![<span class="mw-page-title-main">Proplyd</span> Dust ring surrounding large stars thousands of solar radii wide](https://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Orion_Nebula_with_proplyd_highlights_%28captured_by_the_Hubble_Space_Telescope%29.jpg/320px-Orion_Nebula_with_proplyd_highlights_%28captured_by_the_Hubble_Space_Telescope%29.jpg)
A proplyd, short for ionized protoplanetary disk, is an externally illuminated photoevaporating protoplanetary disk around a young star. Nearly 180 proplyds have been discovered in the Orion Nebula. Images of proplyds in other star-forming regions are rare, while Orion is the only region with a large known sample due to its relative proximity to Earth.
![<span class="mw-page-title-main">Rogue planet</span> Planets not gravitationally bound to a star](https://upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Artist%27s_impression_of_the_free-floating_planet_CFBDSIR_J214947.2-040308.9.ogv/320px--Artist%27s_impression_of_the_free-floating_planet_CFBDSIR_J214947.2-040308.9.ogv.jpg)
A rogue planet, also termed a free-floating planet (FFP) or an isolated planetary-mass object (iPMO), is an interstellar object of planetary mass which is not gravitationally bound to any star or brown dwarf.
Photoevaporation is the process where energetic radiation ionises gas and causes it to disperse away from the ionising source. The term is typically used in an astrophysical context where ultraviolet radiation from hot stars acts on clouds of material such as molecular clouds, protoplanetary disks, or planetary atmospheres.
![<span class="mw-page-title-main">HD 107146</span> Star in the constellation Coma Berenices](https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/HD_107146_falsecolour.jpg/320px-HD_107146_falsecolour.jpg)
HD 107146 is a star in the constellation Coma Berenices that is located about 90 light-years (28 pc) from Earth. The apparent magnitude of 7.028 makes this star too faint to be seen with the unaided eye.
![<span class="mw-page-title-main">Rho Coronae Borealis</span> Star in the constellation Corona Borealis](https://upload.wikimedia.org/wikipedia/commons/thumb/4/41/Corona_Borealis_constellation_map.svg/320px-Corona_Borealis_constellation_map.svg.png)
Rho Coronae Borealis is a yellow dwarf star 57.1 light-years away in the constellation of Corona Borealis. The star is thought to be similar to the Sun with nearly the same mass, radius, and luminosity. It is orbited by four known exoplanets.
HD 210277 is a single star in the equatorial constellation of Aquarius. It has an apparent visual magnitude of 6.54, which makes it a challenge to view with the naked eye, but it is easily visible in binoculars. The star is located at a distance of 69.6 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −20.9 km/s.
![<span class="mw-page-title-main">Flame Nebula</span> Emission nebula in the constellation Orion](https://upload.wikimedia.org/wikipedia/commons/thumb/3/36/NASA-FlameNebula-NGC2024-20140507.jpg/320px-NASA-FlameNebula-NGC2024-20140507.jpg)
The Flame Nebula, designated as NGC 2024 and Sh2-277, is an emission nebula in the constellation Orion. It is about 1350 light-years away. At that distance, the Flame Nebula lies within the Orion B cloud of the larger Orion Molecular Cloud Complex.
![<span class="mw-page-title-main">NGC 2244</span> Open cluster within the Rosette nebula, in the constellation Monoceros](https://upload.wikimedia.org/wikipedia/commons/thumb/4/44/Rosette_Nebula_in_Monoceros.jpg/320px-Rosette_Nebula_in_Monoceros.jpg)
NGC 2244 is an open cluster in the Rosette Nebula, which is located in the constellation Monoceros. This cluster has several O-type stars, super hot stars that generate large amounts of radiation and stellar wind.
HD 98800, also catalogued as TV Crateris, is a quadruple star system in the constellation of Crater. Parallax measurements made by the Hipparcos spacecraft put it at a distance of about 150 light-years away. The system is located within the TW Hydrae association (TWA), and has received the designation TWA 4.
HD 210277 b is an extrasolar planet orbiting the star HD 210277. It was discovered in September 1998 by the California and Carnegie Planet Search team using the highly successful radial velocity method. The planet is at least 24% more massive than Jupiter. The mean distance of the planet from the star is slightly more than Earth's distance from the Sun. However, the orbit is very eccentric, so at periastron this distance is almost halved, and at apastron it is as distant as Mars is from the Sun.
