Questions tagged [magnetic-field]

Questions regarding magnetic fields.

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42
votes
2answers
3k views

Why has Venus's atmosphere not been stripped away by solar wind?

This answer on Space Exploration to a question about Mars says that one reason Mars has such a thin atmosphere is because it lacks a magnetic field to protect it from the effect of double solar winds. ...
29
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1answer
3k views

Can a tectonically inactive planet retain a long-term atmosphere?

Can a planet be tectonically inactive and still retain a magnetosphere and protected atmosphere? How does that work? How else could a planet retain a thick atmosphere like Earth's for extensive ...
23
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2answers
26k views

Why did Venus not lose its atmosphere without magnetic field?

It is often stated that the magnetosphere not only shields the planet from cosmic radiation, but also prevents atmospheric loss. Why then did Venus not lose most of its atmosphere if it doesn't have a ...
20
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3answers
6k views

Can a magnetic field of an object be stronger than its gravity?

Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?
20
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1answer
850 views

Why Did Mars lose its Magnetic Field?

I had heard that Mars once had a planetary magnetic field, but that it is now gone? What happened to it?
15
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1answer
373 views

Magnetic fields of peculiar HgMn A type stars

Do HgMn (peculiar A type) stars really possess global magnetic fields? See, for example, this paper by Hubrig et al. from 2012.
14
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2answers
857 views

What Causes the Large Radiation Fields Around Jupiter?

I had heard that the large radiation belts around Jupiter may be formed by liquid metallic hydrogen in (or around) Jupiter's core (which Wikipedia says haven't been observed in labs yet due to the ...
14
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1answer
386 views

Were effects of a planetary magnetic field reversal observed on other planets than Earth?

From geological records in rocks and minerals we know that the magnetic field of Earth changed its polarity multiple times in the history. See Geomagnetic reversal. Was a similar process of a ...
12
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1answer
242 views

How can only 1 magnetic pole of the Sun change at a time?

I read some news stories about the current Solar maximum and the flipping of the magnetic poles. They say that one of the magnetic poles has switched polarity and the other will switch in about a ...
10
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1answer
3k views

Does the Moon's magnetic field affect Earth's magnetic field?

I wanted to ask a question; it's simple but I cannot find any possible and perfect solution. Earth has poles, North and South. By which we can get directions using a compass or a needle compass, but ...
9
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4answers
3k views

Can magnetism escape a black hole?

I know light, and practically nothing but gravity can escape a black hole. My question is: can magnetism escape a black hole? A couple things that convince me it can are: Jupiter's magnetic field ...
9
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1answer
440 views

Will the Sun rotate slower in red giant form?

When the Sun runs out of hydrogen to fuse it will grow bigger in size and my question is does it rotate more slowly, like a spinning ice skater extending their arms to reduce angular velocity? What ...
7
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2answers
202 views

Why is the Earth's magnetic field stronger than its neighbors?

[Edited] I've learned that the Earth's core is hot due to decay of radioactive elements, causing the liquid part of the core to stay liquid. This was stated as an explanation to why the Earth has a ...
7
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1answer
401 views

Is there a strong galactic magnetic field?

My main question is: Is there a strong galactic magnetic field, perhaps driven by the supermassive black hole at the center of our galaxy? I am also wondering if this field would be strong enough to ...
6
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2answers
528 views

Magnetars and the Dynamo Effect

How do magnetars create/sustain such strong magnetic fields? If a dynamo effect did create a magnetar, then what creates the magnetic field? The dynamo effect requires an electrically conductive fluid,...
6
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1answer
362 views

Earth and ferromagnetism [closed]

Earth's core is a giant liquid iron ball actually. If I know well, the magnetic field of our planet (that protects the surface from some particles comes from the Sun) can exist because as Earth ...
6
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1answer
109 views

What forces expelled these huge clouds, then blocked further progress, yet allowed it to maintain its threads?

From Wikipedia and NASA: Caption: NASA: S74-15583 (July 1973) --- A huge solar eruption can be seen in this Spectroheliogram obtained during the Skylab 3 mission by the Extreme Ultraviolet ...
6
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1answer
162 views

Are sunspots vertically displaced from the surrounding photospheric plasma?

