Astronomy - General

Wikipedia – Astronomy – Concise encyclopedia overview of astronomy’s branches, history, and major discoveries.

Space.com – What Is Astronomy? – Popular-science article surveying the key fields of modern astronomy and how amateurs and professionals explore the cosmos.

Space Elevators & Astronomy (Elevators.com) – Introductory essay on space-elevator concepts plus curated links to general astronomy resources. Suggested by Dorothy Mayer and her student Mila (who found this link)- thanks for the great addition!

Astronomy Publications - Magazines and Periodicals

Sky & Telescope – Flagship U.S. monthly packed with observing guides, gear tests, and peer-reviewed news from professional astronomy. 

Astronomy Magazine – Popular-science glossy that mixes breaking research, night-sky charts, and equipment columns for hobbyists of every level. 

BBC Sky at Night Magazine – UK companion to the world’s longest-running TV show, featuring how-to imaging projects, gear reviews, and interviews. 

Astronomy Now – Britain’s oldest monthly astronomy title (since 1987), noted for in-depth instrument reviews and practical observing articles. 

StarDate Magazine – Bi-monthly sky-watching guide from McDonald Observatory, famed for concise almanacs and accessible astronomy features. 

Amateur Astronomy Magazine – Quarterly, reader-written journal showcasing projects, star parties, and wide-field imaging from the global amateur community. 

The Planetary Report – The Planetary Society’s colorful quarterly spotlighting planetary science, mission updates, and citizen-science advocacy. 

Mercury Magazine – Astronomical Society of the Pacific’s digital quarterly blending astronomy research, education, and outreach stories (free PDFs for members; select articles open). 

Astronomy Technology Today – Free online magazine focused on hardware: detailed telescope, mount, and accessory reviews plus DIY upgrades. 

Journal of the AAVSO (JAAVSO) – Peer-reviewed quarterly publishing original variable-star research by amateurs and professionals (all issues free online). 

Astrobites – Daily “research digest” blog summarizing new papers on astro-ph; written by grad students for undergrads and advanced amateurs.  Black Holes

NASA Science – Black Holes – NASA’s authoritative overview of black-hole types, formation, and detection methods.

1440 – Black Holes Explained – Accessible summary of black-hole science, recent discoveries, and educational resources.

Black Hole – Wikipedia – Comprehensive reference article covering black-hole physics, observational evidence, and theoretical models.

Atlases & Star Charts

Historical

Linda Hall Library – Digital Star Atlases Collection – High-resolution scans of landmark works such as Bayer’s Uranometria (1603), Hevelius’s Firmamentum Sobiescianum (1690), Bode’s Uranographia (1801), and Cellarius’s Harmonia Macrocosmica (1660). 

Bayer Uranometria (1603) – David Rumsey Map Collection – The first atlas to chart the entire celestial sphere; all 51 engraved constellation plates viewable and downloadable in full detail. 

Flamsteed Atlas Coelestis (1729) – OU Digital Collections – Complete folio plates from the first modern star atlas based on telescopic positions, freely browsable online. 

Bode Uranographia (1801) – Archive.org Facsimile – Monumental 20-sheet atlas plotting 17,000+ stars and boundary lines for every constellation; considered the last of the great pictorial star atlases. 

Burritt’s Geography of the Heavens Atlas (1856) – Beautiful hand-colored constellation maps that popularized star-gazing in 19th-century America; full atlas hosted by the Library of Congress. 

Hevelius Firmamentum Sobiescianum (1690) – AtlasCoelestis Mirror – Digital plates from Hevelius’s post-humous atlas introducing 11 new constellations and exquisite artistic engravings. 

Linda Hall Library – Digital Star Atlases Collection – High-resolution scans of landmark works such as Bayer’s Uranometria (1603), Hevelius’s Firmamentum Sobiescianum (1690), Bode’s Uranographia (1801), and Cellarius’s Harmonia Macrocosmica (1660). 

Bayer Uranometria (1603) – David Rumsey Map Collection – The first atlas to chart the entire celestial sphere; all 51 engraved constellation plates viewable and downloadable in full detail. 

