v1.1 2014/12/03 J. Zamorano
A1. Meteors and fireballs detection
High sensitivity video devices have been commonly used for the study of meteor streams. The meteoroids (Solar System particles) are detected by the video cameras thanks to their light traces through the atmosphere (meteors). The orbit of the meteor could be reconstructed when the same meteor is registered by several cameras distributed at different sites (multiple-station orbit). The brightest meteors (fireballs) could yield a meteorite to be searched in the area predicted from the orbit. Meteorites are important for the study of the Solar System. The number of events registered depends on the number and distribution of the cameras.
European Networks:
 REseau Français d'ObseRvation de MEtéores www.reforme-meteor.net/

Spanish Meteor Network (SPMN)

Croatian Meteor Network www.spmn.uji.es/ http://cmn.rgn.hr/

UK Meteor Observation Network

IMO Video Meteor Network www.ukmeteornetwork.co.uk/) www.imonet.org/

Central European Meteor Network http://cement.fireball.sk/

European Fireball Network

Polish Fireball Network

Slovak Video Meteor Network

Italian Meteor Network www.asu.cas.cz/~meteor/ www.pkim.org/?q=en/ www.daa.fmph.uniba.sk/meteor_network http://www.imtn.it
A2. Fireball detection stations
It is usual to gather several cameras that patrol the sky from the same location. These stations are usually operated by professional researchers. For instance the Fireball
Research Group of the UCM is part of the Spanish Meteor Network ( SPMN ) (J.M.
Madiedo et al. 2009 , “ The Spanish Meteor Network (SPMN): full coverage of the Iberian
Peninsula by means of high-sensitivity CCD video devices
”, European Planetary
Science Congress 2009 , page 560.).
The Observatorio UCM is equipped with a Fireball
Detection Station consisting of 12 CCTV low-light cameras covering the whole sky during night and daytime (Field of View FOV=70 degrees). The result is all-sky coverage with a plate scale better than 7 arcmin/pixel, limiting magnitude up to magnitude 5 and a temporal resolution of 1/60s (de-interlaced). The station is described in detail in F. Ocaña et al., 2010 (“
Setting-Up a Fireball Detection Station at UCM
Observatory
”,
Proceedings of the International Meteor Conference 2010 ).

The equipment used is not very expensive. The cost of each camera with the lens and the casing is around 400€. Each camera needs a computer to process the video flux, but a low-end Intel Pentium 4 or AMD Athlon II microprocessor is enough. Discarded personal computers are used by amateur astronomers (at the time of writing this memo, the cost is less than 200€ per computer). However, the total budget to build and to keep working a complete station (several video cameras and computers) is high for an interested citizen.
A3. All-sky cameras
Single camera fireball stations are the simplest and cheapest unit of a network. The video camera should have a wide field of view close to all-sky view, i.e., the camera registers all the sky above the horizon. The device is build with a CCD video camera and a fish eye lens. The total cost of this system (including an enclosure) is around 60 euros. The setup and maintenance is very easy. This is way this method is preferred for interested citizens that wish to collaborate or for secondary schools outreach and research activities.
Examples of successful networks that use all-sky cameras are found in North America:

NASA All Sky Fireball Network (http://fireballs.ndc.nasa.gov/)

NMSU All Sky Camera Network (http://skysentinel.nmsu.edu/allsky/)

UWO All-Sky Camera Network (http://meteor.uwo.ca/all_sky.htm)
The all-sky camera of each node of the network registers all the visible sky over the site, but the astrometry accuracy of each single observation is poor. This is the drawback of these networks that could be solved when enough number of cameras is used. Despite its low resolution, many observations from several locations result in good orbital solutions. Also the lack of one station of the network (bad weather, failure, etc) is not noteworthy. This is a clear example of collaboration in an observational network: the scientific result (meteor orbit) is build with the help of all the available images obtained by the nodes.
Figure X. (Left) Detection of a bright meteor with a cheap all-sky camera built with a budget of less than 100 euros. (Center) Idem with a 250 euros colour camera. (Right) Idem with a professional grade all-sky camera (12 keuros).

