleconference

Tuesday, 9/15/2020

NASA and the National Oceanic and Atmospheric Administration (NOAA) will discuss predictions for the upcoming solar cycle during a media teleconference at 1 p.m. EDT Tuesday, Sept. 15. Tracking the solar cycle is a key part of better understanding the Sun and mitigating its impacts on human technology and infrastructure.

During the teleconference, experts on the Solar Cycle 25 Prediction Panel will discuss recent updates in solar cycle progress, and the forecast for the upcoming cycle, Solar Cycle 25.

15.09.2020 - 18:01 [ Europäische Weltraumagentur / European Space Agency - ESA.int ]

Secrets for Solar Orbiter to solve

(04.09.2020)

The Sun’s magnetic field is responsible for all the solar activity we see; it drives the 11-year ebb and flow in the number of sunspots, and dominates the behaviour of the solar atmosphere. Furthermore, this magnetic field surrounds the entire solar system, creating a giant bubble known as the heliosphere that is filled with electrified gas known as plasma. Disturbances in this plasma can affect the planets, creating aurorae and interfering with the behaviour of technology. Yet the details of the magnetic field’s initial generation inside the Sun are not yet understood.

09.08.2020 - 08:07 [ journals.plos.org ]

The Earth’s magnetic field in Jerusalem during the Babylonian destruction: A unique reference for field behavior and an anchor for archaeomagnetic dating

Archaeomagnetism, the application of paleomagnetic methods to archaeological materials, is interdisciplinary not only in its methods but also in its impact. Well-dated archaeological materials are a critical data source for geomagnetic secular variation models [1–6], which are used to explore the dynamic structure of Earth’s core [7, 8], the rates of cosmogenic isotope production in the atmosphere [9–11] and the possible effect of geomagnetism on climate [11–13]. Precise documentation of the ancient field also helps contextualize geomagnetic observations from the modern era, such as the evolution of the South Atlantic Anomaly [14, 15] and the ongoing decline in the field’s intensity [16–18].

09.08.2020 - 08:05 [ Haaretz ]

Ruins of Ancient Jerusalem Help Unravel Enigmas of Earth’s Magnetic Field

Albert Einstein once called the behavior of the magnetic field one of the great mysteries of physics, but understanding and possibly predicting its changes has taken on a new urgency for scientists. The field has lost around 10 percent of its strength since measurements began less than 200 years ago, leading some researchers to question whether we are on the way to a flip in polarity, which would be preceded by a loss of our precious shield against cosmic radiation.

28.03.2020 - 15:18 [ CNN ]

Scientists found a secret in old Voyager 2 data. This is why we need to revisit Uranus and Neptune

„The way in which the sun‘s solar wind interacts with Uranus is unlike any planet we‘ve ever explored,“ DiBraccio said. „We are left with questions regarding to what degree the solar wind affects dynamics at Uranus such as transporting atmospheric particles, transferring energy and even changing the planet‘s climate over time.“

22.01.2020 - 22:09 [ Geophysical Research Letters 35(16) / researchgate.net ]

Magnetic effect on CO 2 solubility in seawater: A possible link between geomagnetic field variations and climate

(August 2008)

Correlations between geomagnetic-field and climate parameters have been suggested repeatedly, but possible links are controversially discussed. Here we test if weak (Earth-strength) magnetic fields can affect climatically relevant properties of seawater. We found the solubility of air in seawater to be by 15% lower under reduced magneticfield (20 mT) compared to normal field conditions (50 mT). The magnetic-field effect on CO2 solubility is twice as large, from which we surmise that geomagnetic field variations modulate the carbon exchange between atmosphere and ocean. A 1% reduction in magnetic dipole moment may release up to ten times more CO2 from the surface ocean than is emitted by subaerial volcanism.

