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://qsl.net/aa3rl/ant2.html
Mike Banz (AA3RL) breaks down the technical question of dipole antenna height with detailed radiation pattern analysis, helping amateur radio operators choose the right height for DX work, local nets, or directional operation. The page features multiple elevation pattern plots comparing dipole performance at various heights, making it a practical reference for hams planning their antenna installations.
https://planetary.chem.tufts.edu/Phoenix/index.html
A page dedicated to NASA's Phoenix Mars Scout Mission, hosted on a Tufts University chemistry server, featuring launch videos including a close-up NASA recording and a team footage from Cocoa Beach in August 2007. It offers a glimpse into the excitement surrounding the Phoenix lander's launch, which went on to study the Martian arctic soil.
https://naa.net/
The Nürnberger Astronomische Arbeitsgemeinschaft (NAA) is a German astronomy club based in Nuremberg that operates the Regiomontanus Observatory, offering public sky tours twice a week and maintaining a library of over 1600 books. The site covers club activities, upcoming events, an astronomical image gallery, and the club's own journal 'Regiomontanusbote', making it a rich hub for amateur astronomy in the Nuremberg region.
https://members.tripod.com/~Hamnut_2/index.htm
Larry Miller (KB5ITT) shares his adventures installing ham radio repeaters on mountain peaks in the San Juan Mountains of southwestern Colorado, blending technical radio work with exploration of ghost towns and scenic four-wheeling routes. The site covers two specific mountain-top repeater builds near Silverton, historical photography of old mining towns like Animas Forks, and off-road trail information for the region.
https://projectpluto.com/
Project Pluto offers a suite of astronomical software tools for both amateur and professional astronomers, including the well-known Find_Orb orbit determination software, Sat_ID for identifying artificial satellites, and the Guide star charting DVD. The site provides free online versions of many tools alongside downloadable software, C/C++ source code, and reference resources like lunar phase calendars and asteroid observer tools.
http://heavens-above.com/
Heavens-Above, developed by Chris Peat, provides real-time satellite tracking and pass predictions customized to your exact location, covering the ISS, Starlink, Hubble, and hundreds of other spacecraft. Beyond satellites, the site offers interactive sky charts, solar eclipse data, comet and asteroid tracking, and deep space mission information, making it an essential tool for backyard astronomers and satellite spotters alike.
http://setileague.org/
The SETI League is a nonprofit membership organization dedicated to the privatized electromagnetic search for extraterrestrial intelligence, coordinating amateur radio astronomers worldwide in the hunt for signals from other civilizations. The site offers extensive technical resources covering antennas, receivers, and software, alongside publications, press releases, and the popular "Ask Dr. SETI" column.
http://nrrt.org/
The Newton Radio Response Team is a community emergency communications group based in Newton, likely coordinating amateur radio operators for public safety and disaster response. Sites like this serve as a hub for volunteer ham radio operators who support local emergency services when standard communications fail.
https://trac.org.tr/
TRAC (Türkiye Radyo Amatörleri Cemiyeti) is the official national amateur radio society of Turkey, founded in 1962, serving licensed ham radio operators across the country with regional chapters and representatives. The site offers callbook lookups, VHF/UHF contest results, QSL bureau services, repeater information, EchoLink and APRS guides, and resources for obtaining an amateur radio license in Turkey.
https://farcircuits.net/
Far Circuits is a long-running manufacturer and supplier of printed circuit boards designed specifically for amateur radio and electronics hobbyist projects, operating out of Dundee, Illinois for over 35 years. Visitors can browse and order boards organized by category including audio amps, frequency standards, converters, keyers, battery chargers, and direction-finding projects, with ordering handled through PayPal.