Figure X. (Left) All-sky built with a CCTV board camera and a fisheye lens. (Right) Different kinds of enclosure to protect the camera against bad weather conditions.
Figure X. (Left) All-sky built with a ccd camera designed for amateur astronomy and a fisheye lens; the control is made with a cheap ARM based computer. (Right) The camera inside its enclosure over the rooftop of a building and aiming to the zenith.
4. By products
The detection software is based in changes of the image and the alarm that record a video clip of the event is activated in case of motion. The cameras that are settled to detect meteors are also recording events that the research groups are discarding as not interesting. For instance planes, balloons, satellites, and also flying animals as birds and bats, to name but a few.
4.1 Space surveillance
Satellites in Earth orbit could be monitored using different techniques: radar, radio, optical, etc. Amongst the optical observations, video monitoring has been proven to be successful for optical ground tracking allowing high temporal resolution (equivalent to good astrometry precision for these moving objects). Video-monitoring is already used for Space Surveillance purposes by amateur citizens. It is feasible to use this technique at Secondary School and University levels to increase the Educational Outreach of the space activities.

Ground optical and radar tracking suffer from some difficulties that can be overcome by a network of low cost cameras spread throughout Europe. The result of this synergy is the possibility of providing scientific data and media content for scientific divulgation (F.
Ocaña & J. Zamorano 2011, "
Space Surveillance Educational Outreach
– Video monitoring" in European Space Surveillance Conference 7-9 June 2011).
Satellite observing (for instance the International Space Station (ISS) visible passes across the sky) is an entertaining activity with a large educational potential, mainly in high courses and University. Furthermore, several classroom activities could be performed using data taken at the school's terrace roof. Video monitoring is a low cost technique to develop skills for basic astronomical observation and celestial mechanics calculations.
Using the adequate software each camera could detect tenths or hundredths of satellite events each night. The events registered are: a) Tumbling satellites that flare briefly (usually for less than a 0,1s) due to the lack of stabilization and lucky favourable geometric configuration (Sun satellite reflecting surface observatory). This kind of lucky detection increases the detection range of our system. Most of these satellites are always faint and under our equipment limit, but in the tiny fraction of second they flare. These objects are usually tumbling because operators have lost control and communication with them. Therefore its observation contributes to its monitoring. b) Satellite re-entries that usually consist of several objects travelling close together leaving a long trail when entering back into the Earth atmosphere. Its observation is crucial to determine the chance of the remnants to reach the ground. c) Satellite Launches, Fuel Dumps and Fast Satellites that can be recorded even far from launch facilities and before being inserted into the definitive orbit. d) Iridium and other Satellite Flares that could be used for Surface Modelling.
A4.2 Detection of flying fauna
Some of the detected events that are discarded by the researchers are animals flying in the field of view of the cameras. The video cameras for meteor detection are usually run during dark time, i.e., from dusk to dawn, due to high sensitivity of the detector. In this case the fauna detected is mainly composed of bats and nocturnal raptors. The video clips show distinct flight pattern, size and shape or silhouette that belongs to different kind of species and families (see for instance The Cornell Lab of Ornithology http://www.birds.cornell.edu/AllAboutBirds/birding123/identify/index_html). The video cameras easily detect birds and bats.

Figure X. (Left) Composite image with frame of the video record of the flight of a magpie in twilight.
(Right) Snapshot of a magpie taken with day light.
Figure X. (Left) Two frames of the flight of a barn owl detected with a video camera during a bright night with the Moon in the middle of the field of view. (Right) Two all-sky images obtained with a DSLR showing an owl perched on a chimney.
Bats are nocturnal mammals that are exposed to increasing levels of light pollution caused by anthropogenic land use changes. All bats of the temperate zone feed predominantly on insects. Since many insects are attracted to light, they accumulate around street lamps and thus represent a valuable and easy-to-access food source for bats. Thus, bats largely benefit from artificial light. Yet, some species seem to avoid foraging in artificial light. Consequently, we expect that the species composition of local bat assemblages is largely affected by artificial light (extracted from The Bat Lab at the
Leibniz Institute for zoo and Wildlife Research http://www.batlab.de/projects/bats-andlight-pollution/). Bat populations are one of the best natural indicators of the health of our environment (http://www.eurobats.org/).

