HAT-P-29

Star in the constellation Perseus

HAT-P-29 / Muspelheim
Observation data Epoch J2000 Equinox J2000
Constellation	Perseus
Right ascension	02^h 12^m 31.47875^s^[1]
Declination	+51° 46′ 43.5637″^[1]
Apparent magnitude (V)	11.83
Characteristics
Evolutionary stage	main-sequence star
Spectral type	G
Astrometry

Radial velocity (R_v)	−21.91±0.69^[1] km/s
Proper motion (μ)	RA: -9.972 mas/yr^[1] Dec.: 1.790 mas/yr^[1]
Parallax (π)	3.1358 ± 0.0201 mas^[1]
Distance	1,040 ± 7 ly (319 ± 2 pc)

Orbit^[2]
Primary	HAT-P-29
Companion	HAT-P-29 B
Semi-major axis (a)	3.290±0.002" (1041 AU)
Details^[3]

Mass	1.198^+0.065 _−0.063 `M`_☉
Radius	1.229^+0.080 _−0.073 `R`_☉
Luminosity	1.89^+0.3 _−0.25 `L`_☉
Surface gravity (log g)	4.337^+0.045 _−0.045 cgs
Temperature	6112±88 K
Metallicity [Fe/H]	0.128^+0.079 _−0.080 dex
Age	2.2±1.0^[4] Gyr

Other designations
Muspelheim, Gaia DR2 359058441314838528, TYC 3293-1539-1, GSC 03293-01539, 2MASS J02123147+5146435^[5]
Database references
SIMBAD	data

HAT-P-29, also known as Muspelheim since 2019 (as part of the IAU's NameExoWorlds project),^[6] is a star about 1,040 light-years (320 parsecs) away. It is a G-type main-sequence star. The star's age of 2.2±1.0 billion years is less than half that of the Sun.^[4] HAT-P-29 is slightly enriched in heavy elements, having 35% more iron than the Sun.

A very faint 19th-magnitude stellar companion was detected in 2016 at a projected separation of 3.290±0.002″,^[2] but Gaia DR2 astrometry suggests that this is an unrelated background object.^[7]

Planetary system

In 2011 a transiting hot Jupiter planet, HAT-P-29b, was detected on a mildly eccentric orbit.^[4] The planet was named "Surt" by Denmark in 2019.^[8] The planetary orbit is likely aligned with the equatorial plane of the star, with a misalignment equal to 26±16 degrees.^[9]

In 2018, a transit-timing variation survey indicated additional planets with masses exceeding approximately half of Earth are absent in the system.^[3]

The HAT-P-29 planetary system^[3]
Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b (Surt)	0.767^+0.046 _−0.045 M_J	0.0665±0.0012	5.723376±0.000021	0.073^+0.029 _−0.028	88.06^+0.78 _−0.59°	1.055^+0.079 _−0.072 R_J

References

^ ^a ^b ^c ^d ^e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
^ ^a ^b Ngo, Henry; Knutson, Heather A.; Hinkley, Sasha; Bryan, Marta; Crepp, Justin R.; Batygin, Konstantin; Crossfield, Ian; Hansen, Brad; Howard, Andrew W.; Johnson, John A.; Mawet, Dimitri; Morton, Timothy D.; Muirhead, Philip S.; Wang, Ji (2016), "FRIENDS OF HOT JUPITERS. IV. STELLAR COMPANIONS BEYOND 50 au MIGHT FACILITATE GIANT PLANET FORMATION, BUT MOST ARE UNLIKELY TO CAUSE KOZAI–LIDOV MIGRATION", The Astrophysical Journal, 827 (1): 8, arXiv:1606.07102, Bibcode:2016ApJ...827....8N, doi:10.3847/0004-637X/827/1/8, S2CID 41083068
^ ^a ^b ^c Wang, Songhu; Wang, Xian-Yu; Wang, Yong-Hao; Liu, Hui-Gen; Hinse, Tobias C.; Eastman, Jason; Bayliss, Daniel; Hori, Yasunori; Hu, Shao-Ming; Li, Kai; Liu, Jinzhong; Narita, Norio; Peng, Xiyan; Wittenmyer, R. A.; Wu, Zhen-Yu; Zhang, Hui; Zhang, Xiaojia; Zhao, Haibin; Zhou, Ji-Lin; Zhou, George; Zhou, Xu; Laughlin, Gregory (2018), "Transiting Exoplanet Monitoring Project (TEMP). I. Refined System Parameters and Transit Timing Variations of HAT-P-29b", The Astronomical Journal, 156 (4): 181, arXiv:1807.10107, Bibcode:2018AJ....156..181W, doi:10.3847/1538-3881/aadcfc, S2CID 119415237
^ ^a ^b ^c Buchhave, L. A.; Bakos, G. Á.; Hartman, J. D.; Torres, G.; Latham, D. W.; Andersen, J.; Kovács, G.; Noyes, R. W.; Shporer, A.; Esquerdo, G. A.; Fischer, D. A.; Johnson, J. A.; Marcy, G. W.; Howard, A. W.; Béky, B.; Sasselov, D. D.; Fűrész, G.; Quinn, S. N.; Stefanik, R. P.; Szklenár, T.; Berlind, P.; Calkins, M. L.; Lázár, J.; Papp, I.; Sári, P. (2011), "HAT-P-28b AND HAT-P-29b: TWO SUB-JUPITER MASS TRANSITING PLANETS", The Astrophysical Journal, 733 (2): 116, arXiv:1103.1813, Bibcode:2011ApJ...733..116B, doi:10.1088/0004-637X/733/2/116, S2CID 119293967
^ "HAT-P-29". SIMBAD. Centre de données astronomiques de Strasbourg.
^ IAU100 NameExoWorlds APPROVED NAMES
^ Mugrauer, M.; et al. (2019). "Search for stellar companions of exoplanet host stars by exploring the second ESA-Gaia data release". Monthly Notices of the Royal Astronomical Society. 490 (4): 5088. Bibcode:2019MNRAS.490.5088M. doi:10.1093/mnras/stz2673.
^ Denmark names new planet after Norse fire giant Surt
^ Mancini, L.; et al. (2022), "The GAPS Programme at TNG", Astronomy & Astrophysics, 664: A162, arXiv:2205.10549, doi:10.1051/0004-6361/202243742, S2CID 248986121

