 Artistic illustration of the AE Aquarii system | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 20h 40m 09.16206s [1] |
| Declination | −00° 52′ 15.0618″ [1] |
| Apparent magnitude (V) | 11.6 [2] |
| Characteristics | |
| Spectral type | White dwarf + K4–5 V [3] |
| B−V color index | −1.2 [2] |
| Variable type | DQ Her |
| Astrometry | |
| Radial velocity (Rv) | −53 [4] km/s |
| Proper motion (μ) | RA: +73.95 [1] mas/yr Dec.: +12.40 [1] mas/yr |
| Parallax (π) | 11.61±2.72 mas [1] |
| Distance | approx. 280 ly (approx. 90 pc) |
| Absolute magnitude (MV) | ~6.6 [5] |
| Orbit [6] | |
| Period (P) | 9.88 hours |
| Semi-major axis (a) | 2.34 ± 0.02 R☉ |
| Inclination (i) | 70 ± 3° |
| Details | |
| A | |
| Mass | 0.63 ± 0.05 [6] M☉ |
| Radius | 0.01 [7] R☉ |
| Rotation | 33.08 sec [8] |
| B | |
| Mass | 0.37 ± 0.04 [6] M☉ |
| Radius | 0.79 [6] R☉ |
| Other designations | |
| 2E 2037.5-0102, GCRV 71273, 1RXS J204009.4-005216, AN 342.1931, 2E 4404, GSC 05177-00636, SBC7 826, 1AXG J204011-0052, RJHA 119, CSI-01-20376, CDS 1178, HIP 101991, 1E 2037.5-0102, 1ES 2037-01.0, 2MASS J20400915-0052151, AAVSO 2035-01. [2] | |
| Database references | |
| SIMBAD | data |
AE Aquarii is a cataclysmic variable binary star of the DQ Herculis type. Based upon parallax measurements, the system is located at a distance of about 280 light-years (86 parsecs ) from the Earth. [1] Because of its unique properties, this system has been subject to a number of scientific studies. [3] The white dwarf in the AE Aquarii system is the first star of its type known to give off pulsar-like pulsations that are powered by its rotation and particle acceleration. [9] [10] [11]
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Arno Arthur Wachmann discovered that the star was variable after examining four photographic plates taken from 1923 through 1930. He classified the star as a mira variable based on that sparse data set. Wachmann published the discovery in 1931, naming the star 342.1931 Aquarii. [13] In 1938, Ernst Zinner classified the star, which by then had received the variable star designation AE Aquarii, as a cataclysmic variable, based upon a much larger data set. [14]
The AE Aquarii system consists of an ordinary star in a close orbit around a magnetic white dwarf; the pair orbit each other with a period of 9.88 hours. The white dwarf primary has 63% of the Sun's mass but a radius of only about 1% of the Sun. As of 2009, it has the shortest known spin period of any white dwarf, completing a full revolution every 33.08 seconds. This spin is decreasing at a rate of 1.78 ns per year, which is unusually high. [3] The secondary star has a stellar classification of K4-5 V, making it a main sequence star that is generating energy at its core through the thermonuclear fusion of hydrogen. It has about 37% of the Sun's mass but 79% of the Sun's radius.
This system displays flare activity that has been observed across multiple bands of the electromagnetic spectrum, including X-rays. Mass is being lost from the secondary star, most of which is being flung out of the system by the rapidly spinning magnetic primary. The X-ray luminosity is likely being caused by the accretion of mass onto the white dwarf, which is occurring at an estimated rate of about 7.3 × 1010 kg per second. [3]
