Archive for the ‘Electro-magnetism’ Category

.
.
Quote: ‘STEVE is a recently identified atmospheric phenomenon caused by supersonic plasma jets flowing at altitudes >100 km.’ Scientists continue to wrestle with its electromagnetic mysteries.

Spaceweather.com

Nov. 22, 2020: Just when you thought STEVE couldn’t get any weirder. A new paper published in the journal AGU Advances reveals that the luminous purple ribbon we call “STEVE” is often accompanied by green cannonballs of light that streak through the atmosphere at 1000 mph.

“Citizen scientists have been photographing these green streaks for years,” says Joshua Semeter of Boston University, lead author of the study. “Now we’re beginning to understand what they are.”

STEVE is a recent discovery. It looks like an aurora, but it is not. The purple glow is caused by hot (3000 °C) rivers of gas flowing through Earth’s magnetosphere faster than 13,000 mph. This distinguishes it from auroras, which are ignited by energetic particles raining down from space. Canadian aurora watchers first called attention to the phenomenon about 10 years ago, whimsically naming it STEVE; researchers have been studying it ever since.

View original post 398 more words

Image credit: Elfiehall @ Wikipedia


More unexplained goings-on as the solar wind’s charged particles reach Earth’s ionosphere. For the latest photos showing bright green light, see the source article here.
– – –
The purple-and-green, atmospheric light show nicknamed STEVE just got even stranger, says Science News.

STEVE, short for Strong Thermal Emission Velocity Enhancement, is a sky glow that appears south of the northern lights (SN: 3/15/18).

STEVE’s main feature is a mauve band of light formed by a stream of plasma flowing westward through the atmosphere — a different phenomenon from the one that gives rise to auroras (SN: 4/30/19).

But STEVE’s purple arc is often accompanied by a “picket fence” of vertical green stripes.

(more…)

.
.
Scientists report electric fields naturally occurring in the comet’s atmosphere in connection with its auroras. NASA calls them electromagnetic emissions.

Spaceweather.com

Sept. 22, 2020: Imagine putting your thumb on a garden hose and sending a jet of water into the sky. At the apex of the stream, auroras form. It turns out, some comets can actually perform this trick.

In a paper published this week in Nature Astronomy, researchers described how comet 67P/Churyumov-Gerasimenko turns vaporous jets of water into auroras.

The European Space Agency’s Rosetta spacecraft observed the weird lights while it was orbiting Comet 67P in 2014-2016. At first researchers misunderstood what the glow was. It couldn’t be an aurora, could it? For one thing, the comet doesn’t even have a magnetic field–a key ingredient of geomagnetic storms. Also, the lights of Comet 67P are invisible to the human eye. They shine at far ultraviolet wavelengths, unlike the familiar red and green curtains that dance around Earth’s poles.

“Nevertheless, they are auroras,” says Marina Galand of Imperial College London…

View original post 267 more words

This twitter video caught my eye last night, it was taken near Miami a few nights ago. It shows mysterious lights, confirmed from many sources and featured on national US TV channels where it’s reported answers are being demanded from the Pentagon.

Then today my physicist friend Mike McCulloch posted a tweet about some similar phenomena which have been observed for many years in Norway.

(more…)

During a total solar eclipse, the Sun’s corona and prominences are visible to the naked eye [image credit: Luc Viatour / https://Lucnix.be ]


There’s an interesting time-series animation of the solar corona here. Clear differences in the corona at solar minimum compared to maximum were observed by the globetrotting researchers.
– – –
While the world has been dealing with the coronavirus pandemic, researchers at the University of Hawaiʻi Institute for Astronomy (IfA) have been hard at work studying the solar corona, the outermost atmosphere of the sun which expands into interplanetary space, reports Phys.org.

This stream of charged particles radiating from the surface of the sun is called the solar wind and expands to fill the entire solar system.

The properties of the solar corona are a consequence of the sun’s complex magnetic field, which is produced in the solar interior and extends outward.

A new study by IfA graduate student Benjamin Boe, published Wednesday, June 3rd in the Astrophysical Journal, used total solar eclipse observations to measure the shape of the coronal magnetic field with higher spatial resolution and over a larger area than ever before.