Constellation of Perseus

Stars

Bayer	α (Mirfak) β (Algol) γ δ ε ζ η (Miram) θ ι κ (Misam) λ μ ν ξ (Menkib) ο (Atik) π ρ σ τ φ ψ ω b
Flamsteed	1 2 3 4 (g) 5 7 8 9 (i) 10 11 12 14 16 17 20 21 24 29 30 31 32 (l) 34 36 40 (o) 42 (n) 43 (A) 48 (c) 49 50 52 (f) 53 (d) 54 55 56 57 (m) 58 (e) 59 1 Aur
Variable	S T U V X Z RS RT RV RW RY ST SU SV TZ UV UX UY VX XX XY XZ YZ AB AG AR AS AW AX BM DM DY FO GK IK IP IQ IU IW IX IZ KP KS KT KW LX V351 V356 V357 V361 V376 V380 V386 V392 V396 V400 V423 V432 V440 V459 V461 V471 V472 V473 V480 V490 V492 V505 V509 V518 V520 (61 And) V521 V545 V551 V572 V573 V575 V576 V621 V718 V1024
HR	470 526 529 538 540 621 641 787 792 810 820 831 842 846 849 864 865 876 885 886 890 894 918 (k) 920 923 930 949 950 956 964 966 969 973 975 979 986 991 1001 1019 1034 1037 1041 1047 1051 1056 1059 1074 1097 1113 1127 1130 1133 1141 1160 1164 1176 1191 1197 1198 1207 1215 1226 1234 1286 1301 1330 1333 1337 1344 1371 1390 1419 1424 1482 1489 1493 1500 1514
HD	13519 14433 14434 16691 16760 17092 17245 17605 21684 22781 23301 23596 25329 26702 29587
Other	BD+31 643 BD+48 740 G 38-29 G 95-57 GD 61 HAT-P-15 (Berehynia) HAT-P-29 (Muspelheim) IRAS 04296+3429 L1448-IRS2E LkHα 101 LRLL 54361 NGC 1333 13 NGC 1333 IRAS 2A NGC 1333 IRAS 4A NGC 1333 IRAS 4B NGC 1624-2 PSR B0355+54 PSR J0357+3205 WR 4

Exoplanets	WASP-11b/HAT-P-10b

Star
clusters

NGC	869 (h) 884 (χ) 957 1039 1220 1285 1342 1444 1513 1528 1545 1624
Other	Alpha Persei Cluster IC 348 Trumpler 2

Nebulae

NGC	650 (Little Dumbbell Nebula) 1333 1491 1499 (California Nebula) 1579
Other	Barnard 203 Wreath Nebula

Galaxies

NGC	1003 1023 1058 1077 1160 1161 1167 1169 1250 1259 1260 1264 1265 1267 1268 1270 1271 1272 1273 1274 1275 1277 1278 1279 1281 1282 1283 1293 1294 1334
Other	UGC 2885 (Godzilla galaxy) 4C +37.11