Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cepheus |
Right ascension | 22h 02m 04.57263s [2] |
Declination | +58° 00′ 01.3098″ [2] |
Apparent magnitude (V) | 5.6 [3] |
Characteristics | |
Spectral type | O 9III (primary) + ON 9.7V (secondary) [4] |
Variable type | Rotating ellipsoidal variable [5] |
Astrometry | |
Proper motion (μ) | RA: −3.096±0.061 [2] mas/yr Dec.: −2.611±0.054 [2] mas/yr |
Parallax (π) | 0.9070 ± 0.0525 mas [2] |
Distance | 3,600 ± 200 ly (1,100 ± 60 pc) |
Orbit [4] | |
Period (P) | 3.070507 d |
Eccentricity (e) | 0.0 |
Inclination (i) | 49±2.4° |
Semi-amplitude (K1) (primary) | 88.72±1.02 km/s |
Semi-amplitude (K2) (secondary) | 224.48±2.58 km/s |
Details | |
Primary | |
Mass | 16.0 [4] M☉ |
Radius | 11.7+3.3 −2.7 [4] R☉ |
Luminosity | 79,000 [3] L☉ |
Surface gravity (log g) | 3.71±0.02 [3] cgs |
Temperature | 32,000±1,000 [4] K |
Secondary | |
Mass | 6.5 [4] M☉ |
Radius | 9.4+2.6 −2.2 [4] R☉ |
Luminosity | 45,000 [3] L☉ |
Surface gravity (log g) | 3.48±0.02 [3] cgs |
Temperature | 28,000±1,000 [4] K |
Other designations | |
Database references | |
SIMBAD | data |
LZ Cephei, also known by its Flamsteed designation 14 Cephei, is a star about 3,600 light years from the Earth, in the constellation Cepheus. Its apparent magnitude is 5.6, making it faintly visible to the naked eye of an observer far from city lights. [3] The star is a rotating ellipsoidal variable whose brightness, as measured by the Hipparcos satellite, varies between magnitude 5.52 and 5.61. [5]
LZ Cephei was discovered to be a binary star by William Edmund Harper in 1931. [7] The orbital elements were first calculated by Robert Methven Petrie in 1962. [7] It was discovered to be a variable star in 1972 by N. Kameswara Rao, using the Lick Observatory's 24 inch telescope. [8] The star was given the variable star designation LZ Cephei in 1973. [9] It was classified as an ellipsoidal variable by Hill et al. in 1976. [10]
A 2011 study of LZ Cephei concluded that the existing data are best explained if the system is a semi-detached binary with either the primary or secondary star nearly filling its Roche lobe. The secondary star, now less massive than the primary, was originally the more massive star, and matter has been transferred from the secondary to the primary. [4]
Gamma Cephei is a binary star system approximately 45 light-years away in the constellation of Cepheus. The primary is a stellar class K1 orange giant or subgiant star; it has a red dwarf companion. An exoplanet has been confirmed to be orbiting the primary.
Mu Cephei, also known as Herschel's Garnet Star, Erakis, or HD 206936, is a red supergiant or hypergiant star in the constellation Cepheus. It appears garnet red and is located at the edge of the IC 1396 nebula. Since 1943, the spectrum of this star has served as a spectral standard by which other stars are classified.
Delta Cephei is the Bayer designation for a quadruple star system located approximately 887 light-years away in the northern constellation of Cepheus, the King. At this distance, the visual magnitude of the star is diminished by 0.23 as a result of extinction caused by gas and dust along the line of sight. It is the prototype of the Cepheid variable stars that undergo periodic changes in luminosity.
9 Aurigae is a star system in Auriga (constellation). It has an apparent magnitude of about 5, making it visible to the naked eye in many suburban skies. Parallax estimates made by the Hipparcos spacecraft put it at about 85.7 light-years from the solar system.
2 Lacertae is a binary star in the constellation of Lacerta. With an apparent magnitude of about 4.5, it is faintly visible to the naked eye. Its parallax, measured by the Hipparcos spacecraft, is 5.88 milliarcseconds, corresponding to a distance of about 550 light years. It is projected against the Lacertae OB1 stellar association to the northeast of the main concentration of stars, but it is likely to be a foreground object.
Eta Lyrae, a name Latinized from η Lyrae, is a likely binary star system in the northern constellation of Lyra. It has the traditional name Aladfar and is faintly visible to the naked eye with an apparent visual magnitude of 4.43. The system is located at a distance of approximately 1,390 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −8 km/s.
