Science & Nature
1439 sites
Subcategories:
- Astronomy & Space (396)
- Chemistry (8)
- Earth Sciences (26)
- Biology (79)
- Physics (30)
- Mathematics (59)
- Weather & Climate (104)
- Amateur Radio (682)
- Electronics (47)
https://sites.uni.edu/morgans/astro/course/Notes/section2/spectralmasses.html
A detailed reference table from a university astronomy course listing spectral types of stars across main sequence, giant, and supergiant classifications, with corresponding temperature, absolute magnitude, luminosity, and mass values. Covering everything from scorching O5 stars down to cool T8 brown dwarfs, this page serves as a compact but comprehensive stellar classification resource for students and enthusiasts alike.
http://mathres.kevius.com/art.html
Bruno Kevius has assembled an extensive link collection covering mathematical art, fractals, chaos theory, and geometry, featuring resources on M.C. Escher, polyhedra, cellular automata, and fractal software. With over 120 curated links spanning strange attractors, tessellations, origami, and geometric sculpture, this is a rich reference hub for anyone exploring the intersection of math and visual art.
https://www.qsl.net/w1aa/w1aa_1001.htm
Documenting the 2003 Marconi 100th Anniversary Special Event station operated by the Marconi Radio Club (W1AA) and the Marconi Cape Cod Memorial Radio Club (KM1CC) near the historic Cape Cod transmission site, this site captures a milestone commemoration that logged over 13,000 contacts worldwide. Highlights include a rare contact with the International Space Station and a presidential commemorative message from George W. Bush, making it a fascinating record of amateur radio history in action.
https://nerepeaters.com/
The New England Repeater Directory (NERD) is a volunteer-maintained database of amateur radio repeaters across the New England region, updated nightly to ensure accuracy. Visitors can search listings by location and band, plot results on Google Maps, and download the full database as a CSV file for use with radio programming software.
http://aberdeenastro.org.uk/
The Aberdeen Astronomical Society (AAS) is a Scottish astronomy club based in Aberdeenshire, hosting regular meetings, dark sky observing sessions, and public talks both in person and via Zoom. The site features aurora photography by members, an interactive star chart for Aberdeen, upcoming event listings, and a night sky section covering visible astronomical events from the local area.
https://www.qsl.net/w4frc
The Ft. McCoy Amateur Radio Club (W4FRC) is a friendly ham radio club based in the Ocala National Forest area of Marion County, Florida, founded in October 1997. The site shares club meeting info, VE testing schedules, member photos, and an open invitation for newcomers to discover the hobby of amateur radio.
https://qsl.net/5b4es
The English School Radio Club (callsign 5B4ES) is a school-based amateur radio club founded in 1969 in Cyprus, covering contesting, licensing exams, and hands-on operator training for new members. The site offers history, exam notes, channel statistics, a photo library, and news about club events, making it a genuine hub for young ham radio enthusiasts.
https://handprint.com/ASTRO/bortle.html
A detailed reference page explaining the Bortle Dark Sky Scale, which measures night sky light pollution across nine categories from inner-city skies to pristine darkness. The site includes an adapted table of Bortle's indicators with color codes used in light pollution maps, plus five star charts covering key sky areas visible from the continental United States.
https://chinalakeastro.org/
The China Lake Astronomical Society (CLAS) is a community astronomy club based in Ridgecrest, California, taking advantage of some of the darkest skies in the United States near Death Valley. The site offers information on monthly meetings, star parties at their dark sky site on Brown Road, newsletters, and membership for skywatchers in the Indian Wells Valley.
https://www.shreveportastronomy.com/
The official website of the Shreveport-Bossier Astronomical Society, a non-profit astronomy club active in Louisiana since 1959, offering free public observing nights, access to the historic Shreveport Observatory, and resources covering astrophotography, variable star observation, and more. Visitors can find meeting schedules, membership info, observing certificates, and a curated list of astronomy links ranging from NASA to Sky and Telescope Magazine.