While reading a paper on the helioseismology of sunspots (Cameron, et al.), very brief reference is made to the "vertical displacement of a blob of plasma." This caused me to wonder if the emissive ...
6
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1answer
174 views

Anti matter in Jupiter magnetic field?

My question is based in this Wikipedia article about the Jupiter magnetic field: https://en.wikipedia.org/wiki/Magnetosphere_of_Jupiter Jupiter magnetic field generates plasma and accelerates ionized ...
6
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1answer
111 views

Do the magnetic fields of stars and/or other planets reverse?

I've heard of the magnetic field of the earth reversing poles over the course of thousands of years but do stars and other planets (specifically gas giants) also experience this? If so how does it ...
6
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1answer
412 views

How does an accreting black hole acquire magnetic fields?

There is actually a similar question on this site: Can magnetism escape a black hole?, however the answers do not focus on accretion, which is my main concern, so I start a new one. In Kip Thorne's ...
6
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1answer
119 views

Do magnetic fields affect planetary rings?

Planetary rings seem to generally form on the ecliptic plane because of the rotation of the planet, but I was wondering what kind of effect the magnetic field of the planet might have on the ring ...
6
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1answer
175 views

Are there collected data about the direction of rotation of black holes and the direction of the magnetic field?

Is there a relation between the direction of rotation of black holes or neutron stars and the magnetic dipole moment of BH or neutron stars? BTW, are there different directions of this two parameters ...
6
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2answers
190 views

Does the shape of a supernova remnant depend on the progenitor star's magnetic field?

The magnetic field activity in a star can be very chaotic and my question is are they somehow related?
5
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1answer
252 views

Roche Zone of a black hole vs Roche Zone of Neutron Star

Suppose a very unusually small back hole with the mass of about, lets say, 1.5 solar masses(hawking radiation should destroy a lot of mass let's assume). It thus would have a Roche limit smaller than ...
5
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1answer
304 views

Why are the magnetic poles of a pulsar so far off the rotational axis, yet stable?

My understanding is that a pulsar is a neutron star whose magnetic poles don't coincide with the rotational poles and whose magnetic poles sweep through Earth (allowing us to hear radio noise). If we ...
5
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2answers
325 views

How much magnetic attraction is there between the Sun and Earth?

How much magnetism is there between the Earth and Sun? Would the distance from the Sun differ for not the Earth iron core and how much?
5
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1answer
138 views

Do narrow lines in the spectra of O- and B- type stars always indicate magnetic fields?

I was reading a paper on the differential emission measures of a set of hot O- and B- type stars. As the authors discuss in Section 3 (page 959), two stars, $\tau$ Sco and $\theta^1$ Ori C, have ...
4
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1answer
73 views

Is it possible to tell if a certain extrasolar planet produces its own magnetic field?

I know by observing the dimness of a star it is possible to calculate an exoplanet's distance from the star and its mass by how much the star wobbles. However, is there any way to accurately determine ...
4
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1answer
69 views

Why does the solar wind switch to flowing straight by the time it reaches Earth?

Between 02:01 and 02:29 the new NASA Goddard video 5 New Discoveries from NASA's Parker Solar Probe explains finding # 4, A ...
4
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1answer
723 views

What will New Horizons be able to say about a magnetic field at Pluto?

Does NASA's New Horizons flyby probe to Pluto have instruments to measure Pluto's (or Charon's) magnetic field, if any? I'm a bit confused by the Wikipedia article which says that New Horizons, ...
4
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1answer
77 views

How is it determined that the X-ray and radio intensity come from a magnetic field bridge between two clusters of galaxies?

Gizmodo's Astronomers Spot Mysterious, 10-Million-Light-Year-Long Magnetic Field Connecting Two Galaxy Clusters shows the image below, and Space.com's A Weird 'Radio Bridge' 10 Million-Light Years ...
4
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1answer
522 views

Does a magnet outside a black hole affect one inside it?

If I had 2 really strong magnets, and I threw one into a black hole, while holding one outisde it at a safe distance, what would happen? Would the magnets affect each other in any way? Would one push/...
4
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1answer
85 views

Why is the magnetic reconnection(of sun) effect many orders of magnitude faster than predicted by standard models?

