Mercury hides a monster impact

By Phil Plait | May 3, 2009 8:00 am

How the heck do you hide a terrifyingly huge impact basin easily big enough to stretch from San Francisco to Los Angeles?

Easy. Put it on Mercury.

This new MESSENGER image of Mercury was taken when the spacecraft swept past the tiny planet back in October 2008. The big circular feature is the Rembrandt impact basin, which is a ginormous 715 kilometers (440 miles) across. Incredibly, this feature has never been seen before on Mercury! That goes to show you how hard it’s been to study the planet in the past. From Earth, Mercury never gets very high above the horizon so it’s always a fuzzy blob, and previous spacecraft encounters only imaged parts of the planet.

Head-on view of Rembrandt
Rembrandt seen head-on. Colorado
would comfortably fit inside it.

Plus, sometimes it’s hard to see something that’s really big. I remember standing on the lip of a volcano with a caldera 5 km across, and it was so huge it was hard to tell it was a volcano! In the case of the Rembrandt basin, its location on Mercury, its size, and its somewhat subtle rim made it difficult to see in the past. MESSENGER’s phenomenal cameras, however, were able to catch it in a mosaic of several images.

It looks like a relatively young feature given how well-preserved it looks. Yet it still has plenty of craters in it, indicating it’s been around a while at least. Note the inner circle, too: that’s a common feature in huge impact basins like this, and the reasons the multiple rings form is still being debated.

Rembrandt is cut by a 1000-km-long scarp on the left — the longest yet seen on Mercury — and also has a series of ridges and troughs in the floor unlike anything seen on Mercury or any other planet. Those are somehow causes by crustal deformation, but the specific mechanism isn’t understood yet.

Imagine! Here is an entire planet, one of the closer ones in the solar system, and yet it still holds many mysteries… including some so big they are almost literally right in our face, just waiting to be unveiled and understood. What will MESSENGER see in September, on its third pass of the planet? What will it see once it settles into orbit in March 2011?

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Smithsonian Institution/Carnegie Institution of Washington

CATEGORIZED UNDER: Astronomy, Cool stuff, Pretty pictures

Comments (80)


    That is one big impact mark!

  2. gss_000

    The amount we’re getting from the flybys are really impressive. Not only has it found info on the surface, but also the planet’s magnetic field and the solar wind’s effect:

  3. twobyfour

    Funny thing about these impacts… they are all circular. What are the chances of impact bodies all coming at a perpendicular direction? There is no atmosphere on Mercury to somehow drag, reorient and cushion the impact vector.

    I think we are looking at something else, not impacts.

  4. StevoR

    Awesome! Congrats MESSENGER team – that’s one cool (well okay *HOT*) crater! 8)

    Hmm .. The last Mercurian fly-by was a while ago & they still finding – or is it just releasing – stuff like this?

    Out of curiousity, why wasn’t this announced earlier?

  5. BTW. BA did you see the article by Ken Croswell linked to my name here that shows Mercury may pose a danger to Earth because its orbit could become highly eccentric and unstable?

    You may of course have already posted on this before & I just missed it…

    Also I recall reading in the British-based ‘Astronomy Now’ magazine (August 2005 issue, Page71, article by David Hawksett, one of ten big mysteries of the Solar System) that Arecibo RADAR observations indicated the possibility of a giant volcano on Mercury – could this be the RADAR anomaly that Arecibo saw? Could it be linked with volcanism?

  6. PS. ‘Death from the Skies’ is now available at my library – Blackwood Adelaide hills suburb, South Australia! 😉 :-)

  7. That’s Page 71 (Astronomy Now, August 2005, ‘Mystery (6)”Are there giant volcanoes on Mercury?” by David Hawksett’) with a space between the page & the 71 & please, BA, please, please, please, can we get an editing or even just preveiwing facility here?

    Pretty please with Eta Carinae going supernova on top? It would make an already marvellous blog just so much better!

  8. Is it just an artifact of the image processing, or is the one side of the basin (to the right in the second picture) significantly higher and more rugged than the other? Seems like the walls of crater are still heavily in shadow, as if there were some pretty steep slopes there.

