Noctilucent clouds

First view

First view

The day rumbled by in a torrent of rain, thunder and lightning yesterday. It finally broke with a glorious yellow sunset and rainbow. I put my digi-cam on charge to see if I could be fast enough to get it. Sadly not, though my film camera was a little more accommodating.

Looking Northwards

Looking Northwards

Later on, deciding that a rainy day was not the best sign of a nice clear night, I decided on an early night, but due to an unexpected Citizen sky survey, which appeared rather in depth, I stayed up a little later than expected. I never saw any of the meteor showers the BBC reported, but when the clouds did clear, I saw quite a different thing. A glow to the north.

Waves and ripples

Waves and ripples

It was immediately apparent that these weren’t auroral signals (though one or two did seem to follow the course of an auroral arc) and they didn’t quite seem like clouds lit up by the waning crescent Moon. I took a quick snap to see what the camera saw, then headed out to look a bit closer and to get a more northward view. The time was just before 3am, a good long while before sunrise.

Moon and Jupiter

Moon and Jupiter

Looking to the north, it was plain that the clouds were in the right position, glowing correctly and looking just like classic NLCs (a report from further south confirmed later that there was a noctilucent cloud show). Noctilucent clouds mean Night Shining clouds, they are the highest clouds around and are lit first by the unrisen Sun. When the Sun starts rising, the NLCs will have already vanished as they are no longer within the Sun’s grasp. They are also known as Polar Mesospheric clouds, which relates to where they are found – normally surrounding the polar region, normally at the height of the mesosphere.

Cloud, Moon, Streetlamp

Cloud, Moon, Streetlamp

NLCs weren’t the only things on show that morning as the skies had cleared. As well as the Moon mentioned earlier, Jupiter was shining brightly to its south. Neptune was next to it (as I had seen through the Celestron a few nights earlier, getting it, Neptune and a field star in one view in the 25mm eyepiece. Jupiter was bright enough to almost blot out the tiny blue dot of Neptune and even its Moons outshone the other planet and star), but as always invisible to the naked eye. Similarly, Uranus was underneath the Moon, but the brightness of that and the twilight did make the seventh planet even more difficult to see. By the end of the photoshoot, Venus had risen in the East and a glow permeated the horizon, captured in several of the shots. The NLCs were fading by 3:30am when I finished and were gone before sunrise. All photos in the set are available here.




11 responses to “Noctilucent clouds

  1. Pingback: Fantastic NLC display seen from Kendal… « Cumbrian Sky

  2. charles garner

    If you lived on a planet with rings like Saturn, then
    you would be looking at a sky full of noctilucent
    clouds. They block out the sun. These clouds
    are a prelude to an upcomming ice age. We are
    entering into the galactic plane where there is
    more cosmic dust that is causing this.

    • A nice thought, but they aren’t quite Mesospheric at Saturn (they are the lowest cloud level as opposed to very high, very thin upper cloud level here) and so aren’t NLCs. Additionally, NLCs are very seasonal and not linked to interplanetary dust levels (otherwise they’d follow the times of year when we pass through dustier bits of our orbit), though cosmic rays seem to have an effect on them and things like the exhaust from the space shuttle have a definite effect.

      It is more likely that as they appear in the mesosphere, which is coldest in Summer, the reflection of infrared radiation that causes warming on the surface of the planet and cooling at the top of the CO2 population in the atmosphere (most prominently at the mesopause) provides the conditions for the ice clouds to form. In effect it is global warming not cooling that provides these things with a home. In addition, the clouds are far too transparent to reflect significant amounts of sunlight and cause an ice age, but I suppose we can only hope they can be a mechanism for some cooling…

  3. I’m not talking interplanetary my friend. I’m talking intergalactic. We are entering into a photonic belt eminating from the central star Alcyon. Photons pack waves and particles.
    Have you noticed the record low temperatures
    reported this year in the U.S.A. Those particles
    are accumulating up there. The whole solar system is being affected; not just earth. There are magnetic affects as well evidenced by low sunspot activity which may be why global warming is a political euphemism for too many
    people polluting the earth. D’ont worry that carbon dioxide is not enough to stop the next
    ice age.

    • Central star Alcyon – how would that be intergalactic? Please see my earlier post on that crackpot theory. Photons pack waves and particles? I suggest you learn a bit of basic physics before posting here – photons do have wave-particle duality, but that doesn’t mean they are groups of waves and particles, it means they show the properties of both waves and particles in given situations. The low sunspot activity is part of a well known series of cycles that happen in the sun, not any strange magnetic effects. As for record low temperatures, there’s quite a difference between climate physics and weather. If you have a series of heaters warming gas in a room, you can calculate the climate by working out how much heat is going into and out of the room. The weather would be working out the thermal currents in each bit of it. Some bits would be warm, some cold, doesn’t affect the climate, but can be affected by it. Global temperature shifts are noticed in global data, not weather reports.

  4. I was just wondering if you think man might be a
    big contributing factor for global warming on earth then why do we have solar system warming. The ice caps on mars have receded.
    Sun spot cycles are not as well known as you say they are. How could they when we have only been recording the data for a few centuries. NASA keeps changing its predictions about solar max of the next sunspot cycle. It is the sun,
    and not man that determins part of our destiny. Man is not that capable of changing the planet. We are too insignificant on this planet which is whizzing through the universe with future unknown encounters as we experience periodic mass extinctions and ice ages. Yes there will be more of them.

