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://wordwizz.com/pwrsof10.htm
Bruce Bryson's 'Quarks to Quasars' takes visitors on a visual journey through the universe using powers of ten, spanning from subatomic particles smaller than 10^-18 meters to the observable cosmos at 10^26 meters. With nearly 200 pages of original drawings and images, each step in scale reveals ten times more or less of the universe, making it a deeply immersive and educational exploration of cosmic scale.
https://n0ofq.tripod.com/
N0OFQ is a ham radio operator based in Yutan, Nebraska who runs a 145.37 MHz repeater linked to stations across the region. The page features an interactive world time map, repeater frequency details, over 4000 ham radio links, and participation in the Amateur Radio Webring.
http://uksmg.org/content/deadband.htm
Written by Palle Preben-Hansen (OZ1RH), this technical article explains how radio amateurs can make long-distance contacts on the 50MHz (Six Meter) band by exploiting meteor scatter propagation even when the band appears dead. It covers meteor trail geometry, shower timing, diurnal and seasonal meteor rate variations, and practical operating techniques, with supporting figures and links to software and IARU procedures.
https://mysterium.com/extinction.html
Created by David Ulansey, this long-running reference site compiles hundreds of links to authoritative scientific reports documenting the ongoing sixth mass extinction and global biodiversity crisis. Active since 1998 and last updated in 2021, it covers species loss across vertebrates, insects, plants, and freshwater animals, drawing on sources like the IUCN, UN, WWF, and major scientific journals.
https://w4zt.com/
Tony King's W4ZT memorial site covers his extensive amateur radio activities, including repeaters, antenna construction, power supply modifications, and DXpeditions. Now preserved as a tribute after Tony's passing in 2009, the site offers a wealth of technical resources and personal projects from a dedicated ARRL life member based in the Atlanta area.
https://rammb-data.cira.colostate.edu/tc_realtime
Run by NOAA's Regional and Mesoscale Meteorology Branch at Colorado State University, this site tracks currently active tropical cyclones worldwide in real time using satellite imagery and meteorological data. Researchers and weather enthusiasts can browse live storm data, archived seasons going back to 2006, and products developed by NESDIS/STAR/RAMMB scientists.
https://empslocal.ex.ac.uk/people/staff/mrwatkin
Matthew R. Watkins is a mathematician and honorary researcher at Exeter University whose site centers on his celebrated 'Secrets of Creation' trilogy, making analytic number theory and prime numbers accessible to general audiences. The site also features a number theory and physics archive, prime number resources for beginners, and links to his eclectic range of interests including parapsychology, the I Ching, and psychogeography.
https://dxmaps.com/spots/mapg.php?Lan=E
DXMAPS is a real-time interactive mapping tool for amateur radio operators, displaying live QSO contacts and SWL spots across multiple bands and propagation modes worldwide. Visitors can filter by frequency band, propagation type (Sporadic-E, Aurora, EME, Tropo, F2, and more), region, and data source including DX-Cluster and PSK Reporter, making it an invaluable tool for DXers and ham radio enthusiasts.
https://www.qsl.net/k6ls/test.html
Phil (K6LS) has assembled an extensive directory of links to test and measurement equipment manufacturers, dealers, and related resources for amateur radio and electronics hobbyists. The collection spans commercial makers like Tektronix, Fluke, and Rohde & Schwarz alongside used equipment dealers, repair services, and homebrew resources, making it a useful reference for anyone sourcing or servicing RF test gear.
http://kc7nod.20m.com/index.htm
CW's radio page is a hobbyist resource dedicated to shortwave listening, featuring DIY projects and guides for devices like random wire antennas, static discharge units, ferrite couplers, and attenuators. The site offers practical technical content for SWL enthusiasts, including modification guides for receivers like the DX 390 and transformer builds.