Flamsteed Atlas Coelestis (1729) – OU Digital Collections – Complete folio plates from the first modern star atlas based on telescopic positions, freely browsable online. 

Bode Uranographia (1801) – Archive.org Facsimile – Monumental 20-sheet atlas plotting 17,000+ stars and boundary lines for every constellation; considered the last of the great pictorial star atlases. 

Burritt’s Geography of the Heavens Atlas (1856) – Beautiful hand-colored constellation maps that popularized star-gazing in 19th-century America; full atlas hosted by the Library of Congress. 

Hevelius Firmamentum Sobiescianum (1690) – AtlasCoelestis Mirror – Digital plates from Hevelius’s post-humous atlas introducing 11 new constellations and exquisite artistic engravings. 

Free Digital Star Atlases (Printable / Interactive)

TriAtlas Project (A, B & C Sets) – 300-page PDF atlas series (to mag 12.6) offering wide-field, intermediate, and ultra-detailed charts—excellent all-sky companion for deep-sky observers. 

Deep-Sky Hunter Star Atlas – 110 printable A3 charts down to mag 10.2 (stars) and mag 14 (DSOs) plus 21 zoom maps of galaxy clusters; ideal for serious visual sweeps. 

Taki’s 8.5-Magnitude Star Atlas (PDF) – 146 A4 charts plotting stars to mag 8.5 and 2,900+ DSOs—lightweight but deeper than most commercial pocket atlases. 

Mag-7 Star Atlas – Free, printer-friendly charts to mag 7.25 with 550 deep-sky objects—great grab-and-go atlas for binocular or small-scope sessions. 

Pretty Deep Maps – Hyper-linked PDF atlas covering the entire sky to about mag 18, with 6,700+ charts and 100k-object index for image-identification and planning. 

Skymaps.com – Monthly Evening Sky Map – Free PDF star chart issued each month for northern, equatorial, and southern latitudes, annotated with current planet/comet positions and observing highlights. 

Book Recommendations

Astronomy

Turn Left at Orion, 5th Ed. – Classic sky‐hopping guide showing exactly how 100 + objects appear in a small backyard scope and how to find them. 

NightWatch, 5th Ed. – Best-selling beginner’s handbook with seasonal star charts, equipment tips, and binocular/telescope targets. 

The Backyard Astronomer’s Guide, 4th Ed. – Photo-rich reference covering gear, observing, astrophotography basics, and planning under any budget. 

Astronomy: A Self-Teaching Guide, 8th Ed. – Step-by-step workbook that builds core concepts from seasons and phases to cosmology. 

The Stars: A New Way to See Them – H.A. Rey’s constellation guide with friendly line drawings and year-round sky maps. 

Deep-Sky Wonders – Sue French’s beloved tour of 100 + deep-sky showpieces and hidden gems from her Sky & Telescope columns. 

Observing Handbook & Catalogue of Deep-Sky Objects – Detailed visual guide to 2,500 galaxies, clusters, and nebulae for serious observers. 

Annals of the Deep Sky, Vol. 1 – In-depth essays blending history and astrophysics for notable stars and DSOs, first of an ongoing reference series. 

Cosmos – Carl Sagan’s timeless, richly illustrated narrative of cosmic evolution and humanity’s place within it. 

Astrophysics for People in a Hurry – Neil deGrasse Tyson distills big-bang-to-black-hole science into brisk, witty chapters. 

The Fabric of the Cosmos – Brian Greene’s lucid tour of relativity, quantum mechanics, and the true nature of space-time. 

Cambridge Photographic Atlas of Galaxies – 250 beautifully imaged galaxies with explanatory text and observing tips for each. 

History of Astronomy

Coming of Age in the Milky Way – Timothy Ferris’s award-winning chronicle of how human ideas about the cosmos evolved from ancient Greece to modern cosmology. 

The Sleepwalkers: A History of Man’s Changing Vision of the Universe – Arthur Koestler’s sweeping narrative of the scientific revolution from Copernicus to Newton and how “sleepwalking” geniuses reshaped our worldview. 

