PDS 70

PDS 70

The protoplanetary disk of PDS 70 with new planet PDS 70b (right)
Observation data
Epoch J2000      Equinox J2000
Constellation Centaurus
Right ascension 14h 08m 10.15451s[1]
Declination −41° 23′ 52.5766″[1]
Apparent magnitude (V) 12[2]
Characteristics
Spectral type K5[3]
U−B color index 0.71[4]
B−V color index 1.06[4]
Astrometry
Radial velocity (Rv)3.13[1] km/s
Proper motion (μ) RA: -29.661[1] mas/yr
Dec.: -23.823[1] mas/yr
Parallax (π)8.8159 ± 0.0405[1] mas
Distance370 ± 2 ly
(113.4 ± 0.5 pc)
Details
Mass0.82[2] M☉
Radius1.39[4] R☉
Temperature4406[4] K
Rotation~50 days[3]
Rotational velocity (v sin i)~10[3] km/s
Other designations
V1032 Cen, 2MASS J14081015-4123525, IRAS 14050−4109
Database references
SIMBADdata

PDS 70 (V1032 Centauri) is a low-mass T Tauri star in the constellation Centaurus. Located approximately 370 light-years from Earth, it has a mass of 0.82 M☉,[2] and is approximately 10 million years old.[5] The star has a protoplanetary disk containing a nascent exoplanet, named PDS 70b, which has been imaged, the first confirmed image of a newborn planet.[6][7][8]

Protoplanetary disk

The protoplanetary disk around PDS 70 was first hypothesized in 1992[9] and confirmed in 2006 along with a jet-like structure.[2] The disk has a radius of approximately 140 au. In 2012 a large gap (~65 au) in the disk was discovered, which was thought to be caused by planetary formation.[3][5]

The gap was later found to have multiple regions: large dust grains were absent out to 80 au, while small dust grains were only absent out to the previously-observed 65 au. There is an asymmetry in the overall shape of the gap; these factors indicate that there are likely multiple planets affecting the shape of the gap and the dust distribution.[10]

In results published in 2018, a planet in the disk, named PDS 70b, was imaged by the VLT.[7][8] With a mass estimated to be a few times greater than Jupiter, the planet is thought to have a temperature of around 1000 °C and an atmosphere with clouds; its orbit has an approximate radius of 3 billion kilometres (20 au), taking around 120 years for a revolution. Modelling predicts that the planet has acquired its own accretion disk.[6][11]

References

  1. 1 2 3 4 5 6 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051.
  2. 1 2 3 4 Riaud, P.; Mawet, D.; Absil, O.; Boccaletti, A.; Baudoz, P.; Herwats, E.; Surdej, J. (2006). "Coronagraphic imaging of three weak-line T Tauri stars: evidence of planetary formation around PDS 70". Astronomy & Astrophysics. 458 (1): 317–325. Bibcode:2006A&A...458..317R. doi:10.1051/0004-6361:20065232.
  3. 1 2 3 4 Hashimoto, J.; et al. (2012). "Polarimetric Imaging of Large Cavity Structures in the Pre-Transitional Protoplanetary Disk Around PDS 70: Observations of the Disk". The Astrophysical Journal. 758 (1): L19. arXiv:1208.2075. Bibcode:2012ApJ...758L..19H. doi:10.1088/2041-8205/758/1/L19.
  4. 1 2 3 4 Gregorio-Hetem, J.; Hetem, A. (2002). "Classification of a selected sample of weak T Tauri stars". Monthly Notices of the Royal Astronomical Society. 336 (1): 197–206. Bibcode:2002MNRAS.336..197G. doi:10.1046/j.1365-8711.2002.05716.x.
  5. 1 2 "Giant Gap PDS 70's Protoplanetary Disk May Indicate Multiple Planets". SciTechDaily. 12 November 2012. Retrieved 30 June 2018.
  6. 1 2 Staff (2 July 2018). "First confirmed image of newborn planet caught with ESO's VLT - Spectrum reveals cloudy atmosphere". EurekAlert!. Retrieved 2 July 2018.
  7. 1 2 Müller, A; et al. (2018). "Orbital and atmospheric characterization of the planet within the gap of the PDS 70 transition disk". arXiv:1806.11567 [astro-ph.EP].
  8. 1 2 Keppler, M; et al. (2018). "Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70". arXiv:1806.11568 [astro-ph.EP].
  9. ↑ Gregorio-Hetem, J.; Lepine, J. R. D.; Quast, G. R.; Torres, C. A. O.; de La Reza, R. (1992). "A search for T Tauri stars based on the IRAS point source catalog". The Astronomical Journal. 103: 549. Bibcode:1992AJ....103..549G. doi:10.1086/116082.
  10. ↑ Hashimoto, J.; et al. (2015). "The Structure of Pre-Transitional Protoplanetary Disks. II. Azimuthal Asymmetries, Different Radial Distributions of Large and Small Dust Grains in PDS 70". The Astrophysical Journal. 799 (1): 43. arXiv:1411.2587. Bibcode:2015ApJ...799...43H. doi:10.1088/0004-637X/799/1/43.
  11. ↑ Clery, D. (2018). "In a first, astronomers witness the birth of a planet from gas and dust". Science. doi:10.1126/science.aau6469.
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