Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Carina |
Right ascension | 10h 36m 15.428s [1] |
Declination | −59° 35′ 53.67″ [1] |
Apparent magnitude (V) | 5.8 – 19.9 [2] |
Characteristics | |
Variable type | Classical Nova [3] |
Astrometry | |
Proper motion (μ) | RA: -7.511 [1] mas/yr Dec.: 3.267 [1] mas/yr |
Parallax (π) | 0.3140 ± 0.3113 mas [1] |
Distance | 3300+2900 −1500 [4] pc |
Details [5] | |
White dwarf | |
Mass | 0.71+0.23 −0.19 [5] M☉ |
Radius | 0.03 R☉ |
Luminosity | 0.28 L☉ |
Temperature | 15,000 K |
Donor | |
Mass | 0.23 - 0.43 M☉ |
Radius | ~0.24 R☉ |
Luminosity | 0.03 L☉ |
Temperature | 4,951 K |
Other designations | |
Database references | |
SIMBAD | data |
V906 Carinae, also known as Nova Carinae 2018, was a nova in the Milky Way galaxy which appeared in the constellation Carina, near the 5th magnitude star HD 92063. It was discovered on images taken on 20.32 March 2018 by the All Sky Automated Survey for SuperNovae (ASAS-SN] telescope at the Cerro Tololo Inter-American Observatory. The ASAS-SN group assigned the name ASASSN-18fv to the object. The discovery image was saturated, allowing researchers to determine only that the object was brighter than apparent magnitude 10. An earlier image obtained by ASAS-SN on 26.32 March 2018 showed the nova was a magnitude ~10.4 object at that time, and the object was not detected on ASAS-SN images taken on 15.34 March 2018 and earlier. [6]
V906 Carinae was featured in the Astronomy Picture of the Day on 25 March 2018. [7]
Pre-discovery images of V906 Carinae were matched to a star of Gaia magnitude 20.1. On 21 March 2018, it had brightened to a Gaia magnitude 7.80 (visual magnitude 7.45), [8] and to magnitude 6.62 later the same day. [9] Also on 21 March 2018, long exposure spectrographic measurements of ASASSN-18fv, specifically in the 3800Å to 7300Å range, were captured using CCD imaging. Detailed analysis of the spectral data confirmed that ASASSN-18fv exhibited characteristics of a classical nova. [10]
All novae are binary stars, with a "donor" star orbiting a white dwarf. The two stars are so close to each other that material is transferred from the donor to the white dwarf. In the case of V906 Carinae, data from the Transiting Exoplanet Survey Satellite suggests that the binary system has an orbital period of either 1.641 hours or twice that value. [4] The mass of the white dwarf has been estimated to be 0.71 M☉, and the donor is believed to be a dwarf of spectral type K or M and a mass of 0.23 - 0.43 M☉. [5]
One of the stars monitored by the Bright-star Target Explorer (BRITE) nanosatellite constellation was HD 92063. V906 Carinae was close enough to that star to be serendipitously observed by BRITE. [5] In the BRITE data, the nova's maximum brightness occurred on 14 April 2018. BRITE provided a measurement of the nova's brightness every 1.6 hours, allowing the fluctuations near the peak of the outburst to be seen clearly. There were eight post-maximum flares with amplitudes of a few tenths of a magnitude each of which lasted 1 to 3 days. These flares in the visible portion of the EM spectrum occurred at the same times that γ-ray flares were seen by Fermi-LAT. Because the γ-ray flares are believed to arise from shocks in the ejected material, their correlation with visible flares suggests that most of the visible light from the nova may be produced in shocks, rather than the nuclear burning on the white dwarf's surface. [4]
NGC 4725 is an intermediate barred spiral galaxy with a prominent ring structure, located in the northern constellation of Coma Berenices near the north galactic pole. It was discovered by German-born British astronomer William Herschel on April 6, 1785. The galaxy lies at a distance of approximately 40 megalight-years from the Milky Way. NGC 4725 is the brightest member of the Coma I Group of the Coma-Sculptor Cloud, although it is relatively isolated from the other members of this group. This galaxy is strongly disturbed and is interacting with neighboring spiral galaxy NGC 4747, with its spiral arms showing indications of warping. The pair have an angular separation of 24′, which corresponds to a projected linear separation of 370 kly. A tidal plume extends from NGC 4747 toward NGC 4725.
