You can send an observation about rare cloud forms by filling out this form.

Examples of clouds within this observation program:
  • Polar stratospheric clouds -clouds, sometimes visibe at wintertime
  • Noctilicent clouds, sometimes visible during summer nights
  • Rocket exhaust clouds

Observation start

When did you see or photograph this phenomenon?

  • *
    info

    Please enter here the date and time when you first saw the phenomenon in the sky. The date can also be chosen from the calendar icon next to this. The date and time should be given according to the local time of the observation location.

    If you are not sure of the time you saw the phenomenon, we ask you to give us the time you think is the most likely, meaning your so called best guess. In this case, we would like you to tell more about the uncertainty surrounding the time in the free-form text -field meaning the observation strory.

    If your observation is about a celestial body taken with long exposure, which may have been even been exposed on several different nights, please give us the latest time of exposure.

  • *
    Observation starts
    —  
    Observation ends
  • If the phenomenon lasted only a short while (a couple of minutes or so), giving just the start time is ok.
  • Quick selects
    Phenomenon still visible • was visible 30 min ago • was visible 1 h ago
Observation location

Where were you when you observerd the phenomenon?

  • Please choose your observation site
    by clicking the right location on the map.

    info

    When you click the map with your mouse, the system will automatically pick the coordinates of the place you have chosen and on land usually also the name of the place in question. 

    If your first click of the map hit the wrong place, you can move the location marker by clicking the map again. Zooming in on the map with the slider in the left-hand corner of the map or the mouse scroll wheel helps with making the placing more accurate.

    If for some reason you are not willing to give us your observation location too precisely, you can place the observation location´s icon on the map for example in the center of the nearest small populated area. Normally an accuracy of 1-3 kilometers is enough to inform about the observation place. 

  • * info

    We hope our users will first give us the observation location within 1-3 kilometers of accuracy, if possible, by clicking the right spot on the map. In this case, the observation location will automatically appear below within the accuracy of the municipality, if the observation was made on Finnish grounds.

    Google maps won´t recognize all foreign observation locations nor observations made at sea. In these cases we would like for you to type the observation location here. 

    You can also, instead of clicking the map directly, type out the observation location´s name within the municipality´s accuracy in the ""City/municipality"" -box. In that case, the system will place your observation in a random place in the center of the municipality in question. Regarding multiple observations, this is also a good enough precision.

    If you don´t know, which municipality your observation was made in, like for example, you were in a moving vehicle, we would like you to describe the location in free form. For example ""Between Kouvola and Mikkeli"" or ""In an airplane above the Baltic sea"".

    If you marked your location on the map, this information will be filled in automatically

Contact info
  • + Add an observer info

    You can also mention other observers of your observation, if they are in the same observation location, have agreed to a shared observation and you announce their real names and email addresses.Only you as the main observer have the right to edit the observation and only you hold the copyright of the possible photos or drawn illustrations.

  • info

    Please give your actual name in the form of your first and last name. Observations can´t be accepted if only initials or an incomplete name are given (e.g. K. Virtanen). If you don´t want your name to be visible on the internet in relation to your observation, you can remove the checkmark from the spot asking this. The spot is displayed on the next line.


  • info

    Your aforementioned name will not be visible on the internet in relation to your observation and possible images, if you remove the checkmark here. If you remove the checkmark, on the observation´s name -field online will read ""Anynomous"". In that case your identity will remain only in Ursa´s and the phenomenon´s researchers´ knowledge. 

    Although we hope, that as many observer as possible allows their name to be displayed in relation to their observation and possible images. This way we can abide by the tradition of scientific observation which is seen as more important.


  • info

    The email address should be in a working basic form without unnecessary texts, spaces or brackets. For example: james.t.kirk@gfail.com

    If you want to later fill in, fix something about or completely delete your observation, it is possible using the editing link. The editing link will be sent to the email address you have given us. Without a working email address the link won´t arrive to you.

  • Why do we ask for contact information?

    info

    Your contact information will not be publicly visible nor will it be given away for commercial purposes.

    For research purposes: in case of especially valuable observations, it is important, that researchers or Ursa can contact the observer to ask more details or pictures or to thank the observer for the valuable input.

    You can later search for your observations using your own email address in system´s search bar. It is easier to search for observations by using your email address instead of you name, because some observers may share the same name with you.   

    Many observers have wished for an option to later modify their observations. This is possible only by using the editing link sent to the email address you gave us. Without a working email address the link won´t reach you. 

Description
  • *
    info

    This form can be used to report certain rare cloud types from which Ursa collects observations.