Why is the sun's magnetic reconnection effect many orders of magnitude faster than predicted by standard models?
4
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2answers
128 views

What triggers solar flares?

The sun is a big ball of hot plasma which contains free electrons. However, how does the absence of metallic elements in the sun generate the magnetic field to orchestrate these free electrons to ...
4
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0answers
53 views

Cause of ~10 minute Oscillations in Low Energy Electron Flux in Earth's Magnetosphere

I am analyzing data from an instrument that measures low energy electron flux at Geo-Stationary orbit. There are sharp oscillations in the particle flux of 30 eV electrons occurring from about noon ...
3
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1answer
110 views

Earth's magnetic field vs. refrigerator magnet

According to this article: The Earth's field ranges between approximately 25,000 and 65,000 nT (0.25–0.65 G). By comparison, a strong refrigerator magnet has a field of about 10,000,000 ...
3
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2answers
255 views

If the moon still had a magnetic field how long would have been possible to keep an atmosphere?

Let's assume the Moon had a considerable magnetic field to prevent the atmosphere dispersion caused by solar wind. Given the low gravity of the Moon, how many years would pass before all the gases (of ...
3
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2answers
116 views

Are magnetic field lines Spiral for Spiral Galaxies? If no, then how it look like topologically?

I am an undergraduate doing summer project at USO. I am working on Sun's Magnetic field model. I got spiral graph for that, which looks like any spiral Galaxy. Do you think that there is some ...
3
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3answers
4k views

Do planets repel?

I know gravity is the result of mass. Gravity is nothing but the attractive force on a body due to its mass. I have a question that may be silly. In magnetism we have attraction and repulsion. Earth ...
3
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1answer
233 views

What causes Titan a moon to have a denser atmosphere than that of a Mars?

I'm wondering about Mars and Titan. If Mars is larger than Titan how come it lost most of its atmosphere? Mars also has a magnetic field while Titan doesn't. Yet Titans atmospheric pressure on the ...
3
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3answers
228 views

Will the Sun's solar wind push a permanent magnet out of our solar system?

If you were place a strong permanent magnet into the solar wind, like a 1 inch cube neodymium magnet, would the charged particles of the solar wind colliding with the magnet's magnetic field push the ...
3
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1answer
91 views

What exactly are infrared dark clouds and what is the significance of the orientation of their magnetic fields?

In the video Why NASA's SOFIA Telescope On A Plane is "Perfectly Balanced" after about 10:04 SOFIA associate director James Jackson says: We have a spectrometer ...
3
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1answer
78 views

Brown dwarf magnetic activity

I have not been able to find an answer to my question through google, and therefore ask it on this medium. Do brown dwarfs have spots and faculae similar to other heavier stars?
3
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1answer
125 views

Would the heliosphere disappears if our sun becomes a white dwarf?

Just curious I like to know if one fine day our Sun turns into a white dwarf at the later stage of its life, would the magnetic bubble, heliosphere gets thinner and eventually disappear? also at this ...
3
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1answer
1k views

What exactly is this VLA radio image of Jupiter showing?

This VLA image is beautiful, and instructive, but I don't understand it fully. This version is from an article in Gizmodo where the credit reads: A radio image of Jupiter captured by the Very Large ...
3
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2answers
178 views

Is there a way to know how the magnetic field was at the very beginning of our universe?

I recently read that Gamma-ray bursts are catastrophic events, related to the explosion of massive stars 50 times the size of our sun. If you ranked all the explosions in the universe based on ...
3
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1answer
57 views

Ground Induced Currents on Mars

Since Mars is only weakly magnetized does Mars not suffer from ground induced currents or are they far worse than on Earth?
3
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0answers
20 views

Superconducting space dust; what transient fields could induce persistent current loops?

Science Alert's Superconductivity Has Been Discovered in Meteorites For The First Time quotes from Superconductivity found in meteorites (Wampler et al. PNAS March 23, 2020) The paper describes the ...
2
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3answers
416 views

What could possibly save an atmosphere other than a magnetic field? Why can't a magnetic field save the atmosphere in certain cases?

Similar question here. We know as a fact that the magnetic field protects planets from Solar Wind, a damaging, continuous, atmosphere-stripping wind of charged ions. Thus, a magnetic field protected ...