NGC 1566, sometimes known as the Spanish Dancer, is an intermediate spiral galaxy in the constellation Dorado, positioned about 3.5° to the south of the star Gamma Doradus. It was discovered on May 28, 1826 by Scottish astronomer James Dunlop. At 10th magnitude, it requires a telescope to view. The distance to this galaxy remains elusive, with measurements ranging from 6 Mpc up to 21 Mpc.
NGC 4666 is a spiral galaxy in the equatorial constellation of Virgo, located at a distance of approximately 55 megalight-years from the Milky Way. It was discovered by the German-born astronomer William Herschel on February 22, 1784. It is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. John L. E. Dreyer described it as "bright, very large, much extended 45°±, pretty suddenly brighter middle". It is a member of an interacting system with NGC 4668 and a dwarf galaxy, and belongs to a small group that also includes NGC 4632.
KT Eridani was a bright nova in the constellation Eridanus that produced an outburst in 2009. It was the first classical nova ever detected in that constellation. The nova was discovered at 12:52 UT on 25 November 2009 by K. Itagaki at Yamagata, Japan with a 21 cm patrol telescope. At the time of its discovery, it was a magnitude 8.1 object. The discovery occurred after the nova's peak brightness, but the All Sky Automated Survey system had detected the nova on three earlier occasions, allowing a more complete light curve to be produced. The peak magnitude, 5.4, was seen at 15:10 UT on 14 November 2009, at which time it would have been visible to the naked eye.
V1369 Centauri, also known as Nova Centauri 2013, was a bright nova in the constellation Centaurus that occurred in 2013. It was discovered on December 2, 2013 by amateur astronomer John Seach in Australia with a magnitude of 5.5. On December 14, 2013 it peaked at about magnitude 3.3, making it the brightest nova so far of this millennium.
HV 2112 is a cool luminous variable star in the Small Magellanic Cloud. Until 2018, it was considered to be the most likely candidate for a Thorne–Żytkow object, but it is now thought to be an asymptotic giant branch star.
ASASSN-15lh is an extremely luminous astronomical transient event discovered by the All Sky Automated Survey for SuperNovae (ASAS-SN), with the appearance of a superluminous supernova event. It was first detected on June 14, 2015, located within a faint galaxy in the southern constellation Indus, and was the most luminous supernova-like object ever observed. At its peak, ASASSN-15lh was 570 billion times brighter than the Sun, and 20 times brighter than the combined light emitted by the Milky Way Galaxy. The emitted energy was exceeded by PS1-10adi.
The All Sky Automated Survey for SuperNovae (ASAS-SN) is an automated program to search for new supernovae and other astronomical transients, headed by astronomers from the Ohio State University, including Christopher Kochanek and Krzysztof Stanek. It has 20 robotic telescopes in both the northern and southern hemispheres. It can survey the entire sky approximately once every day.
V5856 Sagittarii, also known as Nova Sagittarii 2016 Number 4, was the 4th and brightest nova that occurred in the constellation Sagittarius during 2016. It was discovered by the All Sky Automated Survey for SuperNovae on 25.02 October 2016, at which time it had an apparent visual magnitude of 13.7. It was independently discovered by Yukio Sakurai of Mito, Ibaraki, Japan on 26.38 October 2016, by which time it had reached magnitude 10.4. It reached its peak brightness of magnitude 5.4, making it visible to the naked eye, on 8 November 2016. The nova occurred within a region of the sky monitored by the OGLE microlensing experiment, and that group reported that no star brighter than magnitude 22 was seen at the nova's position prior to its eruption.
