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 | |
| SIMBAD | data |
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]
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] In 2024, a study refined our knowledge of the planet's physical and orbital properties, finding that its mass is approximately 0.0041±0.003 M🜨, or about 30% that of the Moon, making it one of the least massive known objects outside the solar system. Its orbital parameters have been more thoroughly established, showing that it is on a slightly eccentric orbit lasting 3,310 days (or just over 9 years) which is also severely inclined relative to the plane of the triple system's orbit, suggesting it may have arrived there via influence from a Kozai mechanism.[10]
Since PSR J0337+1715 (AB) b's orbit is relatively stable (for at least 100 million years), it may possibly be the last surviving member of a population of small objects which were formed after the progenitor of the pulsar in this system became a red supergiant, engulfing one of the two other stars and creating a common envelope between it and said star. The engulfed star was slowed down from the common envelope gas, transferring its orbital energy to that gas, causing it to expand and be expelled from the star, settling into a circumbinary disk where many small objects condensed from this gas. Of those, only PSR J0337+1715 (AB) b is still present, as all the others were on less stable orbits which likely got them ejected from the system or crashing into one of the stars.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| PSR J0337+1715 (AB) b (unconfirmed) | 0.0041 M🜨 | 5.52 | 3,310 days | 0.257 | 119° | — |
References
[edit]- ^ "Einstein's theory of relativity passes its toughest test yet". NBC News. 5 July 2018.
- ^ 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.
- ^ "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.
- ^ "Bold Experiments Will Put General Relativity to the Test | DiscoverMagazine.com". Discover Magazine. Retrieved 2016-10-12.
- ^ 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.
- ^ 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.
- ^ "Scientists Test Einstein's Theory of Gravity on Unique Triple-Star System". Sci-News. Jul 5, 2018.
- ^ 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.
- ^ 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]
- ^ a b Voisin, Guillaume; Cognard, Ismaël; Saillenfest, Melaine; Tauris, Thomas; Wex, Norbert; Guillemot, Lucas; Theureau, Gilles; Freire, P. C. C.; Kramer, Michael (2024-11-15), Explanation of the exceptionally strong timing noise of PSR J0337+1715 by a circum-ternary planet and consequences for gravity tests, doi:10.48550/arXiv.2411.10066, retrieved 2024-12-12
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