    The observation program includes pearl clouds visible in winter, clouds associated with rocket launches, night shining clouds occurring mainly in high summer time, and some special lower atmosphere clouds such as horseshoe clouds, lenticularis stacks, hole punch clouds, and roller cloud.

    With regard to night shining clouds (noctilucent clouds), enthusiasts also make so-called negative observations, stating that this phenomenon was _not_ visible even if there was every possibility of its occurrence (sky perfectly clear, visibility up to the horizon good and time suitable for night clouds).


*

Choose the alternative that best fits into your description of the phenomenon

Noctilucent clouds visible between clouds

Yöpilviä pilviraosta

Night shining clouds seen through cloud cover 

Night shining clouds are visible from cloud holes that are so small that their extent and brightness cannot be properly defined.

Very dim night shining clouds

Hyvin heikkoja yöpilviä

Very dim night shining clouds

The noctilucent clouds are so dim that they only appear in photographs or require experienced observer's eyes to be detected.

Dim night shining clouds

Himmeitä yöpilviä

Dim night shining clouds

The brightest forms of the noctilucent clouds, even though they still appear dim.

Clearly visible night shining clouds

Selvästi näkyviä yöpilviä

Clearly visible night shining clouds

The brightest forms of noctilucent clouds displayplay are clearly visible. Their brightness is comparable to the normal upper clouds illuminated by the Moon.

Bright night shining clouds

Kirkkaita yöpilviä

Bright noctilucent clouds

The brightest forms of the night shining cloud play are quite clearly visible. Their brightness is comparable to the cumulus clouds illuminated by the Moon.

Eye-catching night shining clouds

Huomiota herättäviä yöpilviä

Eye-catching night clouds

The brightest and dominant forms of the night cloud play are bright and eye-catching. They also attract unfamiliar public's attention.


  • info

    From the options, select the range of clouds in the sky that you observed. If ordinary lower clouds partially obscured visibility into the night clouds, this may be worth mentioning in the observation report.


  • *
    info

    We ask that you evaluate the phenomenon you have observed.

    Was the phenomenon weak or very faintly visible in the sky? Or was it clear or even very bright?

    If the most relevant content of the observation is a photograph, we hope that you will use the classification as follows:

    I: The subject is difficult to distinguish from the image.

    II: The subject is dimmed and / or small in the image.

    III: The subject is moderately visible in the image.

    IV: The subject is relatively extensively and / or brightly displayed in the image.



  • info

    Here you can type the name of the astronomical association which you are a member of. If you belong to more than one association, we ask you to give us the name of the association which is the most important to you havaintotoiminnassa.  

    The largest astronomical association in Finland, The astronomical association Ursa ry with its good 15 000 members is divided into area specific teams here. The teams are ""Ursa (Southern Finland)"", ""Ursa (Helsinki)"", ""Ursa (Eastern Finland)"", ""Ursa (Western Finland)"" and ""Ursa (Northern Finland)"". The Oulu and Lapland provinces belong to the Northern Finland team´s area. All municipalities in the metropolitan area, except Helsinki, are also part of the Southern Finland team´s area.      


  • We hope that you will tell about seeing the phenomenon in free form. If you are busy, even a one or two sentence long description of the phenomenon will help to understand, what you saw. (In case you want to input technical information, they have their own place)

    info

    Here you can tell in free form about the phenomenon and seeing it. You have a room of 1200 characters for that. For example how you spotted the phenomenon? How did it look like? (etc).

    If you are not already familiar with celestial bodies/atmospheric phenomena, please try to describe the phenomenon diversely.  

    In case you are a specialist in the field we hope you will write in a way that the observation story is at least for the most part comprehensible to new people interested about the subject. It is recommended to avoid terms, slang and abbreviations that only few can understand.  

    If you decide to write an observation story with at least a few sentences of length here and attach at least one image to your observation, the observation will be published on the observation system´s Images and stories page.

    Please use English when writing into this field. If you want to use some other language, select the alternative from the site banner.

    characters left.


  • You can attach 1-8 images or videos of the phenomenon (jpg, gif, png or mp4). The system will not receive files containing more than 50 megabytes. We hope, that you favor images or videos with no more than 15 Mb.

    info

    You can attach at most 8 images. We hope you will attach several images only if they showcase the different sides or stages of the phenomenon or otherwise fulfill eachother. If your images are practically fully identical, we ask you to only attach the best photo to your observation.

    The system automatically shows large images in a size where the longest side of the image (either horizontal or vertical) is 1000 pixels long.  

