Delta Muscae
Encyclopedia
Delta Muscae often catalogued as HD 112985, is a spectroscopic binary star system and the closest to the Earth
in the southern hemisphere
constellation
of Musca (the Fly
) at a distance of approximately 27.8 parsec
s (91.0 light years). The main star is classified as a giant star
with an orange tint. It is one of the stars given a Bayer designation
by astronomer Johann Bayer
. It was recorded in Bayer's 1603 publication Uranometria
. In addition it is one of the main stars used in the visual formation of the Musca constellation.
for the Hipparcos Star Catalogue, Delta Muscae exhibits a parallax
of 35.91 milliarcseconds. With this data, it can be calculated that Delta Muscae is situated at a distance of 27.8 parsec
s, or 91.0 light years, from the sun.
Even though Delta Muscae is the closest star to Earth in the Musca constellation, nearly 3800 stars are closer in proximity to the Earth as stated by the Gliese Catalogue of Nearby Stars
, which includes stars within twenty-five parsecs of the Sun.
Delta Muscae is a star of the third magnitude
(or 3.61(v) to be exact) when viewed from the Earth
, and is visible to the naked eye
in regions that lack dense light pollution
.
of K2III. The K2 portion of this designation specifies that Delta Muscae A is a class K2 star, meaning the light it emits is orange in color. The main star burns at a temperature cooler than our own sun
(Sol), which is a G2 star. K2 stars are on the smaller end of the Harvard spectral classification list, solely being larger than Class-M dwarves. The second part of the classification, III, specifies that Delta Muscae is a giant star
which has yet to reach the main sequence
of star life like our sun.
These spectral designations are for the main star in the Delta Muscae system. The system itself has been identified as a spectroscopic binary star system; this means that Delta Muscae was identified as a binary system
by analyzing the Doppler Effect
from the emitted light of the star. There is no available data concerning Delta Muscae A's companion.
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
in the southern hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Musca (the Fly
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
) at a distance of approximately 27.8 parsec
Parsec
The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....
s (91.0 light years). The main star is classified as a giant star
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
with an orange tint. It is one of the stars given a Bayer designation
Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name...
by astronomer Johann Bayer
Johann Bayer
Johann Bayer was a German lawyer and uranographer . He was born in Rain, Bavaria, in 1572. He began his study of philosophy in Ingolstadt in 1592, and moved later to Augsburg to begin work as a lawyer. He grew interested in astronomy during his time in Augsburg...
. It was recorded in Bayer's 1603 publication Uranometria
Uranometria
Uranometria is the short title of a star atlas produced by Johann Bayer.It was published in Augsburg, Germany, in 1603 by Christophorus Mangus under the full title Uranometria : omnium asterismorum continens schemata, nova methodo delineata, aereis laminis expressa. This translates to...
. In addition it is one of the main stars used in the visual formation of the Musca constellation.
Distance and visibility
Based on research done by the European Space AgencyEuropean Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
for the Hipparcos Star Catalogue, Delta Muscae exhibits a parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...
of 35.91 milliarcseconds. With this data, it can be calculated that Delta Muscae is situated at a distance of 27.8 parsec
Parsec
The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....
s, or 91.0 light years, from the sun.
Even though Delta Muscae is the closest star to Earth in the Musca constellation, nearly 3800 stars are closer in proximity to the Earth as stated by the Gliese Catalogue of Nearby Stars
Gliese Catalogue of Nearby Stars
The Gliese Catalogue of Nearby Stars is a frequently referenced, modern star catalogue of stars located within 25 parsecs of the Earth.-First edition and supplements:...
, which includes stars within twenty-five parsecs of the Sun.
Delta Muscae is a star of the third magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
(or 3.61(v) to be exact) when viewed from the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
, and is visible to the naked eye
Naked eye
The naked eye is a figure of speech referring to human visual perception unaided by a magnifying or light-collecting optical device, such as a telescope or microscope. Vision corrected to normal acuity using corrective lenses is considered "naked"...
in regions that lack dense light pollution
Light pollution
Light pollution, also known as photopollution or luminous pollution, is excessive or obtrusive artificial light.The International Dark-Sky Association defines light pollution as:...
.
Stellar and system characteristics
Delta Muscae has a listed spectral typeStellar classification
In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are most prominent in the light, giving an objective measure...
of K2III. The K2 portion of this designation specifies that Delta Muscae A is a class K2 star, meaning the light it emits is orange in color. The main star burns at a temperature cooler than our own sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
(Sol), which is a G2 star. K2 stars are on the smaller end of the Harvard spectral classification list, solely being larger than Class-M dwarves. The second part of the classification, III, specifies that Delta Muscae is a giant star
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
which has yet to reach the main sequence
Main sequence
The main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell...
of star life like our sun.
These spectral designations are for the main star in the Delta Muscae system. The system itself has been identified as a spectroscopic binary star system; this means that Delta Muscae was identified as a binary system
Binary system
Binary system may refer to:* Binary numeral system, the base-2 internal "machine language" of computers* Binary opposition, a bipolar distinction in philosophy, structuralism and critical theory...
by analyzing the Doppler Effect
Doppler effect
The Doppler effect , named after Austrian physicist Christian Doppler who proposed it in 1842 in Prague, is the change in frequency of a wave for an observer moving relative to the source of the wave. It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from...
from the emitted light of the star. There is no available data concerning Delta Muscae A's companion.
See also
- List of stars in Musca
- Table of stars with Bayer designationsTable of stars with Bayer designationsThis table lists those stars/objects which have Greek-letter Bayer designations.Only those stars which have individual articles are shown in the table. The name given is that of the article if it does not reflect the Bayer designation...
- Musca constellationMuscaMusca is one of the minor southern constellations. The constellation was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman and it first appeared on a 35-cm diameter celestial globe published in 1597 in Amsterdam by...