    Cool! I mean, hot! (Stealing SteveO’s joke.)

  9. StevoRaine

    No worries although its S-t-e-v-o-R

  10. Elizabeth

    Actually, that face on image looks to be a composite of two images. If you look very carefully, the left side has the lighting coming from the left. But the right ~1/4, the lighting is coming from the right. The overlap area therefore seems to be anomalous.

  11. I am really looking forward to seeing the wonderful viatas in 2011. It may be a lifeless world, but oh boy does it have some cool features!

  12. Astroquoter

    I’m sure someone could put

    “Rembrandt’s inner circle”

    to good poetic use as a Sf or non-fiction title, caption or chapter heading. Or whatever. :-)

    Wonder if there’s any cinnabar (Mercury ore) on Mercury somewhere?

    Mercury strikes me as the quicksilver planet, the default planet (no moons, no rings, no atmosphere, just planet) and as well pretty astounding.

    It also make sme wonder what Gliese 581 e will be like … An even hotter and closer new found planet, just twice earth-mass. :-)

  13. Appy-polly-loggies, StevoR. Bit dyslexic this morn.

  14. Chris

    On the left 2/3 of the picture, the light is coming from the left. On the right 1/3 it is coming from the right. What’s that about?

  15. @ elizabeth:

    Right you are! Not only am I dyslexic, but woefully inattentive! Going back to bed now….

  16. Astroquoter

    Allusions to Mercury

    Quicksilver Planet

    The Wandering Star which Copernicus never saw (according to legend?)

    The Big Sun World (Asimov)

    The Default Planet (see earlier post)

    Einstein’s Proof (Mercury’s orbital motion defied explanation under Newtionian phyiscs but its precession was neatly explaind by Einstein’s relativity)

    The Iron-Heated Planet

    The World of Greatest Extremes (Its range of temperature is highest -hottest and coldest -venus overallbeing hotter but constant)

    Innermost Planet

    Densest Planet

    Hermes (Arthur C. Clarke, I think, used this in the ‘Rama ‘novels?)

    [Would a community living on Mercury be Hermetic-ally sealed?] 😉

    The Sun Burnt Planet (Aussies’ll get this! ) 😉

    The Sun’s Moon

    The Lesser Evening & Morning Star

  17. StevoRaine

    ___ *Innermost, Densest , Hottest of all *___
    By Steven C.Raine

    Basalt over lava laid
    Mercury a world ablaze!
    In fire formed
    It’s first to die
    When our Day Star goes awry!

    Mercury its hard to see
    Quicksilver twilight speedily
    Over horizons’
    Globe so small
    Curved large Moon
    Yet not at all

    All these things this planet be
    Still it has its mystery!

    (Yes the mysteries are plural but that wouldn’t rhyme.)

    If anyone wishes to use this elesewhere feel free. Just cite the source.
    Feeling mercurial awed & now tired tonight. 😉

  18. StevoRaine

    @ Kuhnigget

    No probs. Apologies accepted – I’m pretty lousy with names & typos & getting things mixed up myself & quite understand. :-)

    a.k.a. StevoR (& a few other tags here as well.)

  19. Astroquoter


    Relativity’s Proof / Einstein’s Proof

    (Mercury’s orbital motion defied explanation under Newtionian phyiscs but its precession was neatly explaind by Einstein’s relativity)

    I meant Newtonean (Newtonian?) physics NOT Newt*i*onian phyiscs whatever that is! 😉 Typos. *Sigh*

  20. Amazing discoveries! I’m always struck how these dead lifeless worlds resemble the Genesis Moon in Star Trek II!

    (Sorry, I could not help myself!)

  21. twobyfour, the angle of impact doesn’t play that much of a role in the shape of the crater. Even a 45 degree angle impact creates a circular crater; the shock wave expands in a circle.

  22. Why does Mercury “never [get] very high above the horizon?” Obviously it’s always fairly close to the sun so it wouldn’t get very high above the horizon at night but that still shouldn’t be an issue for, say, Hubble.

