PSR J0337+1715 is a millisecond pulsar discovered in a Green Bank Telescope drift-scan survey from 2007. It is spinning nearly 366 times per second, 4200 light years away in the constellation Taurus. It is the first pulsar found in a stellar triple system. It is co-orbiting very closely with another star, a 0.2 solar-mass white dwarf, with a period of 1.6 days. There is a second white dwarf further out (within one astronomical unit) which is orbiting both the pulsar and the inner white dwarf, and has an orbit with a period of 327 days and a mass of 0.4 solar masses.[1][2] The fact that the pulsar is part of a triple system provides an opportunity to test the nature of gravity and the strong equivalence principle, with a sensitivity several orders of magnitude greater than before.[3][4][5]

PSR J0337+1715
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Taurus
Right ascension 03h 37m 43.82589s
Declination +17° 15′ 14.8280″
Characteristics
Spectral type Pulsar
Details
Other designations
PSR J0337+1715
Database references
SIMBADdata

Results were published in 2018 showing that if there is any departure from the equivalence principle it is no more than three parts per million[2][6][7] at 95% confidence level, improved to two parts per million in 2020.[8]

Planetary system

edit

In 2022 evidence for a small planet with a mass comparable to that of the Moon on a wide orbit was found.[9]

The PSR J0337+1715 planetary system
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
PSR J0337+1715 (AB) b (unconfirmed) 0.01-0.02 M🜨 ~ 3000 days

References

edit
  1. ^ "Einstein's theory of relativity passes its toughest test yet". NBC News. 5 July 2018.
  2. ^ a b Anne, Archibald; et al. (Jul 4, 2018). "Universality of free fall from the orbital motion of a pulsar in a stellar triple system". Nature. 559 (7712): 73–76. arXiv:1807.02059. Bibcode:2018Natur.559...73A. doi:10.1038/s41586-018-0265-1. PMID 29973733. S2CID 56322222.
  3. ^ "Triple-Star System Can Give Clues to True Nature of Gravity | Astronomy | Sci-News.com". Breaking Science News | Sci-News.com. Retrieved 2016-10-12.
  4. ^ "Bold Experiments Will Put General Relativity to the Test | DiscoverMagazine.com". Discover Magazine. Retrieved 2016-10-12.
  5. ^ Ransom, S. M.; Stairs, I. H.; Archibald, A. M.; Hessels, J. W. T.; Kaplan, D. L.; van Kerkwijk, M. H.; Boyles, J.; Deller, A. T.; Chatterjee, S. (2014-01-01). "A millisecond pulsar in a stellar triple system". Nature. 505 (7484): 520–524. arXiv:1401.0535. Bibcode:2014Natur.505..520R. doi:10.1038/nature12917. ISSN 0028-0836. PMID 24390352. S2CID 4468698.
  6. ^ Leah Crane (Jul 7, 2018). "Einstein's theory passes triple-star test". New Scientist. 239 (3185): 9. Bibcode:2018NewSc.239....9C. doi:10.1016/S0262-4079(18)31185-0. S2CID 126337188.
  7. ^ "Scientists Test Einstein's Theory of Gravity on Unique Triple-Star System". Sci-News. Jul 5, 2018.
  8. ^ Voisin, G.; Cognard, I.; Freire, P. C. C.; Wex, N.; Guillemot, L.; Desvignes, G.; Kramer, M.; Theureau, G. (2020-06-01). "An improved test of the strong equivalence principle with the pulsar in a triple star system". Astronomy & Astrophysics. 638: A24. arXiv:2005.01388. Bibcode:2020A&A...638A..24V. doi:10.1051/0004-6361/202038104. ISSN 0004-6361. S2CID 218486794.
  9. ^ Voisin, Guillaume; Luth, G.; Cognard, I.; Freire, P.; Wex, N.; Guillemot, L.; Desvignes, G.; Kramer, M.; Theureau, G.; Saillenfest, M. (2022). "One pulsar, two white dwarfs, and a planet confirming the strong equivalence principle". arXiv:2205.09345 [astro-ph.HE]. [1]