(more…)

.
.
Interesting: ‘Over the last 200 years, the globally averaged magnetic field has lost around 9% of its strength, with the South Atlantic Anomaly leading the way.’

Spaceweather.com

May 26, 2020: New data from Europe’s Swarm satellites show something strange is afoot in Earth’s magnetic field. The South Atlantic Anomaly might be splitting in two. “A new, eastern minimum of the South Atlantic Anomaly has appeared over the last decade,” says Jürgen Matzka, from the German Research Center for Geosciences. “In recent years it has been developing vigorously.”

splash1Above: Development of the South Atlantic Anomaly from 2014 to 2020. Credit: ESA/Swarm. [more] The South Atlantic Anomaly is a weak spot in Earth’s magnetic field centered roughly on the Atlantic side of South America. Discovered in 1958, it has been growing and shifting for decades. The latest data from Swarm show a new weak spot forming just off the southern tip of Africa.

“We are very lucky to have the Swarm satellites in orbit to investigate this development,” says Matzka.

Launched in November 2013, Swarm is a…

View original post 298 more words


It now seems all planetary bodies can have magnetospheres, whether or not they have a significant magnetic field. This would also help to explain why Venus, with hardly any ‘protective’ magnetic field, has a much thicker atmosphere than Earth. Wikipedia might need an update.
– – –
Five years after NASA’s MAVEN spacecraft entered into orbit around Mars, data from the mission has led to the creation of a map of electric current systems in the Martian atmosphere, reports Phys.org.

“These currents play a fundamental role in the atmospheric loss that transformed Mars from a world that could have supported life into an inhospitable desert,” said experimental physicist Robin Ramstad of the University of Colorado, Boulder.

“We are now currently working on using the currents to determine the precise amount of energy that is drawn from the solar wind and powers atmospheric escape.” Ramstad is lead author of a paper on this research published May 25 in Nature Astronomy.

(more…)

Credit: NASA


This BBC link includes a video which shows the weakening of the magnetic field over the last 400 years (under ‘Magnetic flip’ sub-heading).
– – –
In an area stretching from Africa to South America, Earth’s magnetic field is gradually weakening, says Phys.org.

This strange behaviour has geophysicists puzzled and is causing technical disturbances in satellites orbiting Earth.

Scientists are using data from ESA’s Swarm constellation to improve our understanding of this area known as the ‘South Atlantic Anomaly.’

(more…)

Browsing twitter recently I ran across this short video of a solar flare shot a few days ago.

After asking for some clarification on frame rate I was really intrigued.

(more…)

An end to this?


The researchers also imagine devices that would wirelessly power implants in a patient’s body without any surgery to change batteries.

Any device that sends out a Wi-Fi signal also emits terahertz waves —electromagnetic waves with a frequency somewhere between microwaves and infrared light, says Technology.org.

These high-frequency radiation waves, known as “T-rays,” are also produced by almost anything that registers a temperature, including our own bodies and the inanimate objects around us.

Terahertz waves are pervasive in our daily lives, and if harnessed, their concentrated power could potentially serve as an alternate energy source. Imagine, for instance, a cellphone add-on that passively soaks up ambient T-rays and uses their energy to charge your phone.

However, to date, terahertz waves are wasted energy, as there has been no practical way to capture and convert them into any usable form.

(more…)

.
.
Includes a beginner’s guide to the various types of sprite now known to occur.

Spaceweather.com

March 7, 2020: Sprite season is coming. Spring thunderstorms often produce the year’s first big bursts of upward-directed lightning. To get ready, Puerto Rican sprite chaser Frankie Lucena has prepared a chart to identify the different forms, including a newly-discovered type of sprite called “the Ghost.”

Frankie-Lucena-TLE_Chart_2020_1200dpi_1583176434

“This chart provides just a glimpse of what can be seen and photographed above very strong thunderstorms,” says Lucena. “I used actual images, enhanced and slightly modified to better show what they actually look like.”