    • We’ve been recording sunspots for a few millennia, not centuries – centuries merely refers to the period of continuous study in one single program. The main cycles last around eleven years, larger cycles go on for one and a half centuries. They are well known. Just because NASA hasn’t pinned down the exact moment of when the current solar cycle will hit its maximum doesn’t alter how well we know about the previous cycles, nor does it alter new information garnered from asteroseismology, showing subsurface plasma flows that match the cycles.

      We don’t have solar system warming, there were some anomalous readings. The ice caps on Mars recede and grow every summer and winter. They aren’t showing a trend whereby they recede further each year than the previous as is the case on Earth. Nor is the exospheric temperature of any other planets on a warming phase, unlike that of the Earth.

      You say man can’t alter the planet – remember the ozone layer and were the destruction came from? Cause and effect. It was pinned down, international agreements were thrown at it and the damage was mitigated. Carbon dioxide levels, exacerbated by man’s activities are well correlated to the measured increases in global temperature. The predictions of temperature rises made ten years ago based on the amount of CO2 and other greenhouse gases we were putting out were correct to within a few percent. The mechanism by which the warming happens is well known – diffusion of infrared radiation by CO2 and other greenhouse gases, which leads to cooling in the upper atmosphere, but when deflecting back light transferred into infrared radiation on the ground, leads to warming.

      Whether or not we head into new ice ages, and you’re right in that we most probably will at some points in the future, it won’t be due to the incorrect idea that the Sun, Sirius and other stars are in orbit of Alycone as dictated by the ramblings of John Keeley, partly through a medium.

  5. OK. I was just playing Devil’s Advocate about
    man not affected the planet. The billions of
    them that are contributing to the mass
    extinction of species that has already started.
    So what about limiting population growth?
    Of course there must be something better
    than man in the Universe or he would be able
    to do this without wars,famine,etc. It is a gene
    By the way, what would you say about the
    transfer of all that water from those lakes that
    are drying up to those ice crystals in those NLC’s. Hence, the Age of Aquarius-the water
    bearer. Get ready to fetch a lot of pails of water. Did the ancients know something we
    are only now relearning. And that photon
    belt must be doing something. We are going
    to be going through it for the next 2000 years.

    • I don’t personally believe in population control. As with the ozone problem, it was eventually mitigated by international action and adaptation. The species has adapted before and although wars and famine will continue, I like to believe those other things we can learn to control just enough will be controlled when the consequences of not acting become plain enough. The space race was born of competition between adversaries, this new problem need not turn out to be different, though there’s always the chance the competition will be more against each other for resources. That is a problem to be prepared for.

      The sea levels are rising rather quickly, even if water elsewhere is getting more scarce (by, globally, a far lesser amount). We face more a transportation problem than an overall water loss – as we do now in certain places. The NLCs, which only appear in their seasons in June-August, are very, very thin things – less than cigar smoke. They just happen to be rather reflective, so they don’t represent a great amount of water (although they do represent a relative increase in humidity at that altitude).

      Finally, there is no ‘photon belt’. The strength of photons coming from Alcyone is insignificant compared to that from the Sun, reflected from the Moon, reflected off the planets or even from the star Vega or many other stars. Why should Alcyone have a particular feature no other star exhibits? Involving special photons seen nowhere else, with never before noticed properties that not only defy the known properties, but haven’t actually been noticed in studies of that star – a young (relative to our own Sun) star (or rather set of stars) belonging to a well known cluster of which the Sun is not a part?

  6. There is one last view point I wanted to mention. Some say that the gravitational fields of the earth have been weakening.
    The South Atlantic Anomoly is getting
    stronger. One physicist predicts a magnetic
    pole reversal soon by stating that the interior
    of the earth is heating up. Since there is this
    inverse relationship between heat and magnetism as you heat up the interior of
    the earth the magnetic field or magnetosphere
    weakens which does seem to be the case now.
    Some scientists claim that vortices have opened up under the poles and that there is
    more volcanic activity which may be
    contributing to NLC”s. So, perhaps this is
    another reason for the polar ice caps thinning
    out. We are sitting on a hot plate so to speak.

    • I trust you meant “magnetic” not “gravitational fields” in the first bit… going on the rest of the comment, you did.

      We know that the magnetic field reverses periodically, that is recorded in the floors of the seabed. The field is starting to slowly weaken and the north pole is measurably on the move. This is similar to behavior shown by the Sun and is believed to be related to the dynamo action of the outer core of the planet moving around the inner core. As with the Sun’s field, it gets itself in a mess and sorts itself out by reversing. The South Atlantic Anomaly is affected by both the motion of the magnetic field (the field doesn’t lie quite in the core, it is offset and the SAA is where the field is furthest depressed into the Earth) and the strength of the field.

      The periods of magnetic reversal haven’t been shown to coincide with periods of internal heat generation or external heat generation. They don’t match iridium layers from periods of heavy volcanic activity for example, nor do they match the indicators of climatic activity. Historically, we’re not looking at a volcanic hot spot in time (either recent or longer time). But we are looking at a period of heightened awareness when volcanoes do go off – both in terms of actual eruptions getting photographed and the results of eruptions like the lovely volcanic sunsets created by the sulphur dioxide clouds spewed out (and yes, most probably NLCs).

      Although it is true that at the Curie Point, a magnetic will lose its magnetism, the Earth’s core is believed to be a lot hotter than this point already. It has no innate magnetism, which comes from electrical currents associated with the convection of materials within the core. This is not affected by temperature in the same way – hotter would mean more convection and so a stronger field. Geophysicists use this to measure temperature variations within the core by taking readings of the magnetic field.

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