Figure X. (Left) The flight of a bat is recorded in a video scene extracted from a camera that detects meteors. (Right) A meteor trail recorded with the same camera. Betelgeuse, a brighter star of the Orion constellation, has been marked on both images.
Many species of birds choose to migrate at night. Unfortunately for most bird watchers, millions of birds pass undetected through the night sky in the spring and fall as they make their journey between their breeding and wintering grounds.
Some studies of the nocturnal migration of birds are based on passage counts by amateur visual observers.
(See for instance Der Falke, Journal für Vogelbeobachter, special issue "Vogelzug" http://www.orn.mpg.de/3160729/Bird-migration_Falke_special_issue_2014.pdf). One known method used by the visual observers is to use a spotting scope or telescope to spot migrating birds as they pass across the full moon (Astronomy and Ornithology
Rense, W. A. Popular Astronomy, Vol. 54, p.55 1946PA...54...55R). Falta algo sobre la importancia de estudiar las migraciones de aves.
The birds flying in close formation are detected during bright nights, i.e., nights with
Moon over the horizon in dark sites or any night in places with moderate to severe light pollution. These events are recorded even with all-sky cameras and there is no need to use tracking telescopes or binoculars. Again the flight pattern and shape of the formation are clues to distinguish different families. Nighttime images of the Earth from satellites emphasize the degree of light-induced fragmentation of urban nightscapes, and could reveal potential migration barriers for nocturnal animals.

Figure X. (Left) The trail of migration birds in close formation over UCM Astronomical Observatory
(Ciudad Universitaria, Madrid). (Right) The V-shape of the flight in formation is clearly shown in another view of birds crossing Madrid (three frames composition).. The birds are visible thanks to the light pollution of the urban area.
When the camera use a CCD detector with the ability to integrate frames according to the brightness, it is possible to run the cameras day and night. During bright daytime the output is in colour while the integrated exposure at night yields video in black and white.
Finally, the all-sky cameras could also be used to record the cloud cover (day and night) and also to measure the night sky brightness and its evolution which is intimately related to light pollution.
B1. Introduction
Light Pollution is a multifaceted energetic and social problem that has a great impact on human health, economy, society and nature. The researchers in this field belong to different areas of expertise and their works are focused from many points of view. One of the main methods to measure Light Pollution from ground relies on its impact on the night sky brightness. The dark and starry skies of rural zones have been replaced by bright skies in urban areas near big cities.
The bright and polluted sky has astronomical, ecological, and human health effects.
This is why it is an emergent research topic with growing interest to citizens. For instance the International Dark Sky Association (IDA, http://darksky.org/) whose mission is 'to preserve and protect the night time environment and our heritage of dark skies through environmentally responsible outdoor lighting' has thousands of members distributed in 70 countries. Its "Globe at Night" program (http://www.globeatnight.org/) is an international citizen-science campaign to raise public awareness of the impact of light pollution by inviting citizen-scientists to measure their night sky brightness and submit their observations. Preliminary scientific results were published in "Citizen
Science Provides Valuable Data for Monitoring Global Night Sky Luminance" Christofer

C.M. Kyba et al. (2013) Scientific Reports 3, Article number: 1835 doi:
10.1038/srep01835.
Potentially interested partners around Europe:

LoNNe Loss of the Night Network (COST EU) http://www.cost.eu/domains_actions/essem/Actions/ES1204

ISTIL Istituto di Scienza e Tecnologia dell’Inquinamento Luminoso (Italy) http://www.inquinamentoluminoso.it/istil/

Verlust der Nacht (Germany) http://www.verlustdernacht.de/

REECL
Red Española de Estudios sobre la Contaminación Lumínica (Spain) http://guaix.fis.ucm.es/splpr/

