Here you can select the time from which the observations will be displayed. The last month will be used by default.
In this case, the search results in the middle of the page will show the findings reported to the Skywarden during the past month.
By clicking on the word 'ends' with the mouse, you will also see the end time of the search period. This is useful in situations where you want to look at observations from a period in the past, such as reports from a particular week in Skywarden.
Especially when looking at observations for a particular time period, you may want to do the search based on when the observed phenomenon actually happened instead of the time when it was sent to the observation database. In that case, you may want to select 'Observed' instead of the default 'Sent'. Please note that the browser uses a cookie to remember your choice of the start time of the search. If you have enabled cookies and do not clear them from your browser's cache, the same browser will display observations from the same time window you last selected the next time you use it.
Please note that the browser uses a cookie to remember your choice of the start time of the search. If you have enabled cookies and do not clear them from your browser's cache, the same browser will display observations from the same time window you last selected the next time you use it.
The "Sent" -option retrieves observations submitted to the Skywarden during the selected time period, regardless of when those phenomena were seen in the sky.
The selection “observed” retrieves the phenomena that appeared in the sky during the selected period, regardless of when they were reported to the Skywarden.
You can choose to show only phenomena of the desired level of visibility in the search results. For example, "at least III" removes the phenomena classified as the weakest (I-II). Similarly, "at least V" removes from the results all but the relatively rare phenomena or those classified as very impressive (V).
Here you can do a free-text search to the observations
The given text will bee searched from observation titles,descriptions, technical details and identified phenomena
You can search for any persons observations by writing the observer's whole name or part of the name here. For example 'John Smith' or 'John S'
You can also performa a search based on asspciation/team name or part of the name, like "Lahden Ursa".The search will bring up observations, that exactly match the given string.
To find observations made in some specific location, type the municipality name to the search field. For example, "Mikkeli"
You can also list multiple locations by separating them with a comma.For example "Mikkeli, Hirvensalmi, Juva, Kangasniemi". In this case, the search will return findings that match the locations listed.
In this field, you can search for more detailed phenomenon identifiers included in the observation details.
Such are, for example, deep space object types such as "spiral galaxy" or "reflection nebula" or halo forms such as "sundog" or "sun pillar".
You can also list multiple types of phenomena by separating them with a comma. A search will bring up findings that match one or more of the terms you listed.
By narrowing down the search date limits and typing, for example, "northern lights", you can see all the northern lights seen within a certain time period.
Copyright © 2020 Sirpa Pursiainen. All rights reserved.
Visibility V / V
Great night in Keminmaa. Luminous northern lights filled the entire sky. Sar-arc also showed up.
Upea yö Keminmaalla. Valovoimaiset revontulet täyttivät koko taivaan. Myös Sar-kaari näyttäytyi.
ARC The arcs are wider than the bands and do not fold as strongly. The arcs are normally neither very bright nor active.
The arc is probably the most common form of aurora. When aurora show is a calm arc in the low northern sky it often doesn’t evolve to anything more during night. In more active shows the arc is often the first form to appear and the last to disappear.
The lower edge of the arc is usually sharp but the upper edge can gradually blend into the background sky. As activity increases rays and folds normally develop, and the arcs turn gradually into bands.
An aurora arc runs across the picture. Vertical shapes are rays. Photo by Atacan Ergin.
Aurora Arc. Photo by Mauri Korpi.
Aurora Arc. Photo by Anna-Liisa Sarajärvi.
Aurora Arc. Photo by Matti Asumalahti.
CoronaA corona is a hand fan shaped structure, it usually forms south of the observer's zenith, most commonly consisting of rays or bands. The corona is usually the most beautiful part of the aurora show. It is bright and active, but on the other hand also short-lived.
Aurora corona. Photo by Anna-Liisa Sarajärvi.
Aurora corona. Photo by Merja Ruotsalainen.
Corona formed from bands. Photo by Markku Ruonala.
Aurora corona. Photo by Tapio Koski.
Bands are usually narrower, more twisty at the bottom, brighter, and more active than arches. Bands usually develop from arches.
Bands can form J and U shapes, sometimes even full spirals. The corona can also arise from bands. Bands are a fairly common form of aurora.
Aurora band. Photo by Merja Ruotsalainen.
Aurora band. Photo by Matias Takala.
Aurora band. Photo by Lea Rahtu-Korpela.
Aurora bands. Photo by Lauri Koivuluoma.
The raysare parallel to the lines of force of the magnetic field, i.e. quite vertical, usually less than one degree thick light streaks. The rays can occur alone or in connection with other shapes, mainly with arcs and bands. Short rays are usually brightest at the bottom but dim quickly. The longest rays, even extending almost from the horizon to the zenith, are usually uniformly bright and quite calm, and unlike the shorter rays, most often occur in groups of a few rays or alone. Rays, like bands, are a very typical form of aurora.
