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://math2.org/
Math2.org is a comprehensive math reference site offering organized tables, formulas, and identities covering everything from basic arithmetic to calculus, linear algebra, and Fourier transforms. Available in both English and Spanish, it also features a message board for math questions and links to other top math resources on the web.
https://www.qsl.net/w6ka
The W6KA Pasadena Radio Club is the official web presence for a California-based amateur radio club serving the Pasadena and Altadena area. The page serves as a gateway to the club's main sites and connects visitors to the Amateur Radio World Ring webring network.
https://mnrepeaters.org/
The Minnesota Repeater Council is the official coordinating body for amateur radio repeaters across Minnesota, maintaining frequency coordination, band plans, and membership records for ham radio operators statewide. Visitors can download the current MN repeater listing in multiple formats, access coordination forms, review access plans, and find meeting details including Zoom links for upcoming MRC sessions.
http://russsscope.net/staxtutorial.htm
A beginner-focused step-by-step tutorial for stacking and processing planetary images using the free software Registax, written by an astrophotographer who uses a Meade DSI Color camera. The guide walks through alignment, optimization, stacking, and wavelet sharpening in plain language, making it accessible to newcomers who find other tutorials too vague.
https://vkham.com/
VKHam is a comprehensive Australian amateur radio resource hub run by VK2CA, featuring over 12,000 QSL card images, a directory of 1800+ VK callsigns, repeater maps for all Australian states, and DX information. The site also offers kit and radio manuals, electronics resources, frequency tables, and a classifieds section specifically for the Australian ham radio community.
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://meteore.forumattivo.com/
The Italian Meteor and TLE Network (IMTN) is a national Italian surveillance network dedicated to observing and studying meteors, fireballs, and Transient Luminous Events (sprites, jets) in the upper atmosphere between 20 and 120 km altitude. Founded in January 2009, the network operates permanent and mobile video and radio stations around the clock, connecting university researchers, amateur astronomers, and scientific associations across Italy.
https://k3lr.com/
K3LR is the homepage of Tim Duffy's world-class amateur radio contest station, featuring a multi-operator, multi-transmitter setup that has been featured in QST, RadCom, and the Spectrum Monitor. The site showcases Team K3LR's competition activities, sponsored equipment from Icom and DX Engineering, and links to Dayton Contest University events.
https://isws.illinois.edu/statecli/cuweather
Maintained by the Illinois State Water Survey and State Climatologist Dr. Jim Angel, this site provides detailed climate data for Champaign-Urbana going back to 1996, including daily and monthly temperature, precipitation, snowfall, and degree day records. It's a rich archival resource for anyone researching Illinois weather history, with links to real-time conditions, airport hourly data, and regional precipitation networks.
https://atn-tv.org/
The Amateur Television Network (ATN) is a national organization for ham radio operators interested in amateur television transmission, with regional chapters across Arizona, California, Colorado, and beyond. The site features decades of meeting photos, repeater coverage maps, membership rosters, streaming events, and information on digital ATV technology.