RENOIR Ressources Environnementales Nocturnes, tOurisme, territoIRes
(France) http://renoir.hypotheses.org
There are many citizen associations fighting against light pollution in Europe. An incomplete list follows: Cel Fosc , Asociación contra la Contaminación Lumínica (Spain),
CieloBuio , Coordinamento per la Protezione del Cielo Notturno (Italy), ANPCEN ,
Association Nationale pour la Protection du Ciel et de l'Environnement Nocturnes
(France), ASCEN , Association pour la Sauvegarde du Ciel et de l'Environnement
Nocturnes (Belgium), CfDS , Campaign for Dark Skies de la British Astronomical
Association (BAA) (United Kingdon), ILPAC , Irish Light Pollution Campaign (Ireland),
Initiative gegen Lichtverschmutzung (Germany), DSS , Dark-Sky Switzerland,
Društvo
Temno nebo Slovenije (Slovenia).
B2. Night Sky Brightness
The brightness of the sky at night (NSB) depends on the phase and position of the
Moon for dark and unpolluted areas. The variation of the NSB is minimized near sources of light pollution where the night is brighter at any time. The effect of urban areas on NSB is apparent hundreds of km away. The best way to monitor and control light pollution consists in a network of photometers that measure NSB.
The Sky Quality Meter (SQM) is a commercial photometer designed to measure NSB in a photometric band that mimics the human eye response. This photometer is widely used by both professional researchers and amateur interested citizen. There are some networks of SQM photometers that provide measures of the NSB every night. For instance http://guaix.fis.ucm.es/splpr/SQM-REECL.
The analysis of the data provided by the photometers allows the researchers to monitor the nightly, monthly and yearly evolution of the NSB and the relationship with light sources of pollution in intensity and distance. Again the collaborative effort of many people provides the necessary data to derive scientific results. The photometers that are measuring in protected areas will alarm the researchers about eventual increasing of light pollution that could affect the environment.
There are more sophisticated devices to measure NSB that are too expensive and are

restricted to research groups. Between them the all-sky cameras equipped with fisheye and professional CCD camera and a filter set to determine the astronomical quality of the night sky (for instance AstMon, the Astronomical Monitor).
B3. Cheap photometers for NSB
To establish a node of a NSB network it is necessary to acquire a SQM photometer and connect it to a router or personal computer. The total price of this system, including the weather resistant housing, is around 300 euros. We are planning to design and build low-cost simplest photometers that could be widely distributed.
The prototypes of photometers that we are developing at UCM-LICA ("Advanced
Instrumentation Lab") are made of cheap filters, light collectors, detectors and other optical components that are easy to find in any place. The final designs will be tested and calibrated and distributed to the community as open hardware (or open source).
The researchers and also the interested people could acquire the parts and replicate the photometers from the instructions provided.
We plan to add new features for these photometers. Among them the capability to automatically send data to a repository located in a server, the autonomous operation with solar panels and batteries in remote places and the ability to measure in different spectral bands. The colour of the sky at night is related to the kind of luminaries that are contributing to the light pollution. A photometer with selected colour filters could distinguish between High Pressure Sodium (HPS), Metal Halide (MH) or Mercury
Vapour (MV) lamps to name the most important contributors.
Figure X. (Left) Prototype of a portable night sky brightness photometer with four channels (R, G, B, and clear). From left to right: The filter and collector view from top; side view with the detector in place; the boxes containing the optics and the electronics being tested at the optical lab.
B4. Cities at Night
Satellite images of the Earth taken at night help us to measure light pollution. We have shown that the pictures taken by astronauts on board the International Space Station
(ISS) can be calibrated and thus they are useful to perform scientific studies.
Furthermore, the colours of the images inform us of the lamps used and measuring the radiance get insight into the efficiency of lighting in many cities on the planet.
Most of the images taken by astronauts since 2003 have not been published and they

are archived into the repositories ("The Gateway to Astronaut Photography of Earth", http://eol.jsc.nasa.gov/) waiting to be used for research. Cities at Night is a tool for scientific and educational research (citizen science project) designed to browse the database in order to find interesting pictures, to classify them and identify the locations of the images to create maps of light pollution (http://www.citiesatnight.org/). This collaborative effort will help governments and local authorities to make the right decisions to reduce light pollution.
Figure X. Nocturnal pictures of European cities. Images courtesy of the Earth Science and Remote
Sensing Unit, NASA Johnson Space Center.