Artificial light pillars, which are a halo phenomenon visible in ice mist, can sometimes be very similar to the rays of aurora. Confusion is possible especially when the lamps that cause the artificial light pillars are far away and not visible behind buildings or the forest. The nature of the phenomenon is clear at least from the photographs.
Rays. Picture of Tom Eklund.
Rays. Photo by Mika Puurula.
Two beams rise from the aurora veil. Photo by Anssi Mäntylä.
Two radial bands. Show Jani Lauanne.
Radial band and veil. Photo by Jussi Alanenpää.
Two rays. Photo by Aki Taavitsainen.
It may be possible to confuse such rays with artificial light columns. Compare the image below. Picture of Tom Eklund.
There is no aurora in this image, but all the light poles - including the wide and diffuse bar seen at the top left - are artificial light pillars born of ice mist. Photo by Sami Jumppanen.
Aurora and artificial light pillars. All the radial shapes in the picture above are probably artificial light pillars that coincide appropriately with the aurora band. In the image below, the aurora band has shifted and does not overlap with the pillars produced by the orange bulbs. There is no orange in auroras. Photo by Katariina Roiha
Red Arc with Green Diffuse Aurora (RAGDA), is a two-component form of northern lights that occurs south of the oval.
Both parts of the aurora are formed when positive particles from the magnetosphere hit the Earth's upper atmosphere. The phenomenon occurs before magnetic midnight during large aurora substorms and is best distinguished when it deteches southward from the bright rays of the substorm aurora.
The phenomenon consists of a faint red arc, which looks a lot like a Stable Auroral Red (SAR)-arc. The common factor for these two red arcs is the reaction of the ring current with the substorm.
A Red Arc with Green Diffuse AuroraPhoto: Antero Ohranen
Below the red arc are green diffuse patches or sausage-like shapes. RAGDA's green aurora is essentially featureless and without any rays. It may appear slightly more bluish in camera images compared to the green aurora of the oval.
RAGDA's green has slightly more bluish shade than the rest of the oval.Photo: Lasse Nurminen
Sometimes the red arc and the green patches are clearly separated from the aurora oval and sometimes almost in contact with the southward edge of the oval.
During an active substorm, the green northern lights can sometimes be seen with red tops. These usually have rays that RAGDA's green aurora lacks.
An emissionless gap without any aurora light can be observed between the red arc and green diffuse aurora. The two features don't seem to be connected. Of the two aligned structures, the red one is located ~ 100 kilometers higher than the green aurora.
There seems to be an empty area without any aurora light between the red and green aurora.Photo: Markku Ruonala
The event is dynamic. It sometimes starts with green blobs, then a red arc appears. These two can also appear in the sky at the same time. The shapes move often from east to west. Then the Red Arc with Green Diffuse Aurora fades away and only the red arc remains visible in the sky. The red arc is recognized as the SAR arc.
Observing this phenomenon is easier when the night sky is clear and dark before magnetic midnight. When looking for the red arc with green diffuse aurora, the best results can be achieved by pointing the camera towards south or southwest of the brightest part of the oval.
A wide-angle lens is recommended for photographing the shape of the red arc going over the sky, but a regular lens can also be used. The red arc is quite dim, so the exposure times needed are typically longer than the ones for northern lights.
Two RAGDA-arcsPhoto: Pirjo Koski
If the red arc cannot be distinguished in the images, the phenomenon identification 'Diffuse green auroras' should be used for isolated hazy green blobs/arc.
Dunes in RAGDA's green auroraPhoto: Matias Takala
Green, seen with the naked eye, is one the most common colors of the aurora. The green color is derived from atomic oxygen.
Green auroras. Lea Rahtu-Korpela.
Green auroras. Photo by Juha Ojanperä.
Auroras which have red top part that can be seen with naked eye are most often observed in the bands and long rays. In this case the lower parts are usually green. If the upper parts are in sunlight, red may be stronger than green. This shade of red is due to the discharge of the excitation state of the atomic oxygen.
Aurora that shift to reddish towards the top. Photo by Karri Pasanen.
Red top in a aurora band. Photo by Simo Aikioniemi.
Red at the top of the aurora. Picture of Tom Eklund.
Usually in Lapland or even in the south you can see purple auroras in stronger aurora shows. The most common color in auroras along with green and red.
Upeat kuvat ja mielettömän hienot revontulet! Millä objektiivilla olet nuo kauniit kuvat ottanut?
Kuvauskalustona Canon 6D ja Tamron SP 15-30, F2,8.
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