  23. IVAN3MAN

    Phil Plait:

    How the heck do you hide a terrifyingly huge impact basin easily big enough to stretch from San Francisco to Los Angeles?

    Well, this is how the Rembrandt impact basin would appear superimposed on the east coast of the U.S.A., with the central crater positioned north of New Jersey:

    Rembrandt impact basin superimposed on the east coast of the U.S.A.
    Rembrandt impact basin superimposed on the east coast of the U.S.A.
    (Click on the image to enlarge.)

  24. Fluffy, Mercury is too close to the Sun. Hubbles’ sensitive equipment would be damaged by the intensity of the brightness. (I saw this on NG Channel the other night!)

  25. fluffy:

    The only way to remove the Sun’s glare and get a good eyeball on Mercury is to use something to block that glare, like the horizon of the Earth. So, while both heavenly bodies can get very high in the sky, if you want to see Mercury alone your best times come just after sunset or just before sunrise.

    As for Hubble, it has a weakness: it can’t look directly at the Sun.

  26. GJeff

    I’m sorry. I just can’t see the Blessed Virgin Mary in either picture. What am I missing?

  27. clanehin

    OT: Phil, what do you think about the recent accusations against Merck, that they attempted to discredit scientists and published a phony medical journal?

  28. Is it black and white, or is the planet just devoid of color naturally?

  29. twobyfour

    Phil Plait, 45 degrees, correct. But try 22 degrees and under. You get a distinct ovoid shape and almost no rim on the entry side and a compression (e.g. high rim) on the rest side. There ought to be some of these but after peering at different photos of Mercury, I found none. Odd, innit?

  30. Large impact centered on New Jersey? Hmmmmm….

    Nah, too easy.

  31. DrFlimmer

    @ twobyfour

    But since the gravity of mercury (or the moon or whatever else) pulls the object towards its center before it hits, I think that it is unlikely that an object hits very flat. Even a fast object will come in on a parabolic trajectory.

    But, if I may ask, what could cause the craters, if not impacts?

  32. MadScientist

    Pfff. The earth has far larger pits from much larger impacts and it does a better job of hiding them – so much so that there have been wars between geologists claiming to have found yet another large pit and geologists saying they’ve been smoking too much weed. Still pretty amazing that Mercury is being imaged again; the next challenge is to spot the subterranean Mercurians who have been spying on us for millions of years …

    @DrFlimmer: Volcanic eruptions can also cause similar features – but only similar; Gene Shoemaker (and others too) did a lot of work on differentiating between impact craters, calderas, and lava flows.

  33. MadScientist

    @Elizabeth: I don’t know why you think the image is composite and that it’s lit from the left in one and from the right in others. I suspect you haven’t stared much at a gibbous or a quarter moon.

    If you think about the dynamics, what you say isn’t possible. Mercury is tidal-locked so it is only lit from one direction. The spacecraft is moving so you can get images from different angles, but that’s about it – so perhaps it is a composite and you’re seeing some artefacts of viewing from a different angle, but unless there is a god it can’t possibly be lit from a different angle.

  34. SLC

    Re Astroquoter

    Einstein’s Proof (Mercury’s orbital motion defied explanation under Newtionian phyiscs but its precession was neatly explaind by Einstein’s relativity)

    This is a very considerable overstatement. Newtons theory of gravitation, when the perturbation effects of the other planets are included comes up 43 seconds of arc/century short. General relativity accounts for the missing 43 seconds. Actually, the perturbation effects of the other planets account for about 93% of the observed perturbation rate.

  35. IVAN3MAN


    Mercury is tidal-locked so it is only lit from one direction.

    Au contraire, mon ami…

    Mercury — Orbit and Rotation*

    Mercury has the most eccentric orbit of all the planets; its eccentricity is 0.21 with its distance from the Sun ranging from 46 to 70 million kilometers. It takes 88 days to complete an orbit. […] This varying distance to the Sun, combined with a 3:2 spin-orbit resonance of the planet’s rotation around its axis, result in complex variations of the surface temperature.