Figure X. Geo referenced images of Valencia (left) and Madrid (right) from Cities at Night project. Images courtesy of the Earth Science and Remote Sensing Unit, NASA Johnson Space Center.
The project is already running under the CrowdCrafting platform with the help of
Medialab Prado. The initial 135019 pictures that were included in the first phase have already been classified by at least 5 independent volunteers. Up to now, more than
16000 interested citizens have contributed.
Some resources should be dedicated to the follow up of this successful project. In particular there are pending tasks related to the software. For instance we should increase the user friendliness of the applications and the results of citizen work should be available almost in real time. They should be multiplatform. Being Cities at Night an interactive project we should allow the user to participate: an on-line forum to post comments, guidelines, feedback and facilitate discussion should be set up. On the hardware side, there is a need of the infrastructure that could serve input data and results.
The images selected by this project are very well suited to develop games of many kinds to learn geography for instance and they are very useful to concern people about light pollution. But they are also scientific data. We plan to develop the scientific reduction pipeline to process, calibrate and measure the geo-referenced images for their scientific exploitation.
C1. Introduction
Meteorology is probably the science that has attracted more interested citizens. The weather networks increase the number of members everyday. They wish to setup a personal weather station at home and share the data. For instance the US Citizen
Weather Observing Program (CWOP, http://wxqa.com/) is a volunteer-based network that allows owners of personal weather stations to share their station’s live data with the
National Weather Service (NWS), and other services. The data is ingested into meteorological databases. Another worldwide weather service that uses amateur data is
Weather Underground (http://www.wunderground.com/) with more that 37,000 personal weather stations linked to the network. Similar weather network exits in Europe countries as Meteoclimatic (http://www.meteoclimatic.net/) in Spain (incluir una lista de asociaciones de aficionados en Europa)
Besides this natural interest in weather, people are worried with the results of the climate change research and they would wish to make a contribution. However this research is based in long series of observations that need to be compared to models to extract statistical significant results. However, extreme weather events (a result of rare and unusual weather conditions) are observational results that are useful input data for

the computer model simulations. These events are usually located in a small region and they last a short time. This is why a dense network of personal weather stations increases the probability of recording, i.e., dismisses the lost of useful data.
C2. Weather observations
Satellite imagery and the weather stations reports are the weather information that is used for weather forecast. The stations are settled, maintained, and operated by the national meteorological services as

UK Met Office http://www.metoffice.gov.uk/

Meteo France http://www.meteofrance.com/

Deutscher Wetterdienst http://www.dwd.de/

Servizio Meteorologico http://www.meteoam.it/

Danish Meteorological Institute DMI

Estonian Environmental Agency EEA

Finnish Meteorological Institute FMI

Icelandic Meteorological Office VI

Irish Meteorological Service Met Eireann

Royal Netherlands Meteorological Institute KNMI

Norwegian Meteorological Institute MET Norway

Spanish State Meteorological Agency AEMET

Swedish meteorological and Hydrological Institute SMHI

Lithuanian Hydrometeorological Service LHMS
Many of them are members of the international research programme HIRLAM (HIgh
Resolution Limited Area Model, http://www.hirlam.org/), a research cooperation of
European meteorological institutes.
C3. Personal weather stations
The weather stations operated by the national services provide reliable atmospheric conditions since their equipment have been carefully calibrated. A large suite of instruments is used to record the weather data. On the other hand, personal weather stations are usually a reduced set of the main measuring instruments or sensors
(thermometer, hygrometer, barometer, anemometer and pluviometer).
A fraction of the weather stations owned by citizens are willing to obtain and share accurate data that could be comparable. In this case they care for the quality and placement of the instruments and they acquire 'professional' quality weather stations.
There are so many options in the market that "What weather station should I buy?" is the most popular question found in amateur weather forums.
Custom made weather stations built from individual sensors is an alternative to the off the shelf complete weather stations. This approach allows adding specific sensors as cloud and night sky brightness sensors for Astronomy observations, or air quality sensors for air pollution monitoring to name only two examples.

Figure X. (Left) Consumer grade or home weather station. (Middle) Off the shelf weather station more rugged and reliable. (Right) Custom-made weather station made by adding together sensors acquired from different companies.
C4. Developing affordable weather stations
We are planning to develop a simple and reliable weather station. The system should be open hardware and replicable everywhere. The basic module, including the typical sensors, could be upgraded with specific modules.
To reduce the budget, the mechanical parts will be taken from existing cheap parts or will be designed to allow to be made in plastic with 3D printing. The electronics and control software (open software) to run the weather station unattended will be also developed. Finally an Automatic Weather Station (AWS) version that could perform measurements in remote areas is also envisaged.
Our goal is to design a reliable weather station that could be built by interested citizens using the instructions provided but individuals could also buy an affordable out of the box station build by third interested partners.
It is expected that low budget weather stations could be easily disseminated between citizens and also clubs, associations and colleges. There is no need to emphasize the impact of a weather station in an educational centre were students could perform their first steps in scientific research.