“This is the first chart to show the Ghost and a Negative Sprite event,” he continues. “The Ghost is a green colored shadow that appears above some sprites. The green color is caused by electrons exciting oxygen molecules in the mesosphere, approximately 80 km high. A Negative Sprite is triggered by a -CG lightning discharge as opposed to a regular sprite which is triggered by a +CG lightning discharge.”…

View original post 639 more words

Mars from NASA’s Hubble Space Telescope


Tales of the unexpected on Mars: ‘Day-night fluctuations and things that pulse in the dark’, and other mysteries. What’s unique to Mars?

New data gleaned from the magnetic sensor aboard NASA’s InSight spacecraft is offering an unprecedented close-up of magnetic fields on Mars, says Phys.org.

“One of the big unknowns from previous satellite missions was what the magnetization looked like over small areas,” said lead author Catherine Johnson, a professor at the University of British Columbia and senior scientist at the Planetary Science Institute.

“By placing the first magnetic sensor at the surface, we have gained valuable new clues about the interior structure and upper atmosphere of Mars that will help us understand how it – and other planets like it – formed.”

(more…)

.
.
Something happening in the “ignorosphere”.

Spaceweather.com

Jan. 29, 2020: A new type of aurora is rippling across Arctic skies. Citizen scientists who discovered it nicknamed it “The Dunes” because of its resemblance to desert sand dunes. A paper published in the Jan. 28th issue of AGU Advances describes the new form and the unexpected physics that causes it.

864572_1_unknown_upload_7036138_q0m4d8_1573153212Above: Aurora dunes over Laitila, Finland, on Oct. 7, 2018. Credit: Pirjo Koski. [more] Dune-shaped auroras form in a narrow altitude range 80 km to 120 km above Earth’s surface. Turns out, this is an extremely hard-to-study layer of Earth’s atmosphere. It’s too high for weather balloons, and too low for rockets.

“Due to the difficulties in measuring atmospheric phenomena between 80 and 120 km, we sometimes call this region ‘the ignorosphere‘,” says Minna Palmroth, Professor of Computational Space Physics at the University of Helsinki and the lead author of the study.

Sky watchers in…

View original post 254 more words

The article also explains why ‘understanding forced reconnection can help modelers better predict when disruptive high-energy charged particles might come speeding at Earth.’

NASA’s Solar Dynamics Observatory has observed a magnetic explosion the likes of which have never been seen before, reports Phys.org.

In the scorching upper reaches of the Sun’s atmosphere, a prominence—a large loop of material launched by an eruption on the solar surface—started falling back to the surface of the Sun.

But before it could make it, the prominence ran into a snarl of magnetic field lines, sparking a magnetic explosion.

(more…)

How to Shape a Spiral Galaxy

Posted: December 10, 2019 by oldbrew in Astrophysics, Electro-magnetism, Gravity, research

Spiral galaxy NGC 5457 aka the Pinwheel Galaxy [image credit: European Space Agency & NASA]


No mention of electricity here, although it’s required to create the magnetism: ‘The magnetic behavior of a material depends on its structure, particularly its electron configuration’ – Wikipedia. We’re told these electromagnetic forces stretch for 24,000 light years in one galaxy, but understanding them is still in its infancy.

New observations from SOFIA are shedding light on how spiral-shaped galaxies, like our own Milky Way, get their iconic shape, says NASA.

Our Milky Way galaxy has an elegant spiral shape with long arms filled with stars, but exactly how it took this form has long puzzled scientists. New observations of another galaxy are shedding light on how spiral-shaped galaxies like our own get their iconic shape.

Magnetic fields play a strong role in shaping these galaxies, according to research from the Stratospheric Observatory for Infrared Astronomy, or SOFIA.

(more…)


The two Voyager space probes, launched in 1977, are still delivering tales of the unexpected.

The boundary region between the sun’s sphere of influence and the broader Milky Way galaxy is complicated indeed.

Humanity’s second taste of interstellar space may have raised more questions than it answered, writes Mike Wall @ Space.com.

NASA’s Voyager 2 spacecraft popped free of the heliosphere — the huge bubble of charged particles that the sun blows around itself — on Nov. 5, 2018, more than six years after the probe’s pioneering twin, Voyager 1, did the same.

