http://www.polarlicht-vorhersage.de/#activity                                           Vorhersage Polarlicht

http://www.nist.gov/pml/data/handbook/index.cfm            handbook of basic atomic spectroscopic data

http://astrokramkiste.de/planeten-tabelle                                                    Planetendaten

http://www.avgoe.de/astro/beginner.html#Inhalt                                        Einfühung in die Astronomie

https://lp.uni-goettingen.de/get/text/7262                                      Astronomie-Studium und Grundbegriffe

http://barndoor-montierung.npage.de/                                                         Barndoor-Montierung

http://www.astronomie-tagebuch.de/seeing.php                                         Grundbegriffe werden erklärt

http://ned.ipac.caltech.edu/level5/Gray/frames.html                        A digital spectral classification atlas

http://ned.ipac.caltech.edu/level5/ASS_Atlas/frames.html                     An Atlas of Stellar Spectra          

http://iss.de.astroviewer.net/index.php                                                        aktuelle Position der ISS

http://users.erols.com/njastro/faas/pages/starcat.htm                                 Bright Star Spectral Types

http://www.atlasoftheuniverse.com/index.html                                          The atlas of the universe

http://www.atlasoftheuniverse.com/stars.html                                           The brightests stars

http://basebe.obspm.fr/basebe                                                         Be Star Spectra BeSS Datenbank v2.0

http://atlas.obs-hp.fr/elodie                                                           on-line database of high-resolution stellar spectra ELODIE

http://soho.nascom.nasa.gov/home.html                                                     SOHO Sonnensattelit

https://lp.uni-goettingen.de/get/text/6802                                 Einführung in Astronomie und Astrophysik

http://stahl-hd.mooo.com/otmar/specdb/                                                    VDS Datenbank

http://www.enchantedlearning.com/subjects/astronomy/stars/startypes.shtml     All about Astronomy

http://www.astr.ua.edu/keel/techniques/                                                     Astronomical Techniques

http://www.astro.virginia.edu/class/oconnell/astr511/                               Astronomical Techniques

http://www.star.bris.ac.uk/bjm/lectures/astech/                                          Astronomical Techniques

http://burro.cwru.edu/Academics/Astr306/index.html                               spectrographs and spectroscopy

http://astro.nineplanets.org/bigeyes.html                                     The World's Largest Optical Telescopes

http://astro.unl.edu/animationsLinks.html                                      Astronomy Simulations and Animations

http://users.erols.com/njastro/faas/pages/starcat.htm                                 Bright Star Spectra Index

http://www.astrogeo.va.it/astronom/spettri/spettrien.htm                          Schiaparelli Observatory

http://ned.ipac.caltech.edu/level5/catalogs.html                              IMAGES, CATALOGS & ATLASES

http://www.lafterhall.com/spectroscopy.html                                  Low Resolution Stellar Spectroscopy

http://www.swpc.noaa.gov/                                                                    Space Weather Prediction Center

http://www.astrosurf.com/aras/surveys/beactu/index.htm                     Longtime observations of Be stars

http://www.stsci.de/                                                                     Schnörringen Telescope Science Institut

http://www.aavso.org/vsots_betaper                                                           Beta Persei (Algol)

http://members.shaw.ca/rlmcnish/darksky/                                                Larry McNish's  Dark Sky Calculator  auch ALGOL