    The size limit of files is 50 megabytes. Taivaanvahti will not accept larger images. It is recommended to favor pictures that are at most the size of 15 Mb.

    The allowed image file formats are jpg, jpeg, gif ja png. The system will not accept for example tif images or pdf files.

  • Main image









  • info

    By crossing this off you´re asking the administration´s experts to inspect the observation´s phenomenon identifications particularly carefully and/or critically before the observation is published.

    In case something problematic is detected regarding the identifications, the observation won´t be published before the administration has fixed the identifications and/or you have been contacted.   

Additional information

You can describe your observation equipment or other technical details here.

info

If you want to, you can specify the observation equipmet or  phototechnical/processing information here. For that, you have 1200 characters at your disposal.

A telescope description can be stated for example like this: 127 mm reflecting telescope of 1300 mm focal length.

The photo information can be stated for example like this: Camera brand, 50 mm, f/2,8, ISO 100.


Noctilucent clouds

If you are unfamiliar with these phenomena, read the instructions on the information buttons. Experts can correct identifications if necessary.

info
info

The night cloud vail is a vague thin night shining cloud with no clear structure.

Noctilucent cloud veil with one strong belt formation. Image by Veikko Mäkelä.


info

Bands of noctilucent clouds are long, stripe like cloudformation.

A single, very bright NLC band. Photo by Mikko Peussa.

 

On the upper left corner, rising bands are clear on the image. Whereas waves of NLC cover the bottom right side of the image. Photo by Juha Tonttila.


info

Waves of noctilucent clouds are short, close groups of clouds.

Wavy NLC by Jari Luomanen.

 

NLC waves by Hannu Määttänen.


info

Swirls are curved night shining cloud forms. For example, a single night cloud belt or group of waves may be curved on a clear bend.

The arrow indicates a slight vortex in the night cloud belt. Photo by Joni Tahkoniemi.

Strong swirls in image taken by Veikko Mäkelä.


info

Relatively rarely, there are special shapes in the night shining cloud displays that do not belong to the shapes listed above. Such may be, for example, thick lumpy formations that appear as some kind of patches. They may also be associated with an unusual color tone.


Nacreous clouds
info
info

Nacreous clouds (mother-of-pearl clouds) are clouds that occur in winter and are best seen at dusk in the morning and evening when the Sun is below the horizon.

Although the name of pearl clouds refers to spectral colors, colorless, pale nacreous clouds are mainly observed in Finland. A striking feature related to pearl clouds in Finland is also the strong brown, which makes the landscape bathe in intense red or purple light.

The Sky Watch has categories for colorless elections (type I) and colored (type II) pearl clouds, as well as the brown subtype.

This selection reports type I colorless pearl clouds. While ordinary clouds are located in the lowest layer of the atmosphere in the troposphere, pearls form in the stratosphere above this at a height of 15 to 25 km above the ground. They occur when the stratosphere is exceptionally cold, about -75 ...- 85 C. The particles that cause pearls are either pure water ice (type II) or chemically different crystals, all of which contain nitric acid (type I) as an ingredient.

Changes in stratospheric thermal conditions are quite sluggish, which is why pearl clouds are seen continuously for at least a few days unless the lower clouds obscure the view. Nacreous clouds can be extensive in their occurrence and can occur simultaneously throughout Finland. However, the focus of the performances is in Lapland. The appearance of nacreous clouds in the sky can be predicted by stratospheric temperature predictions.

Nacreous clouds observations made in Finland from 1996 to 2014 show that they had been seen from December to March. Most occurred in December-January, in March nacreous clouds were reported in only one year. The particles responsible for the pearl clouds can also give rise to the Bishop ring. The Bishop’s ring may be a clear sign of nacreous clouds when the Sun is on the horizon. The pearl clouds themselves usually stand out when the Sun is on the horizon, but in this case they are usually very ghostly cloud fibers and easily go unnoticed

Type I nacreous clouds. Image by Panu Lahtinen.

Noctilucent clouds like nacreous clouds of type I. Image by Mikko Peussa.

Half an hour before sunset, wavy nacreous clouds. These nacreous clouds stood out exceptionally well from the daytime sky. Image by Marko Riikonen.


info

Pearl clouds (Nacreous clouds) are clouds that occur in winter and are best seen at dusk in the morning and evening when the Sun is below the horizon.

Although the name of pearl clouds refers to spectral colors, colored (type II) pearls are rare in Finland. We mainly see colorless, pale (type I) pearls. A striking feature related to pearl clouds in Finland is also the strong brown, which makes the landscape bathe in intense red or purple light.

