H
| Name | Established | Location |
| HALCA (defunct) | 1997–2005 | Elliptical earth-centered orbit |
| Haleakala Observatory | Maui, Hawaii, USA | |
| Halley Observatory | 1987 | Heesch, Netherlands |
| Hamburg Observatory | 1803 | Hamburg, Germany |
| Hat Creek Radio Observatory | 1950s | Shasta County, California, USA |
| Hard Labor Creek Observatory | Atlanta, Georgia, USA | |
| Hartung–Boothroyd Observatory | 1974 | Ithaca, New York, USA |
| Hartebeesthoek Radio Astronomy Observatory | 1961 | Gauteng, South Africa |
| Harvard College Observatory | 1839 | Cambridge, Massachusetts, USA |
| Harvard–Smithsonian Center for Astrophysics | 1973 | Cambridge, Massachusetts, USA |
| Haute-Provence Observatory | 1937 | Alpes-de-Haute-Provence, France |
| Haystack Observatory | 1964 | Westford, Massachusetts, USA |
| Hector J Robinson Observatory | 1964 | Lincoln Park, Michigan, USA |
| Helsinki University Observatory | 1834 | Helsinki/Kirkkonummi, Finland |
| Herrett Observatory | 2004 | Twin Falls, Idaho, USA |
| Herschel Space Observatory | 2009 | Earth–Sun L2 point |
| Hidden Valley Observatory | 1960s | Rapid City, South Dakota, USA |
| High Energy Stereoscopic System | 2002 | Khomas Region, Namibia |
| Hinode | 2006 | Low Earth orbit |
| Hirsch Observatory | 1942 | Troy, New York, USA |
| Hobbs Observatory | 1974 | Fall Creek, Wisconsin, USA |
| Hoher List Observatory | 1954 | Daun, Germany |
| Holcomb Observatory and Planetarium | 1954 | Indianapolis, Indiana, USA |
| Hong Kong Observatory | 1883 | Tsim Sha Tsui, Kowloon, Hong Kong |
| Hopkins Observatory | 1838 | Williamstown, Massachusetts, USA |
| Howell Observatory | Starkville, Mississippi, USA | |
| Hradec Králové Observatory | 1961 | Hradec Králové, Czech Republic |
| Huairou Solar Observing Station | Beijing, China | |
| Hubble Space Telescope | 1990 | Low Earth orbit |
| Hyde Memorial Observatory | 1977 | Lincoln, Nebraska, USA |
Read more about this topic: List Of Astronomical Observatories