All articles starting with H
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Helium flash
The helium flash, or core helium flash, is the thermonuclear runaway that ignites helium burning in the degenerate core of a low-mass red giant star, fusing helium into carbon at about 10^8 K.
Helium hydride ion
The helium hydride ion (HeH+), or protonated helium, is a positively charged molecular ion of helium and a proton that formed the Universe's first molecular bond.
Helium ion beam milling
Helium ion beam milling is a nanofabrication technique in which a finely focused helium ion beam sputters atoms from a surface, cutting features as small as 4 to 5 nm.
Helium liquefaction
Helium liquefaction is the process of cooling helium gas below its boiling point of 4.2 K into liquid helium, used to cool superconducting magnets and medical imaging equipment.
Helium-3
Helium-3 (He-3) is a stable, non-radioactive helium isotope with two protons and one neutron, extraordinarily rare on Earth and prized for cryogenics, neutron detection, and fusion research.
Helium-4
Helium-4 (⁴He) is the stable isotope of helium whose nucleus is the alpha particle, making up almost all naturally occurring helium and about 25% of the universe's baryon mass.
Helium-cadmium laser
The helium-cadmium laser (HeCd laser) is a continuous-wave gas laser using excited helium to vaporize cadmium, emitting ultraviolet and blue-violet light for microscopy and lithography.
Helium-core white dwarf
A helium-core white dwarf is a low-mass white dwarf, below about 0.48 solar masses, made of helium, formed when a binary companion strips a red giant's envelope.
Helium-ion microscopy
Helium-ion microscopy (HIM) is an imaging technique that scans a focused beam of helium ions to form sub-nanometer surface images. It is highly surface-sensitive, offering better contrast and a larger depth of field than an SEM.
Helium–neon laser
The helium–neon laser, or HeNe laser, is a continuously operating gas laser first demonstrated at Bell Labs in December 1960, the first laser to produce a continuous beam.
Helix
A helix is a smooth space curve that winds around a fixed axis at constant distance while advancing at a constant rate, like a screw thread.
Helix (AI model)
Helix is a vision-language-action model developed by Figure AI and announced in February 2025 to control its humanoid robots end-to-end from camera pixels and natural-language commands.
Helix (band)
Helix is a Canadian hard rock/heavy metal band formed in 1974 in Kitchener, Ontario, as the Helix Field Band, best known for the 1984 hit "Rock You" from Walkin' the Razor's Edge; vocalist Brian Vollmer is the sole constant member across 14 studio albums.
Helix (TV series)
Helix is an American sci-fi horror TV series created by Cameron Porsandeh, airing on Syfy January 10, 2014 to April 10, 2015 in two seasons, about CDC scientists fighting a viral outbreak at an Arctic research facility; executive produced by Ronald D. Moore, Steven Maeda, and Lynda Obst.
Helix Nebula
The Helix Nebula (NGC 7293), nicknamed the Eye of God, is a planetary nebula in Aquarius about 700 light-years away, cast off by a dying Sun-like star.
Helix pomatia
Helix pomatia, the Roman snail or Burgundy snail, is a large European helicid land snail (shell 3.8–5.0 cm) eaten as escargot de Bourgogne; IUCN Least Concern, stable, on EU Habitats Directive Annex IV.
Helix Studios
Helix Studios: American gay pornographic film studio founded 2002 by Keith Miller in Fort Lauderdale, Florida, now based in Las Vegas; subscription model, twink-focused, narrative films on Amazon Prime Video; distinct from Helix Interactive game studio.
Helixon (Huashen Zhiyao)
Helixon (华深智药) is a Beijing-based AI-driven antibody drug discovery company founded in 2021 and incubated by Tsinghua University's Institute for AI Industry Research, operating internationally as Earendil Labs.
Helkavirsiä
Helkavirsiä ("Songs of Helka") is a two-part collection of poems by the Finnish poet Eino Leino, written in the Kalevala meter; the series appeared in 1903 and 1916.
Hell
Hell is the afterlife realm where the dead suffer punishment or separation, a place of torment in Christian and Muslim teaching and a temporary realm in Buddhism.
Hell and Back (film)
Hell & Back (2015) is an R-rated adult stop-motion animated comedy by ShadowMachine, directed by Tom Gianas and Ross Shuman, about friends rescuing Curt from Hell; it grossed $157,768 and scored 35% on Rotten Tomatoes.
Hell at Night
Hell at Night is a country-rap song by BigXthaPlug and Ella Langley, released in 2025. It became a top-ten hit on Billboard's Hot Country Songs chart.
Hell Awaits
Hell Awaits, Slayer's second studio album (Metal Blade, 1985, seven tracks, 37:12), the slow, demonic record that shaped extreme metal before Reign in Blood, later remastered for its 40th anniversary.
Hell Bent (Doctor Who)
Hell Bent is the 2015 Doctor Who Series 9 finale (episode 12), written by Steven Moffat and directed by Rachel Talalay, in which the Doctor returns to Gallifrey after 4.5 billion years in the confession dial and saves Clara via a reversed memory wipe.
Hell Creek Formation
The Hell Creek Formation is a rock unit in Montana, Wyoming, and the Dakotas famous for its dinosaur fossils, including Tyrannosaurus rex, and preserving the Cretaceous–Paleogene extinction boundary.
Hell Drivers
Hell Drivers is a 1957 British trucking crime drama directed by blacklisted American Cy Endfield, starring Stanley Baker, Patrick McGoohan, Herbert Lom, Peggy Cummins, and a young Sean Connery, shot in VistaVision.
Hell Fest
Hell Fest is a 2018 American slasher film directed by Gregory Plotkin, in which a masked killer stalks friends at a Halloween horror theme park.
Hell Followed with Us
Hell Followed with Us is Andrew Joseph White's 2022 YA post-apocalyptic horror debut (Peachtree Teen) about trans boy Benji, infected with the bioweapon Seraph by the cult that raised him, joining the Acheson LGBTQ+ Center; a New York Times bestseller, Morris Award finalist, and planned animated film.
Hell Freezes Over
Hell Freezes Over (1994) is the Eagles' reunion album and MTV concert film, titled from Don Henley's 1980 quote. Four new studio songs plus live unplugged-style tracks; No. 1 Billboard debut, 9× Platinum US, launched a multi-year reunion tour.
Hell Gate
Hell Gate (Dutch Hellegat) is the treacherous tidal strait of the East River between Wards Island and Astoria, Queens, New York City, where currents reach 4 knots; its rocks were blasted away at Hallett's Point in 1876 and Flood Rock on October 10, 1885. Not the Hell Gate news outlet or bridge alone.