V407 Lupi, also known as Nova Lupi 2016, was a bright nova in the constellation Lupus discovered by All Sky Automated Survey for SuperNovae (ASAS-SN) on 24.00 September 2016. At the time of its discovery, it had an apparent visual magnitude of 9.1. The ASAS-SN team reported that no object at the nova's location brighter than magnitude 17.5 was seen on images taken four days earlier. Wildly incorrect coordinates were published in the announcement telegram, but corrected in a subsequent telegram. It reached a peak brightness of magnitude 5.6, faintly visible to the naked eye, on 25 September 2016.
NGC 5643 is an intermediate spiral galaxy in the constellation Lupus. Based on the tip of the red-giant branch distance indicator, it is located at a distance of about 40 million light-years. NGC 5643 has an active galactic nucleus and is a type II Seyfert galaxy.
NGC 4424 is a spiral galaxy located in the equatorial constellation of Virgo. It was discovered February 27, 1865 by German astronomer Heinrich Louis d'Arrest. This galaxy is located at a distance of 13.5 million light years and is receding with a heliocentric radial velocity of 442 km/s. It has a morphological class of SB(s)a, which normally indicates a spiral galaxy with a barred structure (SB), no inner ring feature (s), and tightly-wound spiral arms (a). The galactic plane is inclined at an angle of 62° to the line of sight from the Earth. It is a likely member of the Virgo Cluster of galaxies.
V392 Persei, also known as Nova Persei 2018, is a bright nova in the constellation Perseus discovered on April 29, 2018. It was previously known as a dwarf nova.
ASASSN-19bt was a tidal disruption event (TDE) discovered by the All Sky Automated Survey for SuperNovae (ASAS-SN) project, with early-time, detailed observations by the TESS satellite. It was first detected on January 21, 2019, and reached peak brightness on March 4. The black hole which caused the TDE is in the 16th magnitude galaxy 2MASX J07001137-6602251 in the constellation Volans at a redshift of 0.0262, around 375 million light years away.
YZ Reticuli, also known as Nova Reticuli 2020 was a naked eye nova in the constellation Reticulum discovered on July 15, 2020. Previously it was known as a VY Sculptoris type object with the designation MGAB-V207.
FM Circini, also known as Nova Circini 2018, was a nova which appeared in the constellation Circinus in 2018. It was discovered by John Search of Chatsworth Island, New South Wales, Australia on 19.708 January 2018, using a DSLR with a 50 mm F/1.2 lens. At the time of its discovery, it had an apparent visual magnitude of 9.1. It was confirmed to be a nova spectroscopically on 21 January 2018. FM Circini reached a peak brightness of magnitude 5.8 on 22 March 2018, making it visible to the naked eye.
Nova Herculis 2021, also known V1674 Herculis, was a nova in the constellation Hercules. It reached a peak brightness of magnitude 6.0, making it visible to the naked eye under ideal observing conditions. It was discovered on June 12, 2021, by Seiji Ueda of Kushiro Japan, just hours before it obtained peak brightness. The discovery images were taken with a Canon EOS 6D digital camera with a 200 mm lens, when the nova was at magnitude 8.4. Subsequent analysis of ASAS-SN data showed the star had a magnitude of 16.62 8.4 hours before it was discovered. Of the galactic novae for which detailed light curves are available, Nova Herculis 2021 had the fastest decline from peak brightness ever seen. This nova has been detected throughout the electromagnetic spectrum, from radio to gamma rays.
Nova Cassiopeiae 2021, also known V1405 Cassiopeiae, was a nova in the constellation Cassiopeia. It reached a peak brightness of magnitude 5.449 on May 9, 2021, making it visible to the naked eye. It was discovered by Japanese amateur astronomer Yuji Nakamura of Kameyama, Japan, at 10:10 UT on March 18, 2021. The nova was first seen by Nakamura in four 15 second CCD exposures with a 135mm F/4 lens, when it was at magnitude 9.3. Nothing was seen brighter than magnitude 13.0 with the same equipment in exposures taken at 10:12 UT on March 14, 2021. For the first seven months after discovery, the nova's brightness stayed at a rough plateau, fading and rebrightening at least eight times; it is considered a very slow nova. After the seven month long series of peaks, Nova Cassiopeiae began a linear decline in brightness. This nova has been detected throughout the electromagnetic spectrum, from radio to gamma rays.