HD 61005, also known as HIP 36948, is a young star located in the southern constellation Puppis, the poop deck. It has an

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

of 8.22, making it readily visible in binoculars, but not to the

naked eye Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal ...

. The object is located relatively close at a distance of 119 light years based on

Gaia DR3 The ''Gaia'' catalogues are star catalogues created using the results obtained by '' Gaia'' space telescope. The catalogues are released in stages that will contain increasing amounts of information; the early releases also miss some stars, espec ...

parallax measurements but is receding with a heliocentric radial velocity of .

Characteristics

HD 61005 has a stellar classification of G8 Vk, indicating that it is a yellow dwarf with interstellar absorption features in its spectrum. However, it is younger than the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

at an age of 30 million years. Other studies place it an older age, ranging from 135 million years to 2

billion years A billion years or giga-annum (109 years) is a unit of time on the petasecond scale, more precisely equal to seconds (or simply 1,000,000,000 years). It is sometimes abbreviated Gy, Ga ("giga-annum"), Byr and variants. The abbreviations Gya or ...

. Nevertheless, the star retains a

protoplanetary disk A protoplanetary disk is a rotating circumstellar disc of dense gas and dust surrounding a young newly formed star, a T Tauri star, or Herbig Ae/Be star. The protoplanetary disk may also be considered an accretion disk for the star itself, be ...

- the accumulation of the gas-dust matter, forming a planetary system. HD 61005 is located in the

Local Bubble The Local Bubble, or Local Cavity, is a relative cavity in the interstellar medium (ISM) of the Orion Arm in the Milky Way. It contains the closest of celestial neighbours and among others, the Local Interstellar Cloud (which contains the Sol ...

, a region with a low concentration of dust clouds. It is suspected to be a member of the Argus association. It has 96% the mass of the Sun and 81% of its

solar radius Solar radius is a unit of distance used to express the size of stars in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3: :1\,R_ = 6.957\ ...

. It radiates 61% of the

luminosity of the Sun The solar luminosity (), is a unit of radiant flux ( power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun. One nominal ...

from its photosphere at an effective temperature of , giving it a yellow hue. HD 61005 has a solar metallicity — what astronomers dub

chemical element A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...

s heavier than

helium Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. ...

; it spins modestly with a

projected rotational velocity Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bulg ...

of .

Protoplanetary disk

In 2007,

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

Dean C. Hines and colleagues announced the discovery of a

around HD 61005. The disk has an unusual shape, which may be due to the influence of the dense regions of the interstellar medium. The researchers also suggest that the passage through these areas can affect the atmosphere of planets that form. The disc diameter and morphologically resembles a

butterfly Butterflies are insects in the macrolepidopteran clade Rhopalocera from the order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The group comprise ...

shape, so it was appropriate for the informal name. Analysis of the data did not confirm the presence of

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

s in the system. File:Star HD 61005.jpg, Annoted

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

photo of HD 61005

References

{{DEFAULTSORT:HD 61005 G-type main-sequence stars Puppis 061005 36948 BD+31 4778 Circumstellar disks