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)
http://normsrotorservice.com/
Norm's Rotor Service is the oldest and largest antenna rotator repair facility in the United States, specializing in sales, service, and parts for ham radio antenna rotators since the 1960s. With an inventory of over 25,000 parts covering brands like Cornell-Dubilier, Hy-Gain, and Telex, this is an essential resource for amateur radio operators needing rotor repairs or replacements.
https://hexkit.com/
Ron Mott (W4RDM) runs HexKit.com, a small operation fabricating baseplate kits, hubs, and components for homebrew Hex Wire Beam, Moxon, and Spiderbeam amateur radio antennas. Over 1,700 homebrew hex beam builds have used HexKit baseplates worldwide, making this a well-regarded niche resource for DIY antenna builders.
http://celestrak.org/
CelesTrak, maintained by T.S. Kelso, is a premier resource for satellite tracking data including NORAD GP element sets, two-line element (TLE) files, and orbital environment tools used by the global space community. Now operating as a 501(c)(3) non-profit, it offers visualization tools, SOCRATES conjunction analysis, documentation, and special event coverage including debris events and rocket body reentries.
https://thecosmarnaut.neocities.org/
Mars, a 20-something university student, built this space-themed personal site called The Observatory as both a creative outlet and a first coding project. The site features personal pages covering favorites, original characters, and infodumps, all wrapped in a stargazing aesthetic with pixel art and a love of space at its heart.
https://astronomy-links.net/twocomets.html
Clark M. Thomas offers a detailed analysis of comet imaging techniques, comparing amateur astrophotographer Damian Peach's stunning wide-field ISON image against the professional Subaru telescope's shot of Comet Lovejoy. The article makes a compelling case for tracking background stars rather than the comet itself, arguing that the resulting sharp stellar fields and visible deep-sky objects produce the most visually rewarding comet photographs.
https://m0yng.uk/
Christopher M0YNG is a radio amateur based in Gloucestershire whose personal site covers amateur radio, solar and battery tracking, self-hosted tech, and small computing projects like the Penkesu Tiny Computer. The site is notably available via Gopher, Gemini, and Tor in addition to HTTP, making it a fascinating example of smolnet philosophy in practice.
https://www.qsl.net/w4bkm
A QSL.net-hosted page for amateur radio operator W4BKM, part of the well-known ham radio community hosting platform. The site appears to be a personal station page, accessible through the QSL.net directory which is dedicated to ham radio operators worldwide.
https://chemguide.co.uk/index.html
Chemguide, created by Jim Clark, is a comprehensive chemistry reference site aimed at helping students aged 14 through A-level understand topics ranging from atomic structure and bonding to organic reaction mechanisms and physical chemistry. Covering major UK exam syllabuses including GCSE, CIE Cambridge International, and Edexcel, it serves as an authoritative free study aid with deep topic coverage across all major chemistry disciplines.
http://astroverde.org/
Astroverde is the official website of the Astronomers of Verde Valley, an amateur astronomy club based in Northern Arizona's Verde Valley region. Visitors can browse member astrophotography galleries, find star party schedules, access observing tools, and learn how to join the club.
https://kk4das.blogspot.com/
KK4DAS is a ham radio blog by an enthusiastic homebrew builder documenting the construction of transceivers, antennas, and test equipment from scratch. Posts dive deep into technical details like crystal ladder filters, diode ring mixers, and VFO modules, making it a treasure trove for QRP and homebrew radio enthusiasts.