The Sky Watch has categories for type I and II nacreous clouds, as well as the brown subtype. This selection reports pearl clouds representing type II spectral colors.

While ordinary clouds are located in the lowest layer of the atmosphere in the troposphere, nacreous clouds form in the stratosphere above this at a height of 15 to 25 km above the ground. They occur when the stratosphere is exceptionally cold, about -75 ...- 85 C.

The particles that cause pearl clouds are either pure water ice (type II) or chemically different crystals, all of which contain nitric acid (type I) as an ingredient.

Changes in stratospheric thermal conditions are quite sluggish, which is why pearl clouds are seen continuously for at least a few days unless the lower clouds obscure the view. Nacreous clouds can be extensive in their occurrence and can occur simultaneously throughout Finland. However, the focus of the performances is in Lapland.

The appearance of nacreous clouds in the sky can be predicted by stratospheric temperature predictions. Pearl cloud observations made in Finland from 1996 to 2014 show that they had been seen from December to March. Most occurred in December-January, in March pearl clouds were reported in only one year.

The particles responsible for the pearl clouds can also give rise to the Bishop ring. The Bishop’s ring may be a clear sign of nacreous clouds when the Sun is on the horizon. The pearl clouds themselves usually stand out when the Sun is on the horizon, but in this case they are usually very ghostly cloud fibers and easily go unnoticed.

In the winter of 2012-2013, Finland experienced an exceptionally long 13-day pearl cloud streak. On the second to last day of the episode, rare spectral colors also appeared in the clouds. Photo by Matti Helin.


info

Pearlescent brown is a brownish sunset associated with pearl clouds that appears at dusk in the morning and evening when the Sun is below the horizon.

It is usually remarkably powerful and makes the landscape bathe in red or purple light. Most often, some degree of pearlescent is observed in the context of pearl clouds. Pearl brown can also be the dominant element in which the actual pearl clouds stand out poorly if at all.

The pearl clouds themselves are reported in the Sky Watch in the categories of colorless light (type I) and spectral color (type II) clouds.

Parel clouds are often also associated with the Bishop ring. The Bishop’s ring may be a clear sign of pearls when the Sun is on the horizon. In addition, pearlescent cloud fibers are visible, which, however, are often very inconspicuous when the Sun is on the horizon.

The Pearl Bishop gradually turns into a pearl brown in the evening as the sun continues to sink below the horizon. In the morning the opposite. However, the Bishop ring is not always visible, even if pearl clouds are observed in the morning or evening. In this case, the pearlescent brown would also appear to be weak or non-existent.

Sunset colors with pearl clouds Eetu Saarti.

Close up of mother of pearl brown. It also shows type I pale pearl clouds. Photo by Mika Aho.

Pearlescent sunset by Veikko Mäkelä. 


Rocket launch
info
info

The rocket contrails are colorful clouds that appear when the sun is below the horizon. The contrails can float so high in the atmosphere that the sun shines on them even if it is already completely dark on the ground. They stay visible noticeable quite long after the launch.

The colors are created by the scattering of sunlight in the small ice crystals. In Finland, rocket phenomena from two different locations have mainly been observed. One of them is the missile launches from the submarines from the White Sea and the Arctic Ocean. They use solid fuel that creates colorful clouds.

Another source of rocket phenomena is the Plesetsk Cosmodrome Area in Russia. There are a few launches from there every year. These fires usually use liquid fuels, making the clouds less spectacular.

The visibility of the rocket launch is affected by the time at which the launch is made and where the winds blow. The best of all is around 3-5 o'clock Finnish time, when the cloud has time to spread out a bit and shine in the morning sun coming from the east when it is still dark or dark in Finland.

During the first decade of the 2000s, rocket phenomena have been observed about twice per year in Finland. Since then, however, it has been quieter.

Rocket contrails from Oulunsalo, Photo by Jarmo Moilanen.



info

Barium clouds have very rarely been seen in the sky during rocket launches. Typically a space organization has done an experiment in which a barium cloud is released into the upper atmosphere.

  


Other special clouds
info
info

The Undulatus asperitas cloud was approved for the International Cloud Classification in 2015.

Previously, the cloud was called Undulatus asperatus. These are udders resembling mammatus clouds, which, however, are wavy in their basic shape.

Undulatus asperitaxis has typically been observed in the morning and noon hours after convective thunder cell formation.

Either clear or spectacular undulatus asperitaxes are collected in the sky. Strong, large-scale and clearly perceptible waves should be visible on the underside of the cloud. Sample images of undulatus asperitas.

