WISPIT 2

WISPIT 2 (also called TYC 5709-354-1) is a pre-main-sequence star in the constellation Aquila. It is part of the Scorpius-Centaurus OB association, likely belonging to the subgroup Theia 53. The star has a directly imaged circumstellar disk with multiple rings and one directly imaged protoplanet inside one of the gaps.^[2] This protoplanet was also detected in H-alpha, showing it is surrounded by a circumplanetary disk.^[3]

WISPIT 2

The disk around WISPIT 2 with VLT SPHERE. The protoplanet WISPIT 2b is inside the gap of the disk on the lower right Credit: ESO/R. F. van Capelleveen et al.
Observation data Epoch J2000      Equinox J2000
Constellation	Aquila
Right ascension	19h 23m 17.03s
Declination	−07° 40′ 55.07″
Apparent magnitude (V)	11.60±0.12[1]
Characteristics
Evolutionary stage	pre-main-sequence star
Astrometry
Radial velocity (Rv)	−16.23±14.58[2] km/s
Proper motion (μ)	RA: 6.308±0.024 mas/yr[2] Dec.: −27.138±0.018 mas/yr[2]
Parallax (π)	7.4649±0.0214 mas[2]
Distance	437 ± 1 ly (134.0 ± 0.4 pc)
Details[2]
Mass	1.08+0.06 −0.17 M☉
Radius	1.418±0.004 R☉
Luminosity (bolometric)	0.699±0.021 L☉
Surface gravity (log g)	4.00±0.25 cgs
Temperature	4400±50 K
Rotation	4.7004 days
Age	5.1+2.4 −1.3 Myr
Other designations
TYC 5709-354-1, IRAS 19205-0746, IRAS F19205-0746, Gaia DR2 4207586980945067648
Database references
SIMBAD	data

The circumstellar disk

The disk was classified as transitional, meaning it has an inner cavity.^[3] The disk has 4 rings and one prominent gap at 68 astronomical units (AU). The outermost ring is located at 316 AU and the disk was detected out to a distance of 2.8 arcseconds (380 AU) from the star. The inclination of the disk is around 44° to 46°.^[2]

Planetary system

Observations with VLT SPHERE,^[2] Magellan MagAO-X and LBT/LMIRcam revealed one planet located inside gap 3.^[3] The protoplanet was confirmed to move with the star and shows orbital motion in images from October 2023 to April 2025. The planet has a mass of around 5 M_J and is responsible for clearing a gap inside the disk.^[2] The protoplanet is also detected in H-alpha, showing that it is accreting material from a circumplanetary disk. This makes WISPIT 2b similar to the PDS 70 planets, 2MJ1612b and possibly LkCa 15b.^[3]

Annotated thermal-infrared image of the WISPIT 2 protoplanetary system seen with LBTI/LMIRcam. Credit: Laird Close & Gabriel Weible (University of Arizona)

One additional inner candidate planet was detected, but CC1 could also be a dust clump and needs further observations to be confirmed as a planet.^[3]

The WISPIT 2 planetary system^[2][3]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (years)	Eccentricity	Inclination	Radius
CC1 (unconfirmed)	9±4 MJ	15	—	—	—	—
Ring 3	38.44±0.09 AU				44.95±0.39°	—
b	5.3±1.0 MJ	57.5	—	—	—	1.6±0.2 RJ
Gap 3	69.0±0.6 AU				44.2±0.8°	—
Ring 2	96.7±0.6 AU				41.8±0.6°	—
Ring 1	163.6±2.9 AU				45.4±1.1°	—
Ring 0	316.4±4.5 AU				43.6±1.5°	—

See also

• List of directly imaged exoplanets