    “Mercury’s orbit is inclined by 7° to the plane of Earth’s orbit (the ecliptic). [Consequently], transits of Mercury across the face of the Sun can only occur when the planet is crossing the plane of the ecliptic at the time it lies between the Earth and the Sun. This occurs about every seven years on average.

    “Mercury’s axial tilt is almost zero, with the best measured value as low as 0.027°. This is significantly smaller than that of Jupiter, which boasts the second smallest axial tilt of all planets at 3.1 degrees. This means that to an observer at Mercury’s poles the center of the Sun never rises more than 2.1′ above the horizon.

    “At certain points on Mercury’s surface, an observer would be able to see the Sun rise about halfway, then reverse and set before rising again, all within the same
    [Day on Mercury]. This is because approximately four days prior to perihelion, Mercury’s angular orbital velocity exactly equals its angular rotational velocity so that the Sun’s apparent motion ceases; at perihelion, Mercury’s angular orbital velocity then exceeds the angular rotational velocity. Thus, the Sun appears to move in a retrograde direction. Four days after perihelion, the Sun’s normal apparent motion resumes at these points.”

    Spin-orbit resonance*

    “For many years it was thought that Mercury was synchronously tidally locked with the Sun, rotating once for each orbit and keeping the same face directed towards the Sun at all times, in the same way that the same side of the Moon always faces the Earth. However, radar observations in 1965 proved that the planet has a 3:2 spin–orbit resonance, rotating three times for every two revolutions around the Sun; the eccentricity of Mercury’s orbit makes this resonance stable — at perihelion, when the solar tide is strongest, the Sun is nearly still in Mercury’s sky.

    “The original reason astronomers thought it was synchronously locked was that whenever Mercury was best placed for observation, it was always nearly at the same point in its 3:2 resonance, hence showing the same face. This is because, coincidentally, Mercury’s rotation period is almost exactly half of its synodic period with respect to Earth. Due to Mercury’s 3:2 spin-orbit resonance, a solar day (the length between two meridian transits of the Sun) lasts about 176 Earth days. A sidereal day (the period of rotation) lasts about 58.7 Earth days.

    “Simulations indicate that the orbital eccentricity of Mercury varies chaotically from nearly zero (circular) to more than 0.45 over millions of years due to perturbations from the other planets. This is thought to explain Mercury’s 3:2 spin-orbit resonance (rather than the more usual 1:1), since this state is more likely to arise during a period of high eccentricity.”

    *Source: Wikipedia — Mercury (planet).

  36. Radwaste

    Heh. Impact craters. I have a forum full of faithful Christians totally stumped at how to explain the craters on Earth given the fundmentalist Biblical timeline. It’s one of the many things The Faithful duck.

  37. twobyfour

    DrFlimmer, what do you think what is on this picture?

  38. twobyfour
  39. twobyfour, since you linked to an Electric Universe site I can assume you are impervious to logic or data, but since you brought it up, I found a paper that indicates the threshold for elliptical craters is much smaller, more like 12 degrees. The lower the tensile strength of the material in the surface, the lower the angle has to be before you get elliptical craters.

    These are not craters dug by the impactor, they are carved out by the explosion’s shock wave, which is generally circular.

    Given that we see asteroids all the time, and have even seen them hit large bodies, why bother making up stuff like lightning from other objects which has never been seen and cannot possibly occur?

  40. StevoRaine

    @ SLC – Did you ever see my answer for your question about giants and supergiant stars wa-aay back onthe R leopris thread?

    (“Keck twins view dying stars last gasps” I think the thread was called -animation zooming in to image of Mira variable similar to Hind’s Cromson Star.

    @ the BA : Did you see the Croswel article on Mercury’s orbital instability? Have you posted about it anywhere?

    Oh & plesae could we get the ability to edit our posts here?

  41. DrFlimmer

    @ twobyfour:

    The Tunguska event was radial, too, if I remember correctly. You don’t want to tell me that it was a giant lightning, do you?

    Yes, that asteroid didn’t hit, but that’s not the point. The Arizona crater (what’s its name?) is also quite round, and the object most likely didn’t fall straight down. Or was it also lightning?