Undulatus asperitas -clouds. Photo by Miikka Mäkinen.


info

The Kelvin-Helmholtz clouds are among the most exotic apparitions in the cloud world.

They resemble regular waves in shape, typically several in succession. String wave strings are created at the top of the cloud mass when there are layers of air moving at different speeds in the air.

If there is moisture in one layer of air, it may rise into waves in another layer of air moving at different speeds. There is Kelvin-Helmholtz instability between the air layers at that time, from which the cloud waves are named.

Waves in lakes and seas are the result of this same instability between layers moving at different speeds. Kelvin-Helmholtz waves can also be seen in the gas circles of Jupiter and Saturn, for example.

Only clearly wavy cases can be called Kelvin-Helmholtz clouds. It is good to be careful not to confuse them with conventional undulatus clouds. The cloud types can be difficult to identify, especially when viewed from the side.

In a real Kelvin-Helmholtz cloud, the wave structure is clear. Only well-developed and undisputed Kelvin-Helmholtz clouds are collected to the Sky Watch database.

Wavy Kelvin-Helmholz clouds. Image Grahamuk / Wikipedia.

Tom Eklund observed these Kelvin-Helmholtz clouds in Finland.


info

Stacked lenticularis clouds, is a phenomenon in which there are several lentil-like clouds piled on top of each other. In the sky watch, the practical boundary between the conventional altocumulus lenticularis and the rarer lenticularis stack is considered to be at least three overlapping lenticular, i.e. layer-like, clouds.

Lenticularis clouds are streamlined, flat cloud shapes. Typically, they occur when a mountain or mountain causes a vertical disturbance to the air flow. At the top of the resulting air wave, moisture may condense into cloud droplets, allowing a smooth lenticular layer to be observed. Sometimes such clouds also form without strong terrain in connection with various weather phenomena.

Lenticularis clouds themselves are not uncommon and they can be seen quite often. Overlapping lentil cloud layers are clearly a less frequently seen phenomenon. Such a layerish pile cloud is formed when the wetter and drier layers of air alternate in the air. At that time, moisture condenses in some layers and not in others, so that even a very large number of lenticular layers can be detected.

Only such clearly formed, layered lenticular clouds are collected in the sky due to their rarity.

In Iceland, a layered lenticular cloud formed in a wave caused by mountains. Image from Wikipedia.


info

Pileus stack

The pileus cloud typically occurs at the top of a thundercloud, forming a hat-like leaf above the main cloud. If at least three reeds are visible, the object can be considered a pileus stack.

In situations where the top of the main cloud passes through the reeds, it is more like a velum cloud (veil cloud).

pileus-pino

Image by Jari Ylioja


info

A horseshoe vortex cloud occurs when an upward flow in the atmosphere collides with a horizontally moving air mass. This may cause a horizontally rotating vortex. If moisture condenses in the vortex into cloud droplets, a very rare upside-down U-shaped cloud shape can be observed. Often such a vortex is only visible for a very short time, perhaps a few tens of seconds or minutes.

Typically, horseshoe clouds are said to be visible in the vicinity of supercellular storms, as they are associated with very strong upflows and wind torsions that are conducive to the formation of a vortex. Yet this cloud shape is observed just in conjunction with conventional Cumulus clouds and sometimes even very far from them against a completely blue sky. To detect this cloud, you should therefore be careful whenever cumulus cloud is generated as a result of upflows.


info

Fallstreak hole (Hole punch cloud) is a rare phenomenon observed in cloud cover.

Altocumulus clouds consist mainly of subcooled cloud droplets, which can be well below freezing, but which have not yet frozen in the absence of suitable freezing cores.

When freezing nuclei, such as small ice crystals, come into contact with the cloud, the droplets of clouds may begin to freeze outward from this point so that an annular opening appears to form in the cloud. Such an opening is called a hole cloud.

One source of freezing cores may be airplanes that create a cloud of holes as they pass through the altocumulus layer. Hole clouds can also be oblong in shape when the aircraft has flown a little longer at cloud height. In this case, ice crystals floating down from the opening remains in its path. In the middle of these openings or canals, a thin line of ice crystals, or Virga, visible below the cloud layer, can typically be seen. If the sun happens to be at a suitable distance from this rain line, a halo phenomenon, such as a side sun, can be detected in the wake.

A hole cloud formed in the Altocumulus layer with a rain line of ice crystals, or Virga, in the middle. Image by Jari Luomanen.


By sending in this observation I confirm, that I've read and understood the the observation system's privacy policy.
Fields marked with star (*) must be given before sending in the information.