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 Pentti Arpalahti, Emma Bruus, Kari A. Kuure. All rights reserved.
Visibility III / V
The momentary activation of the northern lights took hold of Ursa's weather cameras in Tampere.
Tampereen Ursan kelikameroihin tarttui hetkellinen revontulten aktivoituminen.
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
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.
Comments are checked and moderated before publication If you want to contact the observer directly about possibilities to use these images, use the Media -form.
* Real name
Along the years, several foundations have supported the development of this site.
Desktop version of the site
Show the mobile version
Site development by the Skywarden team and E. Bruus.
© 2011- 2022 Ursa Astronomical Association. All rights reserved.