The Copernican Revolution – Thomas S. Kuhn’s classic analysis of the 16th-century upheaval that moved Earth from the cosmic center and sparked modern science. 

Longitude – Dava Sobel’s riveting account of John Harrison’s clocks and the 18th-century quest to solve the “longitude problem,” blending navigation, astronomy, and politics. 

The Glass Universe – Dava Sobel highlights the “Harvard Computers,” the women whose photographic-plate work revolutionized stellar astronomy at the turn of the 20th century. 

The Day We Found the Universe – Marcia Bartusiak tells the dramatic story of Edwin Hubble, the Hooker telescope, and the discovery that the universe is far larger than the Milky Way. 

A More Perfect Heaven – Dava Sobel’s dual biography/play depicting how Copernicus’s De revolutionibus finally saw print and upended 1,500 years of geocentric thought. 

Finding Our Place in the Universe – Hélène Courtois narrates the modern quest that mapped the Laniakea super­cluster and pinpointed the Milky Way’s “address” in the cosmic web. 

Big Bang – Simon Singh’s lively history of how scientists pieced together the story of the expanding universe—from ancient philosophers to cosmic-microwave discovery. 

Chasing Venus: The Race to Measure the Heavens – Andrea Wulf recounts the 18th-century global expeditions to observe Venus transits and calculate the scale of the solar system. 

Galileo’s Daughter – Dava Sobel weaves Galileo’s scientific triumphs and Inquisition ordeal with the intimate letters of his cloistered daughter, Sister Maria Celeste. 

Historic Observatories

The Perfect Machine: Building the Palomar Telescope – Ronald Florence’s page-turner on George Hale’s 20-year quest to erect the 200-inch “Big Eye” on Palomar Mountain and how it ushered in Big Science. 

First Light: The Search for the Edge of the Universe – Richard Preston’s lyrical portrait of the astronomers and breakthrough discoveries made with the Hale and early Keck telescopes. 

Cosmic Odyssey: How Intrepid Astronomers at Palomar Observatory Changed our View of the Universe - Astronomer Linda Schweizer tells the story of the men and women at Palomar and their efforts to decipher the vast energies and mysterious processes that govern our universe. Suggested by David Kreiton

Yerkes Observatory, 1892-1950 – Donald Osterbrock chronicles the rise, near-closure, and revival of the “birthplace of modern astrophysics” and its record-setting 40-inch refractor. 

The Monster Telescopes, Erected by the Earl of Rosse, Parsonstown – Facsimile of an 1844 contemporary account detailing construction of the 72-inch “Leviathan” that first revealed spiral galaxies. 

The Story of Jodrell Bank – Sir Bernard Lovell’s insider memoir of designing, funding, and saving the 76 m radio dish that tracked Sputnik and found the first binary pulsar. 

The Arecibo Observatory: A History of Innovation and Discovery – Former director Donald Campbell tells the full saga of the iconic 305 m radar dish—from Cold-War origins to Nobel-winning science. 

The Day We Found the Universe – Marcia Bartusiak recounts Edwin Hubble’s use of Mt. Wilson’s 100-inch Hooker telescope to prove other galaxies and cosmic expansion. 

Mount Wilson Observatory: Breaking the Code of Cosmic Evolution – Allan Sandage’s authoritative, richly illustrated history of the solar and stellar work that made Mount Wilson the world’s premier observatory in the early 20th century. 

Eye on the Sky: Lick Observatory’s First Century – Osterbrock, Gustafson & Unruh weave human stories and scientific milestones of America’s first mountaintop observatory. 

James Lick’s Monument: The Saga of Captain Richard Floyd and the Building of the Lick Observatory – Helen Wright’s engaging narrative of the 19th-century engineering feat that placed a 36-inch refractor atop Mount Hamilton. 

Constellations

StarChild – List of 88 Constellations – Simple table of Latin and English constellation names.

https://astronomy.swin.edu.au/cosmos/c/Constellation - list of constellations and where they came from.

