HD 36112
HD 36112, also known as MWC 758, is a young Herbig Ae star located in the constellation Taurus, surrounded by irregular rings of cosmic dust. The system is about 3.5 million years old. The disk has a cavity at 50 astronomical units and two spiral arms at 30-75 au that are seen in near-infrared scattered light, but only one spiral arm is seen in ALMA images.
HD 36112 and the surrounding dusty disk. The rings in the disk were measured as being elliptical in shape rather than being perfectly circular. Credit: ESO/R. Dong et al.; ALMA (ESO/NAOJ/NRAO) | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 05h 30m 27.52856s |
| Declination | +25° 19′ 57.0763″ |
| Characteristics | |
| Spectral type | A8Ve |
| Astrometry | |
| Proper motion (μ) | RA: 3.685(33) mas/yr Dec.: −26.373(22) mas/yr |
| Parallax (π) | 6.4157 ± 0.0314 mas |
| Distance | 508 ± 2 ly (155.9 ± 0.8 pc) |
| Other designations | |
| Database references | |
| SIMBAD | data |
The inner cavity was shown to be elliptical and not perfectly circular. This is not a projection effect but represents the shape of the cavity, with an eccentricity e ≈ 0.1 after the deprojection of the disk.
A 2018 study detected a possible exoplanet at a distance of about 20 au, designated MWC 758 b, and the observations with ALMA have also shown evidence of an unseen planet at 100 au. A study in 2019 came to the conclusion that a 1.5 MJ planet at 35 au and a 5 MJ planet at 140 au could explain the features seen with ALMA and the VLA.
In another 2019 study, a possible exoplanet or disk feature was detected with the Large Binocular Telescope, referred to as MWC 758 CC1 (Companion Candidate 1), with a non-detection of MWC 758 b. However, another study in 2021 failed to detect either of the point sources found in earlier studies. A 2023 study found further evidence for MWC 758 CC1, now designated MWC 758 c, orbiting at a distance of approximately 100 au.