The mission team has now had some time to take stock of Voyager 2’s exit, which occurred in the heliosphere’s southern hemisphere (as opposed to Voyager 1, which departed in the northern hemisphere).

In a series of five papers published online today (Nov. 4) in the journal Nature Astronomy, the researchers reported the measurements made by the probe as it entered interstellar space.

(more…)

Sunspots [image credit: NASA]


Here it’s claimed that the model matches the observations, which is surely a good start in any research. With a deep solar minimum now in progress, theorists should have plenty of new data to work with.

For 400 years people have tracked sunspots, the dark patches that appear for weeks at a time on the sun’s surface, says Phys.org.

They have observed but been unable to explain why the number of spots peaks every 11 years.

A University of Washington study published this month in the journal Physics of Plasmas proposes a model of plasma motion that would explain the 11-year sunspot cycle and several other previously mysterious properties of the sun.

“Our model is completely different from a normal picture of the sun,” said first author Thomas Jarboe, a UW professor of aeronautics and astronautics. “I really think we’re the first people that are telling you the nature and source of solar magnetic phenomena—how the sun works.”

(more…)

The Return of STEVE

Posted: September 6, 2019 by oldbrew in Electro-magnetism, solar system dynamics

.
.
Introducing ‘STEVE and the green pickets’. This summer, researchers confirmed that STEVE is not an aurora, but is instead a unique phenomenon.

Spaceweather.com

Sept. 5, 2019: Sky watchers are still sorting out all the things they saw during last weekend’s Labor Day geomagnetic storm.  Upon further review, not every light in the sky was the aurora borealis. There was also STEVE:

“Look at the mauve-colored plume. That’s STEVE,” says Alan Dyer, who took the picture at the Saskatchewan Summer Star Party on Aug. 31st. “We saw STEVE two nights in a row from our area in western Canada.”

STEVE (Strong Thermal Emission Velocity Enhancement) looks like an aurora, but it is not. The phenomenon is caused by hot (3000°C) ribbons of gas flowing through Earth’s magnetosphere at speeds exceeding 6 km/s (13,000 mph). These ribbons appear during some geomagnetic storms, revealing themselves by their soft purple glow.

Earlier this year, researchers led by Toshi Nishimura of Boston University published an important paper about STEVE. Using data from NASA’s THEMIS spacecraft, they…

View original post 293 more words

.
.
More electromagnetic goings-on near Earth’s outer fringes.

Spaceweather.com

August 9, 2019: Astronauts are surrounded by danger: hard vacuum, solar flares, cosmic rays. Researchers from UCLA have just added a new item to the list. Earth itself.

“A natural particle accelerator only 40,000 miles above Earth’s surface is producing ‘killer electrons’ moving close to the speed of light,” says Terry Liu, a newly-minted PhD who studied the phenomenon as part of his thesis with UCLA Prof. Vassilis Angelopoulos.

This means that astronauts leaving Earth for Mars could be peppered by radiation coming at them from behind–from the direction of their own home planet.

earthrise_crop

NASA’s THEMIS spacecraft ran across the particles in 2008 not far from the place where the solar wind slams into Earth’s magnetic field. Researchers have long known that shock waves at that location could accelerate particles to high energies–but not this high. The particles coming out of the Earth-solar wind interface have energies up to 100,000…

View original post 212 more words

Credit: thinglink.com


The world contains more fresh water than previously thought. It’s a question of looking in the right places, as this study explains.

In a new survey of the sub-seafloor off the U.S. Northeast coast, scientists have made a surprising discovery: a gigantic aquifer of relatively fresh water trapped in porous sediments lying below the salty ocean.

It appears to be the largest such formation yet found in the world, reports Phys.org.

The aquifer stretches from the shore at least from Massachusetts to New Jersey, extending more or less continuously out about 50 miles to the edge of the continental shelf. If found on the surface, it would create a lake covering some 15,000 square miles.

The study suggests that such aquifers probably lie off many other coasts worldwide, and could provide desperately needed water for arid areas that are now in danger of running out.

(more…)