HD 23514, is a star in the Pleiades. It is a main-sequence star of class F6, and has been seen to have hot dust particles orbiting around it. These materials, otherwise known as planetesimals which orbit within a circumstellar disc, are evidence of possible planetary formation. The debris disk shows evidence of being rich in silica.
![<span class="mw-page-title-main">HD 61005</span> Star in the constellation Puppis](https://upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Star_HD_61005_with_circumstellar_disk.jpg/320px-Star_HD_61005_with_circumstellar_disk.jpg)
HD 61005, also known as HIP 36948 and The Moth, is a young star located in the southern constellation Puppis, the poop deck. It has an apparent magnitude of 8.22, making it readily visible in binoculars, but not to the naked eye. The object is located relatively close at a distance of 119 light years based on Gaia DR3 parallax measurements but is receding with a heliocentric radial velocity of 22.6 km/s.
HD 219623 is a solitary star in the northern circumpolar constellation of Cassiopeia. HD 219623 is its Henry Draper Catalogue designation. It has an apparent visual magnitude of 5.59, which lies in the brightness range that is visible to the naked eye. According to the Bortle scale, it can be observed from dark suburban skies. Parallax measurements place it at an estimated distance of around 67.2 light years. It has a relatively high proper motion, advancing 262 mas per year across the celestial sphere.
![<span class="mw-page-title-main">NGC 4298</span> Galaxy in the constellation Coma Berenices](https://upload.wikimedia.org/wikipedia/commons/thumb/8/86/NGC_4298_cropped.jpg/320px-NGC_4298_cropped.jpg)
NGC 4298 is a flocculent spiral galaxy located about 53 million light-years away in the constellation Coma Berenices. The galaxy was discovered by astronomer William Herschel on April 8, 1784 and is a member of the Virgo Cluster.
![<span class="mw-page-title-main">NGC 4302</span> Galaxy in the constellation Coma Berenices](https://upload.wikimedia.org/wikipedia/commons/thumb/e/e6/SDSS_NGC_4302.jpg/320px-SDSS_NGC_4302.jpg)
NGC 4302 is an edge-on spiral galaxy located about 55 million light-years away in the constellation Coma Berenices. It was discovered by astronomer William Herschel on April 8, 1784 and is a member of the Virgo Cluster.
A Peter Pan disk is a circumstellar disk around a star or brown dwarf that appears to have retained enough gas to form a gas giant planet for much longer than the typically assumed gas dispersal timescale of approximately 5 million years. Several examples of such disks have been observed to orbit stars with spectral types of M or later. The presence of gas around these disks has generally been inferred from the total amount of radiation emitted from the disk at infrared wavelengths, and/or spectroscopic signatures of hydrogen accreting onto the star. To fit one specific definition of a Peter Pan disk, the source needs to have an infrared "color" of , an age of >20 Myr and spectroscopic evidence of accretion.
![<span class="mw-page-title-main">Tucana-Horologium association</span> Large stellar association](https://upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Galaxymap.com%2C_map_100_parsecs_%282022%29.png/320px-Galaxymap.com%2C_map_100_parsecs_%282022%29.png)
The Tucana-Horologium association (Tuc-Hor), or Tucana Horologium moving group, is a stellar association with an age of 45 ± 4 Myr and it is one of the largest stellar associations within 100 parsecs. The association has a similar size to the Beta Pictoris moving group (BPMG) and contains, like BPMG, more than 12 stars with spectral type B, A and F. The association is named after two southern constellations, the constellation Tucana and the constellation Horologium.
HD 46588 is a star in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.44, allowing it to be faintly seen with the naked eye. The object is relatively close at a distance of only 59 light years but is receding with a heliocentric radial velocity of 15 km/s.
HD 194012 is a star in the equatorial constellation Delphinus. It has an apparent magnitude of 6.15, making it visible to the naked eye under ideal conditions. The star is relatively close at a distance of only 85 light years but is receding with a heliocentric radial velocity of 4.5 km/s.