  42. Anaconda

    @ twobyfour:

    The messenger flyby did report a phenomenon known as “sputtering” where charged particles flow down to the surface of Mercury through the weak magnetic fields and knock off neutral atoms and send some of them into space. Certainly not a lightning bolt, but an electromagnetic process, nevertheless, removing material from Mercury’s surface and launching a portion of it into space.

    Check out this NASA diagram and note where “sputtering” is mentioned.

    What is leftover after “sputtering” has knock these atoms into space? Of course, it all depends on how energetic the “sputtering” process is, but if it’s energetic, could there be a pockmark of some kind? And what would it look like?

    Also, note how electromagnetism plays a dynamic role in Mercury’s near-space environoment.

    Also, note that electromagnetic phenomenon is scale independent. What would be the result if the Sun’s solar wind was much stronger than at present?

    Would the “sputtering” phenomenon be increased in scale?

    NASA reports on “sputtering” — interesting.

  43. DeiRenDopa

    @Anaconda: “note that electromagnetic phenomenon [sic] is scale independent”. No, electromagnetic phenomena are not scale independent! :-( Wherever did you get such a silly idea?

    Or perhaps you just read it somewhere (I wonder where?), but didn’t understand what you read?

    Generally you need a microscope to see the direct effects of sputtering; at sufficiently high intensity, ion bombardment would simply result in a general degradation of features, a smoothing of sharp edges, a softening.

  44. Davidlpf

    @Ivan3man, you almost hit my home with that overlay, luckly the crater ended on the other side of Maine. Try further south and west next time.
    @Twobyfour, all I see like the rest are impacts.

  45. @ DeiRenDopa:

    With all due respect, it is well known that electromagnetic phenomenon is scale independent up to 14 orders of magnitude and, in fact, no limit to electromagnetism’s scalability has been identified.

    See the link below and please scroll down to the bottom of the page to note the peer-reviewed published papers supporting plasma’s scalability.

    Examining twobyfour’s linked picture, it would seem that your assertion, of “a general degradation of features”, is not backed up by the evidence.

    I’ve offered authority for my positions, NASA, and peer-reviewed papers. DeiRenDopa where is your authority?

  46. (click on my name for the link).


    Engineering, Electronics. a process that uses ions of an inert gas to dislodge atoms from the surface of a crystalline material, the atoms then being electrically deposited to form an extremely thin coating on a glass, metal, plastic, or other surface.


    verb (used without object)
    1. to make explosive popping or sizzling sounds.
    2. to emit particles, sparks, etc., forcibly or explosively, esp. accompanied by sputtering sounds.
    3. to eject particles of saliva, food, etc., from the mouth in a light spray, as when speaking angrily or excitedly.
    4. to utter or spit out words or sounds explosively or incoherently, as when angry or flustered. 😛

    verb (used with object)
    5. to emit (anything) forcibly and in small particles, as if by spitting: The fire sputtered cinders.
    6. to eject (saliva, food, etc.) in small particles explosively and involuntarily, as in excitement.
    7. to utter explosively and incoherently. 😛

    8. the act or sound of sputtering.
    9. explosive, incoherent utterance.
    10. matter ejected in sputtering. 😛

  47. @ Ivan3Man:

    NASA’s got you sputtering all over yourself:-)

  48. MadScientist

    @IVAN3MAN: Thanks for the correction (bah – time to take a marker pen and censor old books). However, given the timing of the change in lighting, that still precludes the lighting changing from left-to-right in two superimposed images.

  49. IVAN3MAN


    Ivan3man, you almost hit my home with that overlay, [luckily] the crater ended on the other side of Maine. Try further south and west next time.

    Other side of Maine? So, I presume, David, that you reside somewhere in Nova Scotia, then?

  50. IVAN3MAN

    @ MadScientist,

    You’re welcome. As for the image in question, I think that the right-hand quarter section was taken during the first flyby, and the left-hand three-quarter section was taken during the second flyby; then, the two images where digitally combined. However, I’ve not been able to locate the two seperate image sections on the MESSENGER web-site.