Constellation-Guide – Hemisphere Star Maps – Simple north- and south-sky charts showing every constellation outline.

Constellations & Mythology – Overview – Accessible primer on the stories behind the constellations. A nice summary of constellation methodology and information for those interested in learning more. Bought to my attention by a reader - thanks, Stacy

Cosmology

https://discover.join1440.com/topics/big-bang - 1440’s overview of concepts around the Big Bang!

WMAP “Introduction to Cosmology” (NASA) – Clear primer on the Big Bang, cosmic evolution, and observational evidence, maintained by the WMAP science team

WMAP “Universe 101” – NASA – A clear, jargon-free primer that walks readers through the Big Bang, cosmic expansion, dark matter/energy, and the Universe’s ultimate fate, with interactive graphics and glossary. 

Ned Wright’s Cosmology Tutorial – Classic online course from a UCLA cosmologist, featuring concise text, FAQ-style explanations, calculators, and up-to-date notes on observational results. 

Planck Mission – ESA – Official site for ESA’s cosmic-microwave-background satellite; includes plain-language summaries of the spacecraft, data releases, and what those measurements tell us about the age, composition, and geometry of the Universe. 

Khan Academy: Cosmology & Astronomy – Free, bite-sized video lessons (with quizzes) covering everything from the scale of the cosmos to dark energy, perfect for self-paced learning. 

Sloan Digital Sky Survey – Education & Outreach – Hands-on activities and lesson plans that let you explore real SDSS data on galaxy redshifts and large-scale structure—great for classrooms or independent projects. 

Particle Data Group “Review of Cosmological Parameters” (PDF) – The authoritative, annually updated overview of the latest precision measurements of H₀, Ωₘ, Ω_Λ, and more—written for scientists but freely available to all. 

HubbleSite – “Looking Deep” & Cosmology Features – Articles, videos, and interactive timelines showing how Hubble observations have reshaped our understanding of cosmic expansion, dark energy, and the early Universe. 

Universe Today – Cosmology Archive – Daily news and explainer articles that translate cutting-edge cosmology papers (galaxy evolution, dark-matter mapping, CMB studies) into plain English. 

Perimeter Institute – Cosmology – Outreach pages highlighting frontier theoretical work on inflation, dark energy, and quantum gravity, plus accessible blog posts and public-lecture videos. 

OpenStax “Astronomy 2e” – Cosmology Chapters – A free, college-level textbook with entire chapters (26 & 29) devoted to the expanding Universe, the cosmic distance ladder, dark energy, and the age of the cosmos.  

Data Science and Astronomy

DataSciencePrograms – The Role of Data Science in Astronomy – Article explaining how big-data techniques drive modern astrophysics. (Thanks to Susan and Amelia for suggesting this interesting link!)

History of Astronomy

Historical Astronomy Division (AAS) – A rich portal of digitized books, primary sources, and bibliographies maintained by the American Astronomical Society’s HAD. An excellent first stop for serious historical research. 

Chronology of Early Astronomy & Space Science – NASA GSFC – Scrollable timeline highlighting key milestones from ancient Babylonian records to 20th-century space telescopes. 

Interactive Timeline of Astronomy – The Schools’ Observatory – An engaging, clickable timeline that lets visitors “travel through time” and meet the people who built our understanding of the cosmos. 

Linda Hall Library Digital Collections – History of Astronomy – Free, high-resolution scans of rare celestial atlases, star catalogues, and classic texts, plus short curator essays that put each work in context. 

Adler Planetarium Online Exhibits – 25 Google Arts & Culture exhibits showcasing centuries of astronomical instruments, giant telescopes, and the people behind them. 

Society for the History of Astronomy – Digital Resources – Links to digitized observatory archives, historical star catalogues, and SHA presentations; ideal for deep dives into observational heritage. 

CK-12 “History of Astronomy” Lesson – Concise, student-friendly overview from ancient Greece to the Big Bang; good for readers who want a quick primer. 