VV Cephei, also known as HD 208816, is an eclipsing binary star system located in the constellation Cepheus, approximately 5,000 light years from Earth. It is both a B[e] star and shell star.
V354 Cephei is a red supergiant star located within the Milky Way. It is an irregular variable located over 8,900 light-years away from the Sun. It has an estimated radius of 685 solar radii. If it were placed in the center of the Solar System, it would extend to between the orbits of Mars and Jupiter.
Zeta Cephei is a star in the constellation of Cepheus. Zeta Cephei marks the left shoulder of Cepheus, the King of Joppa (Ethiopia). It is one of the fundamental stars of the MK spectral sequence, defined as type K1.5 Ib.
Theta2 Crucis, Latinized from θ2 Crucis, is a spectroscopic binary star in the constellation Crux. This pair of stars complete an orbit every 3.4280 days and they have a low orbital eccentricity that is close to 0.0. Theta2 Crucis is located at about 690 light-years from the Sun.
Theta Cephei, Latinized from θ Cephei, is a stellar class A7, fourth-magnitude star in the constellation Cepheus. This displays at a metallic-line Am star. It is a white-hued, single-lined spectroscopic binary system, located about 127 light-years from Earth. The pair have an orbital period of 2.5 years; the eccentricity was long thought to be low, at 0.03, but recent calculations have put it at a much higher 0.377. They are separated by 4.16 AU. The companion star is calculated to be about 400 times fainter than the primary. It is completely invisible in the spectrum, but is estimated to be a K7 main sequence star.
HD 106515 is a binary star in the constellation of Virgo.
HD 37756 is a binary star system in the equatorial constellation of Orion, positioned less than a degree to the north of the bright star Alnitak. It has a blue-white hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.95. The system is located at a distance of approximately 900 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +26 km/s. It is a member of the OB1b subgroup of the Orion OB1 association.
QZ Puppis is a class B2.5V star in the constellation Puppis. Its apparent magnitude is 4.5 and it is approximately 650 light years away based on parallax.
16 Lacertae is a triple star system in the northern constellation of Lacerta, located about 1,580 light years from the Sun. It has the variable star designation EN Lacertae; 16 Lacertae is the Flamsteed designation. This system is visible to the naked eye as a faint blue-white hued star with a maximum apparent visual magnitude of +5.587. It is moving closer to the Earth with a heliocentric radial velocity of –12 km/s.
Psi2 Orionis a binary star system in the equatorial constellation of Orion. It has an apparent visual magnitude of 4.6, indicating that it is visible to the naked eye. Based upon an annual parallax shift of 2.87 mass, it is roughly 1,100 light years distant from the Sun.
DH Cephei is a variable binary star system in the northern circumpolar constellation of Cepheus, positioned about two degrees to the east of the star system Delta Cephei. With an apparent visual magnitude of 8.61, it is too faint to be visible without a telescope. Based on parallax measurements, this system is located at a distance of approximately 9.6 kilolight-years from the Sun. At present it is moving closer to the Earth with a radial velocity of −33 km/s.
SY Equulei, also known as HD 203664, is a single variable star located in the equatorial constellation Equuleus. It has an average apparent magnitude of about 8.5, varying by a few hundredths of a magnitude, making it readily visible in binoculars and small telescopes, but not to the naked eye. The star is relatively far away at a distance of 8,000 light years and is receding with a heliocentric radial velocity of 48 km/s. At that distance, SY Equulei is dimmed by 0.19 magnitudes due to interstellar dust.
RS Sagittarii is an eclipsing binary star system in the southern constellation of Sagittarius, abbreviated RS Sgr. It is a double-lined spectroscopic binary with an orbital period of 2.416 days, indicating that the components are too close to each other to be individually resolved. The system has a combined apparent visual magnitude of 6.01, which is bright enough to be faintly visible to the naked eye. During the primary eclipse the brightness drops to magnitude 6.97, while the secondary eclipse is of magnitude 6.28. The distance to this system is approximately 1,420 light years based on parallax measurements.
HD 224355, also known as V1022 Cassiopeiae, HR 9059 and Boss 6148, is an eclipsing binary star in the constellation Cassiopeia. It ranges in apparent magnitude from 5.57 to 5.68, which means it is faintly visible to the naked eye for an observer located well away from city lights. It is one of the few binaries known to be an astrometric, spectroscopic and eclipsing binary, a combination that allows the parameters of the stellar system to be calculated with high accuracy. HD 224355 lies 16′ west of the 5th-magnitude σ Cassiopeiae.