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://concordiemborealis.blogspot.com/
Stephen Saber's Concordiem Borealis is a carefully curated observing list of 400+ deep sky objects and double stars for northern hemisphere astronomers, unifying targets from the Astronomical League's Messier, Caldwell, Bino Deepsky, and Double Star programs with the RASC's Finest NGC Objects. Organized by constellation with magnitude, coordinates, and Pocket Sky Atlas chart references, it serves as a practical field companion for observers working through official observing programs.
https://theastronomer.tripod.com/
Tammy Plotner's astronomy site is a sprawling personal observatory journal covering years of nightly observing reports, constellation starhop guides, solar and lunar photography, aurora sightings, and deep sky sketches. With content spanning from 2001 to 2007 and sections on Messier studies, planetary transits, and star parties across Ohio and beyond, this is a genuine labor of love for backyard astronomers.
https://www.qsl.net/mara/index.html
The Madison Area Repeater Association (MARA) is a non-profit amateur radio club based in Madison, Wisconsin, affiliated with the Wisconsin Association of Repeaters. This page serves as a hub for club members, listing meeting times and locations while redirecting visitors to their newer site.
http://capitalastronomers.org/
The National Capital Astronomers is a Washington D.C. metro area nonprofit astronomy club founded in 1937 at the US Naval Observatory, offering monthly star talks, public telescope events at Rock Creek National Park, and science fair outreach programs. Members and visitors can find meeting lecture videos, telescope-making workshop info, stargazing tips, and membership details for this long-running amateur astronomy society.
https://complex-analysis.com/
Created by Juan Carlos Ponce Campuzano, this interactive online textbook introduces complex analysis through visual applets built with GeoGebra, p5.js, and other JavaScript tools, making abstract mathematical concepts tangible and explorable. Covering topics from the Cauchy-Goursat Theorem to conformal mappings, it serves engineering and mathematics students with a beautifully designed, continually updated resource that includes Spanish and Italian translations.
http://redcircuits.com/
RED Free Circuit Designs is a hobbyist electronics resource offering dozens of free audio amplifier schematics, preamplifier modules, headphone amplifiers, and miscellaneous electronic circuit designs. Visitors can browse Class-A and Class-B amplifier projects, phono preamps, intercom circuits, and many more practical designs, all available at no cost.
https://castfvg.it/galassie/indexgal.htm
An extensive galaxy catalog reference compiled by the Circolo Astrofili Talmassons (C.AS.T.), an Italian astronomy club, featuring member-photographed images organized across major catalogs including NGC, UGC, IC, PGC, Messier, and VCC. The site covers thousands of galaxies alongside deep sky objects, quasars, and galaxy clusters, making it a remarkable visual archive built collaboratively since 1996.
http://nationalcurvebank.org/
The National Curve Bank is a mathematical archive dedicated to cataloging and exploring curves, offering detailed information on their properties, equations, and historical significance. A sister site to the Witch of Agnesi page, this project serves as an educational reference for students, educators, and math enthusiasts interested in the geometry of curves.
https://unifiedmicro.com/
Unified Microsystems is a small company specializing in amateur radio hardware and electronic development products, including CW keyers, receive antenna systems, sound card interfaces, and Arduino shields. Their product catalog serves ham radio operators and electronics hobbyists with unique kits and modules available through authorized dealers like DX Engineering and Ham Radio Outlet.
https://copaseticflow.blogspot.com/
Copasetic Flow is a technically rich blog blending amateur radio operations with hands-on software experiments, covering topics like POTA activations, antenna comparisons, QSO logging, and ionogram analysis. The author also documents AI and programming experiments with tools like ChatGPT, Codex CLI, and the Whisper API, making it a fascinating intersection of ham radio and modern tech tinkering.