Hubble History Timeline (NASA) – Text-based timeline following the space telescope’s journey from 1946 concept to decades of discovery, with links to imagery and science highlights. 

High-Energy Astronomy Chronology (HEASARC) – Year-by-year log of X-ray and gamma-ray astronomy milestones (1900–present) kept by NASA’s HEASARC. 

Observatories

Historic Observatories

Leviathan of Parsonstown (Birr Castle) – William Parsons’s 72-inch reflector (1845) was the world’s largest telescope for 72 years and first revealed spiral structure in “nebulae” such as M 51. 

Great Lick Refractor – Lick Observatory – Completed in 1888, the 36-inch refractor was then the biggest lens telescope and enabled seminal discoveries of galaxy rotation and the first asteroid moon. 

Yerkes Observatory (40-inch Refractor) – Dedicated 1897 in Wisconsin, still the largest refractor ever built and dubbed the “birthplace of modern astrophysics.” 

Hooker Telescope (100-inch) – Mt. Wilson – World’s largest (1917-48); Edwin Hubble used it to prove galaxies lie beyond the Milky Way and that the universe is expanding. 

Plaskett Telescope (72-inch) – Dominion Astrophysical Obs. – 1918 Canadian reflector that mapped the Milky Way’s rotation and mass distribution. 

Otto Struve Telescope (82-inch) – McDonald Obs. – 1939 instrument (2nd-largest then) pivotal for stellar spectroscopy and planet-search work. 

Hale Telescope (200-inch) – Palomar – Dedicated 1948; ruled optical astronomy until 1993, discovering quasars, brown dwarfs, and more. 

Lovell Telescope – Jodrell Bank – At 76 m, the largest steerable radio dish in 1957; tracked early space probes and found the first pulsar in a binary system. 

Arecibo Radio Telescope (305 m) – 1963–2016 record-holder for single-dish size, famous for radar-mapping asteroids, pulsar timing, and the Arecibo Message. 

Modern Observatories

W. M. Keck Observatory – Twin 10 m segmented-mirror telescopes on Maunakea; pioneers of adaptive optics and exoplanet imaging. 

ESO Very Large Telescope (VLT) – Four 8.2 m unit telescopes (plus 1.8 m auxiliaries) on Cerro Paranal that can combine as an interferometer for milli-arcsecond resolution. 

Extremely Large Telescope (ELT) – 39 m optical/IR giant under construction in Chile; will be the world’s largest eye on the sky by late 2020s. 

Giant Magellan Telescope (GMT) – Seven 8.4 m mirrors acting as one 25 m aperture; promises 10× Hubble’s resolution when it sees first light (~2030). 

Large Binocular Telescope (LBT) – Unique twin-mirror 2×8.4 m design on Mt. Graham, Arizona, achieving 22.8 m interferometric resolution for exoplanet and high-contrast imaging. 

Gemini Observatory (North & South) – Two 8.1 m telescopes in Hawai‘i and Chile offering full-sky coverage for optical/IR programs from supernovae to stellar birth. 

Subaru Telescope – 8.2 m Japanese telescope on Maunakea noted for ultra-wide-field imaging (Hyper Suprime-Cam) and surveys of dark matter & high-redshift galaxies. 

South African Large Telescope (SALT) – 11 m effective segmented mirror (largest in the Southern Hemisphere) conducting spectroscopy from exoplanets to distant quasars. 

LOFAR Radio Array – Europe-wide low-frequency radio array probing cosmic magnetism, transients, and the epoch of re-ionisation. 

FAST (500 m) Radio Telescope – China’s Five-hundred-meter Aperture Spherical Telescope, now the world’s largest single-dish radio instrument, excelling at pulsar and FRB discovery. 

Vera C. Rubin Observatory – 8.4 m wide-field survey telescope with a 3.2-gigapixel camera to carry out the decade-long Legacy Survey of Space and Time from 2025. 

Space Exploration & Missions

NASA Artemis Program – Gateway page for the return-to-the-Moon campaign, with mission timelines, technology overviews, and Moon-to-Mars plans. 