  51. IVAN3MAN

    ERRATUM: “where” should be were!

  52. Davidlpf

    @Ivan3man, new brunswick if you see the redline that seperates Maine and New Brunswick. Follow it down to a small bay that emptys into the Bay Fundy. The town I work in is on the bay and I live a little upstream from there.

  53. IVAN3MAN

    @ Anaconda,

    If we were to conduct a vote among readers of Bad Astronomy/Universe Today, I think that we would find that it is you who is the one doing the “sputtering” around here and especially at UT!

  54. @ Ivan3Man:

    Science isn’t up for a vote.

    And, by the way, since my first series of comments, here, on Bad Astronomy, how many different reports from NASA have recorded or confirmed electromagnetism in the solar system.

    Electromagnetism has a pretty good track record — you — not so much.

  55. IVAN3MAN

    @ Davidlpf,

    I’ve just been checking out Google Earth and, from your description, I presume that you work in the town of St. Andrews; is that correct, David?

  56. Davidlpf

    Okay you are good.
    Sorry not helping you with anaconda but I am doing a little research.

  57. Greg in Austin


    In what scientific journal can I find the peer-reviewed articles that describe how you performed your studies on electromagnetism? I would like to repeat those experiments myself.

    That is how science works.


  58. Awesome article!!Nice pics…

  59. IVAN3MAN

    @ Anaconda,

    As one of the four fundamental forces of the Universe, electromagnetism in space is not what is in dispute here or at Universe Today. What is in dispute is the assertion by “Electric Universe” proponents, such as Anthony (“Dead Parrot”) Peratt, that the entire Universe is driven by electromagnetic forces.

    I am not the one making such claims here nor at Universe Today; it is you, Anaconda, and your “Electric Universe” cohorts, that are making those claims. So, to quote the late Prof. Carl Sagan: “Extraordinary claims require extraordinary evidence”.

  60. Mercury: Electromagnetic near-space environoment
    Earth: Electromagnetic near-space environoment
    Jupiter: Electromagnetic near-space environoment
    Saturn: Electromagnetic near-space environoment

    I’m just parroting the NASA reports.

    Got a problem — take it up with NASA.

  61. Davidlpf

    Mercury-iron core
    Earthe -iron core
    Saturn/Jupiter-metallic hydrogen
    All can generate magnetic feilds when they spin, and behold they all spin.

  62. IVAN3MAN

    @ Davidlpf,

    Thank you for saving me the trouble to respond to Anaconda. It’s getting late here in London, UK — 05:00 UTC!

  63. @ Davidlpf:

    Your comment omits the pertinent observation & measurement that an electromagnetic connection exists between the Sun and the planets I listed above. This post reports the electromagnetic connection (Flux Transfer Events and magnetic ropes, Birkeland currents, aka electric currents) and interaction between the Sun and Mercury.

    Better check out the, above, link to the schematic NASA produced to reflect the observations & measurements recorded.

    Got that, David, electric currents connect the Sun and Mercury. That is the scientific fact, no matter how much you don’t like it.

    Your comment is the reaction of somebody hearing fingernails on a chalkboard.

    Resigned silence is better than half-truth comments.

  64. @ Ivan:

    As for the image in question, I think that the right-hand quarter section was taken during the first flyby, and the left-hand three-quarter section was taken during the second flyby;

    Another “Duh!” for me. Yes. Looking at the flyby animations on the mission website, that would appear to be the case. Although I’m not sure if maybe it’s the other way around, in terms of which side was photographed first.

  65. khms


    Nobody is in any doubt that there’s a lot of electromagnetism around in the universe. It is, after all, one of the four fundamental forces.

    So proclaiming that “hey, here’s another place where someone has found some sort of electromagnetic effect” isn’t particularly surprising, nor does it do anything to prove that some specific effect was due to electromagnetism and not something else.

    For that, you need arguments specific to the effect in question.

    So, just to be clear: what, exactly, was your claim that all your arguments are supposedly in support of?

  66. DrFlimmer

    @ Anaconda:

    Probably off topic, but solrey never answered my question. Probably you do: How is it possible that neutral hydrogen clouds fly around in galaxies with the same velocity as the stars?