02.01.2020 - 14:36 [ National Aeronautics and Space Administration ]

Solar Activity Forecast for Next Decade Favorable for Exploration

(12.06.2019)

The Sun‘s activity rises and falls in an 11-year cycle. The forecast for the next solar cycle says it will be the weakest of the last 200 years. The maximum of this next cycle – measured in terms of sunspot number, a standard measure of solar activity level – could be 30 to 50% lower than the most recent one.

02.01.2020 - 13:40 [ Geophysical Research Letters 35(16) / researchgate.net ]

Magnetic effect on CO 2 solubility in seawater: A possible link between geomagnetic field variations and climate

(August 2008)

Correlations between geomagnetic-field and climate parameters have been suggested repeatedly, but possible links are controversially discussed. Here we test if weak (Earth-strength) magnetic fields can affect climatically relevant properties of seawater. We found the solubility of air in seawater to be by 15% lower under reduced magneticfield (20 mT) compared to normal field conditions (50 mT). The magnetic-field effect on CO2 solubility is twice as large, from which we surmise that geomagnetic field variations modulate the carbon exchange between atmosphere and ocean. A 1% reduction in magnetic dipole moment may release up to ten times more CO2 from the surface ocean than is emitted by subaerial volcanism.

02.01.2020 - 13:40 [ Ludwig Maximilian Universität München ]

Wenn ein Treibhausgas baden geht: Wie das Erdmagnetfeld unser Klima beeinflusst

(6. Oktober 2008)

Die Ergebnisse zeigten, dass selbst kleine Veränderungen des Magnetfelds die Löslichkeit von Gasen im Wasser verändern. „Wenn das Magnetfeld schwächer war, löste sich 15 Prozent weniger Luft im Wasser als bei einem stärkeren Magnetfeld“, erläutert Winklhofer. „Für Kohlendioxid war der beobachtete Effekt sogar doppelt so stark.“

02.01.2020 - 13:39 [ Harvard.edu ]

Magnetic Flux Ropes in the Martian Atmosphere: Global Characteristics

(März 2004)

We report observations of magnetic fields amplitude, which consist of a series of individual spikes in the Martian atmosphere. A minimum variance analysis shows that these spikes form twisted cylindrical filaments. These small diameter magnetic filaments are commonly called magnetic flux ropes. We examine the global characteristics of magnetic flux ropes, which are observed on 5% of the elliptical orbits of Mars Global Surveyor.

02.01.2020 - 13:33 [ European Geosciences Union / Copernikus Gesellschaft ]

MESSENGER Observations of Magnetic Flux Ropes in Mercury’s Plasma Sheet

(2014)

A superposed epoch analysis demonstrates that the magnetic structure of the flux ropes issimilar to what is observed at Earth, but the timescales are 40 times faster at Mercury.

02.01.2020 - 13:24 [ University College London ]

Magnetic Rope observed for the first time between Saturn and the Sun

(06.07.2016)

The Cassini spacecraft has been in orbit around Saturn since 2004, and after many years analyzing the data collected, Cassini has observed the first FTE at Saturn.

02.01.2020 - 13:20 [ ScienceMag.org ]

Magnetic Reconnection in the Near Venusian Magnetotail

(04.05.2012)

Observations with the Venus Express magnetometer and low-energy particle detector revealed magnetic field and plasma behavior in the near-Venus wake that is symptomatic of magnetic reconnection, a process that occurs in Earth’s magnetotail but is not expected in the magnetotail of a nonmagnetized planet such as Venus.

02.01.2020 - 13:18 [ National Aeronautics and Space Administration ]

Magnetic Portals Connect Earth to the Sun

(30.10.2008)

„It‘s called a flux transfer event or ‚FTE,'“ says space physicist David Sibeck of the Goddard Space Flight Center. „Ten years ago I was pretty sure they didn‘t exist, but now the evidence is incontrovertible.“

Indeed, today Sibeck is telling an international assembly of space physicists at the 2008 Plasma Workshop in Huntsville, Alabama, that FTEs are not just common, but possibly twice as common as anyone had ever imagined.