ESA Human & Robotic Exploration – European Space Agency portal for ISS activities, lunar initiatives, and future Mars missions, plus an interactive ISS tracker and astronaut news. 

JPL Mission Index – Up-to-date catalog of past, present, and planned NASA/JPL spacecraft with launch dates, objectives, images, and status reports. 

Planetary Society – Space Exploration Missions – Non-profit hub that explains why each mission matters, tracks active spacecraft, and offers ways to get involved in advocacy. 

Spaceflight Now – Launch Schedule – Continuously updated global manifest of upcoming launches, with vehicle/mission details and live-coverage links. 

RocketLaunch.live – Real-time launch calendar covering SpaceX, ULA, ESA, ISRO, Rocket Lab, and more, with filters, past-launch log, and mission alerts. 

NASA “Eyes on the Solar System” – Free 3-D web app that lets you fly alongside every NASA spacecraft—past, present, or future—and explore planets and moons in real time. 

NASA “Spot the Station” – Live map and alert service for tracking the International Space Station’s orbit and local sighting opportunities. 

NASASpaceflight.com – Independent news site offering in-depth reporting, insider analysis, and livestreams of launches, test campaigns, and commercial-space developments. 

SpaceX – Launches – Official mission page with upcoming and past Falcon-9, Falcon Heavy, Starship, and Dragon flights, including webcast replays and mission briefs. 

Blue Origin – New Shepard – Overview of Blue Origin’s reusable sub-orbital rocket system for science payloads and commercial crews, with flight history and vehicle specs. 

United Launch Alliance – ULA’s official site covering Atlas V, Delta IV Heavy, and Vulcan launches, mission archives, and vehicle fact sheets.  Stars, Star Formation & Stellar Evolution

NASA Science – Stars: Basics – Clear NASA primer on how stars form in cold molecular clouds, ignite fusion, evolve through distinct life-cycle stages, and seed the cosmos with heavy elements. 

ESA Science – The Lifecycle of Stars – Illustrated overview of where stars are born, what sets their masses, and how stellar deaths recycle material for new generations. 

OpenStax Astronomy 2e §21.2 “The H-R Diagram & Stellar Evolution” – Free college-level textbook chapter that traces evolutionary tracks across the Hertzsprung–Russell diagram for stars of different masses. 

Stellar Evolutionary Tracks Interactive – Penn State ASTRO 801 – Interactive HR diagram showing how a Sun-like star changes temperature and luminosity from protostar to main-sequence and beyond. 

“Birth of Stars” – Khan Academy Video – Five-minute lesson that explains gravitational collapse, protostars, and the onset of nuclear fusion in an accessible whiteboard style. 

ESA/Hubble – Formation of Stars – Image-rich explainer featuring spectacular Hubble mosaics of stellar nurseries such as the Orion Nebula and Carina’s dust pillars. 

Chandra X-ray Observatory – Stellar Evolution Infographic (PDF) – High-resolution flow-chart summarizing the life paths of low-, intermediate-, and high-mass stars from birth to endpoints like white dwarfs, neutron stars, and black holes. 

Stellar Structure & Evolution Simulator (UIUC) – Web app that lets you evolve stars of various masses on an HR diagram and visualize interior changes over time. 

AAVSO Manual for Visual Observing of Variable Stars (PDF) – Comprehensive 80-page guide to tracking brightness changes in variable stars, a key tool for studying stellar evolution in real time. 

NASA Image Feature – Formation of Stars – Short article highlighting Chandra, Spitzer, and ground-based imagery that reveals triggered star formation inside the Cepheus B molecular cloud. Quasars

Wikipedia – Quasar – Detailed reference on quasar properties, discovery, and cosmological relevance.

RASC – Visually Observing Quasars (PDF) – Guide to identifying and observing bright quasars with amateur gear.

Wikipedia – List of Quasars – Catalog of notable quasars with coordinates and finder info.

Looking for what’s visible tonight, ephemerides, and trackers? → Observing & Sky Events

Looking for object catalogs and databases? → Targets, Catalogs & Databases