  67. DeiRenDopa

    @Anaconda: you said “electromagnetic phenomenon [sic] is scale independent”, you didn’t say “some plasma behaviors are scale independent”; with all due respect the two are very different.

    In fact, your webpage makes it very clear that there are significant limitations to plasma scaling.

    Anaconda, you seem to be very ignorant, spouting physics words that you obviously do not understand, and stringing them together to produce conclusions that are nonsense. Are you one of those electric universe cultists?

  68. DeiRenDopa

    Oh, I forgot: what is 2×4’s photograph? He didn’t say (it looks like the skin of a cantaloupe to me).

  69. DeiRenDopa

    @Anaconda: I just read this “NASA have recorded or confirmed electromagnetism in the solar system”.

    Now I’m sure; you have no clue, do you, what “electromagnetism” is!

    Holy FSM, go out on a cloudless night, look up at the sky; at least one of the Moon, Venus, Mars, Jupiter, Saturn will be there. See them? Good. You will have just confirmed that electromagnetism is in the solar system! (I’d advise you to check out the Sun, but then its electromagnetism might damage your eyes!!)

    What did they teach you in Science classes at school man?

  70. DeiRenDopa


    Teacher! Teacher!! I know!!!

    Its cause the stars have hydrogen and electromagnetism is in the stars!!!!

    Besides, Chief Acolyte P said so, so there.

  71. You guys are silly.

  72. Did I mention I like that?

  73. Davidlpf

    At Anaconds school the taught that evil 17th century occult theory of gtavity so the teachers must be wrong. Anaconda ingores all that and gets his real education of the net where everything is true.

  74. DrFlimmer

    @ DeiRenDopa:

    Sit down, again. I’ll get back to you later, after I’ve listend to more serious stuff 😉 😀

    I was talking about neutral hydrogen… the hydrogen is not neutral in stars…. 😉 (just to make that clear to some other folks…)

    But, you are right about the other thing: Photons are the transmitters of the em-interaction. I wonder, why those guys never talk about this one 😉

  75. Anaconda:

    … it is well known that electromagnetic phenomenon is scale independent up to 14 orders of magnitude and, in fact, no limit to electromagnetism’s scalability has been identified.
    See the link below and please scroll down to the bottom of the page to note the peer-reviewed published papers supporting plasma’s scalability.

    That article was plagiarized verbatim from Plasma Scaling — Wikipedia (click on my name for the link), and stopping short of “Dimensionless parameters in tokamaks”.

  76. That article was plagiarized verbatim from Plasma Scaling — Wikipedia

    The citations of which seem to range from 1941 to 1966. Surely such an exciting field has seen more recent activity?

  77. With my emphases where appropriate, this is an extract from Plasma Scaling — Wikipedia:


    While these similarity transformations capture some basic properties of plasmas, not all plasma phenomena scale in this way. Consider, for example, the degree of ionization, which is dimensionless and thus would ideally remain unchanged when the system is scaled. The number of charged particles per unit volume is proportional to the current density, which scales as x-2, whereas the number of neutral particles per unit volume scales as x-1 in this transformation, so the degree of ionization does not remain unchanged but scales as x-1.


    The first thing to notice is that many cosmic phenomena cannot be reproduced in the laboratory because the necessary magnetic field strength is beyond the technological limits. Of the phenomena listed, only the ionosphere and the exosphere can be scaled to laboratory size. Another problem is the ionization fraction. When the size is varied over many orders of magnitude, the assumption of a partially ionized plasma may be violated in the simulation. A final observation is that the plasma densities needed in the laboratory are sizeable, up to 1016 cm-3 for the ionosphere, compared to the atmospheric density of about 1019 particles per cm3. In other words, the laboratory analogy of a low density space plasma is not a “vacuum chamber”, but laboratory plasma with a pressure, when the higher temperature is taken into consideration, which can approach atmospheric pressure.

  78. Good post, adding it to my blog now, thanks.

  79. Well first, lets start with getting to Mars, then moving on to Mercury


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