Mauna Kea in the context of "University of California, Santa Cruz"

The Mauna Kea Observatories (MKO) are a group of independent astronomical research facilities and large telescope observatories that are located at the summit of Mauna Kea on Hawaiʻi, United States. The facilities are located in a 525-acre (212 ha) special land use zone known as the "Astronomy Precinct", which is located within the 11,228-acre (4,544 ha) Mauna Kea Science Reserve. The Astronomy Precinct was established in 1967 and is located on land protected by the Historical Preservation Act for its significance to Hawaiian culture. The presence and continued construction of telescopes is highly controversial due to Mauna Kea's centrality in native Hawaiian religion and culture, as well as for a variety of environmental reasons.

The location is nearly ideal because of its dark skies from lack of light pollution, good astronomical seeing due to low atmospheric turbulence, low humidity, high elevation of 4,207 m (13,802 ft), position above most of the water vapor in the atmosphere, clean air, low cloud cover and low latitude location.

The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have 10 m (33 ft) aperture primary mirrors, and, when completed in 1993 (Keck I) and 1996 (Keck II), they were the largest optical reflecting telescopes in the world. They have been the third and fourth largest since 2006.

Mauna Loa (/ˌmɔːnə ˈloʊ.ə, ˌmaʊnə -/, Hawaiian: [ˈmɐwnə ˈlowə]; lit. 'Long Mountain') is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean. Mauna Loa is Earth's largest active volcano by both mass and volume. It was historically considered to be the largest volcano on Earth until the submarine mountain Tamu Massif was discovered to be larger. Mauna Loa is a shield volcano with relatively gentle slopes, and a volume estimated at 18,000 cubic miles (75,000 km), although its peak is about 125 feet (38 m) lower than that of its neighbor, Mauna Kea. Lava eruptions from Mauna Loa are silica-poor and very fluid, and tend to be non-explosive.

Mauna Loa has likely been erupting for at least 700,000 years, and may have emerged above sea level about 400,000 years ago. Some dated rocks are 470,000 years old. The volcano's magma comes from the Hawaii hotspot, which has been responsible for the creation of the Hawaiian Island chain over tens of millions of years. The slow drift of the Pacific Plate will eventually carry Mauna Loa away from the hotspot within 500,000 to one million years from now, at which point it will become extinct.

2023 KQ₁₄, informally nicknamed Ammonite, is a trans-Neptunian object (TNO) orbiting the Sun on an extremely wide elliptical orbit. It was discovered by the Subaru Telescope atop Mauna Kea on 16 May 2023, as part of an internationally led astronomical survey known as the "Formation of the Outer Solar System: an Icy Legacy" (FOSSIL) survey. 2023 KQ₁₄ is unusual because the direction of its orbital apsides is not aligned with those of previously known TNOs with high-perihelion elliptical orbits (sometimes known as sednoids), which challenges the hypothesis that an unseen distant planet ("Planet Nine") could be aligning their orbits. 2023 KQ₁₄ likely has a diameter between 220 and 380 km (140 and 240 mi).

This is a list of the tallest mountains in the Solar System. This list includes peaks on all celestial bodies where significant mountains have been detected. For some celestial bodies, different peaks are given across different types of measurement. The solar system's tallest mountain is possibly the Olympus Mons on Mars with an altitude of 21.9 to 26 km. The central peak of Rheasilvia on the asteroid Vesta is also a candidate to be the tallest, with an estimated at up to between 19 and 22 km from peak to base.

Hilo /ˈhiːloʊ/ (Hawaiian pronunciation: [ˈhilo]) is the largest settlement in and the county seat of Hawaiʻi County, Hawaii, United States, which encompasses the Island of Hawaiʻi, and is a census-designated place (CDP). The population was 44,186 according to the 2020 census. It is the fourth-largest settlement in the state of Hawaiʻi, the largest settlement in the state outside of Oahu, and the largest settlement in the state outside of the Greater Honolulu Area.

Hilo is in the District of South Hilo. The city overlooks Hilo Bay and has views of two shield volcanoes – Mauna Loa, an active volcano, and Mauna Kea, a dormant volcano. The Hilo bayfront has been destroyed by tsunamis twice. The majority of human settlement in Hilo stretches from Hilo Bay to Waiākea-Uka, on the flanks of the volcanoes.

The evolution of Hawaiian volcanoes occurs in several stages of growth and decline. The fifteen volcanoes that make up the eight principal islands of Hawaii are the youngest in a chain of more than 129 volcanoes that stretch 5,800 kilometers (3,600 mi) across the North Pacific Ocean, called the Hawaiian–Emperor seamount chain. Hawaiʻi's volcanoes rise an average of 4,600 meters (15,000 ft) to reach sea level from their base. The largest, Mauna Loa, is 4,169 meters (13,678 ft) high. As shield volcanoes, they are built by accumulated lava flows, growing a few meters or feet at a time to form a broad and gently sloping shape.

Hawaiian islands undergo a systematic pattern of submarine and subaerial growth that is followed by erosion. An island's stage of development reflects its distance from the Hawaii hotspot.

The James Clerk Maxwell Telescope (JCMT) is a submillimetre-wavelength radio telescope at Mauna Kea Observatory in Hawaii, US. The telescope is near the summit of Mauna Kea at 13,425 feet (4,092 m). Its primary mirror is 15 metres (16.4 yards) across: it is the largest single-dish telescope that operates in submillimetre wavelengths of the electromagnetic spectrum (far-infrared to microwave). Scientists use it to study the Solar System, interstellar dust and gas, and distant galaxies.

The JCMT started operations in 1987, and was funded until February 2015 by a partnership between the United Kingdom and Canada, and the Netherlands. It was operated by the Joint Astronomy Centre and was named in honour of mathematical physicist James Clerk Maxwell. In March 2015 the operation of the JCMT was taken over by the East Asian Observatory. Funding is provided by the National Astronomical Observatory of China, National Astronomical Observatory of Japan, Korea Astronomy and Space Science Institute, and the Academia Sinica Institute of Astronomy and Astrophysics of Taiwan.

The Tharsis Montes (/ˈθɑːrsɪs ˈmɒntiːz/) are three large shield volcanoes in the Tharsis region of the planet Mars. From north to south, the volcanoes are Ascraeus Mons, Pavonis Mons and Arsia Mons. Mons (plural montes) is the Latin word for mountain; it is a descriptor term used in astrogeology for mountainous features in the Solar System.

The three Tharsis Montes volcanoes are enormous by terrestrial standards, ranging in diameter from 375 km (233 mi) (Pavonis Mons) to 475 km (295 mi) (Arsia Mons). Ascraeus Mons is the tallest with a summit elevation of over 18 km (59,000 ft), or 15 km (49,000 ft) base-to-peak. For comparison, the tallest volcano on Earth, Mauna Kea in Hawaii, is about 120 km (75 mi) across and stands 9 km (30,000 ft) above the ocean floor.

Argyroxiphium sandwicense, the Hawaiʻi silversword, or hinahina is a species of silversword. It is endemic to Hawaii. The two subspecies are separated by geography. Both subspecies are rare, threatened and federally protected.

• Haleakala silversword (A. sandwicense subsp. macrocephalum) is found on the mountain Haleakalā on the island of Maui at elevations above 2,100 m (6,900 ft). It is a federally listed threatened species.
• Mauna Kea silversword (A. sandwicense subsp. sandwicense) is found on the mountain Mauna Kea on the Hawaii Island at elevations above 2,600 m (8,500 ft). It is a federally listed endangered species. As few as 40 individuals are left.