PSR B0943+10

{{Starbox begin

}}

{{Starbox observe

| epoch = J2000.0

| constell = Leo

| ra = {{RA|09|46|7.31}}

| dec = {{DEC|+09|51|57.3}}

}}

{{Starbox astrometry

| dist_ly = 2,000

| dist_pc = 630 ± 100

}}{{Starbox character

| class = Neutron star

| variable = Pulsar

}}

{{Starbox detail

| mass = 1.5[https://exoplanet.eu/catalog/psr_b0943_10_c--6642/ "The Extrasolar Planets Encyclopaedia Planet PSR B0943+10 c"]

| luminosity = 1.31×10⁻⁵

| temperature = 3.1×10⁶{{efn|Blackbody temperature of a small emitting area at the poles}}

| rotation = 1.1 s

| age_myr = 5{{efn|Characteristic age}}{{cite journal | author=Zang, Bing | author2=Sanwal, Divas | author3=Pavlov, George G. | name-list-style=amp | title=An XMM-Newton Observation of the Drifting Pulsar B0943+10| journal=Astrophysical Journal | volume=624 | issue=2 | pages=L109–L112 | date=2005|doi=10.1086/430522|arxiv = astro-ph/0503423 |bibcode = 2005ApJ...624L.109Z | s2cid=119418646 }}}}

{{Starbox reference

| Simbad = PSR+B0943%2B10

}}

PSR B0943+10 is a pulsar 2,000 light years from Earth in the direction of the constellation of Leo.{{cite web|url=http://www.telegraphindia.com/1130125/jsp/nation/story_16483828.jsp|archive-url=https://archive.today/20130216215613/http://www.telegraphindia.com/1130125/jsp/nation/story_16483828.jsp|url-status=dead|archive-date=February 16, 2013|title=Pune telescope spots Jekyll & Hyde puzzle in sky|author=G.S. Mudur|newspaper=The Telegraph, India|date=25 January 2013|access-date=31 January 2013}} It was discovered at Pushchino in December 1968, becoming the first pulsar discovered by Soviet astronomers.{{cite book |last=Shklovsky |first=Iosif |title=Evrika-70 |publisher=Molodaya Gvardiya |year=1970 |editor1=N. Lazarev |location=Moscow |pages=16 |language=ru |chapter=Rozhdyonnye katastrofoi |author-link=Iosif Shklovsky |editor2=F. Naumov}}{{cite book |url=https://books.google.com/books?id=3DqOARyWib4C&pg=PA45 |title=A Brief History of Radio Astronomy in the USSR. A Collection of Scientific Essays |publisher=Springer |year=2012 |isbn=978-94-007-2833-2 |editor1-last=Braude |editor1-first=S. Y. |series=Astrophysics and Space Science Library. 382 |volume=382 |pages=45 |doi=10.1007/978-94-007-2834-9 |display-editors=etal}} The original designation of this pulsar was PP 0943.[http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=PSR%20B0943%2B10 PSR B0943+10 -- Pulsar] in SIMBAD

Characteristics

The pulsar is estimated to be 5 million years old, which is relatively old for a pulsar.{{cite web|url=http://www.astronomy.com/~/link.aspx?_id=418c617f-ff97-4a7c-b34b-6f6c72ae6049|title=Baffling pulsar leaves astronomers in the dark|author=ESA|publisher=Astronomy.com|date=25 January 2013|access-date=31 January 2013}} It has a rotational period of 1.1 seconds and emits both radio waves and X-rays.{{cite web|url=http://www.space.com/19418-weird-pulsar-defies-theories.html|title=Weird Spinning Star Defies Explanation|author=Elizabeth Howell|publisher=Space.com|date=24 January 2013|access-date=31 January 2013}}

Ongoing research at the University of Vermont discovered that the pulsar was found to flip roughly every few hours between a radio bright mode with highly organized pulsations and a quieter mode with rather chaotic temporal structure.

Moreover, the observations of the pulsar performed simultaneously with the European Space Agency's XMM-Newton X-ray observatory and ground-based radio telescopes revealed that it exhibits variations in its X-ray emission that mimic in reverse the changes seen in radio waves – the pulsar has a weaker non-pulsing X-ray luminosity during the radio bright mode and is actually brighter during the radio quiet mode emitting distinct X-ray pulses.{{Cite journal | last1 = Hermsen | first1 = W. | last2 = Hessels | first2 = J. W. T. | last3 = Kuiper | first3 = L. | last4 = Van Leeuwen | first4 = J. | last5 = Mitra | first5 = D. | last6 = De Plaa | first6 = J. | last7 = Rankin | first7 = J. M. | last8 = Stappers | first8 = B. W. | last9 = Wright | first9 = G. A. E. | last10 = Basu | doi = 10.1126/science.1230960 | first10 = R. | last11 = Alexov | first11 = A. | last12 = Coenen | first12 = T. | last13 = Grießmeier | first13 = J. - M. | last14 = Hassall | first14 = T. E. | last15 = Karastergiou | first15 = A. | last16 = Keane | first16 = E. | last17 = Kondratiev | first17 = V. I. | last18 = Kramer | first18 = M. | last19 = Kuniyoshi | first19 = M. | last20 = Noutsos | first20 = A. | last21 = Serylak | first21 = M. | last22 = Pilia | first22 = M. | last23 = Sobey | first23 = C. | last24 = Weltevrede | first24 = P. | last25 = Zagkouris | first25 = K. | last26 = Asgekar | first26 = A. | last27 = Avruch | first27 = I. M. | last28 = Batejat | first28 = F. | last29 = Bell | first29 = M. E. | last30 = Bell | first30 = M. R. | title = Synchronous X-ray and Radio Mode Switches: A Rapid Global Transformation of the Pulsar Magnetosphere | journal = Science | volume = 339 | issue = 6118 | pages = 436–439 | year = 2013 | pmid = 23349288|arxiv = 1302.0203 |bibcode = 2013Sci...339..436H | s2cid = 2460047 }} Such changes can only be explained if the pulsar's magnetosphere (which may extend up to 52,000 km from the surface) quickly switches between two extreme states. The change happens on a few seconds timescale, far faster than most pulsars. Despite being one of the first pulsars discovered, the mechanism for its unusual behavior is unknown.{{cite web|url=https://www.sciencedaily.com/releases/2013/01/130124150802.htm|title=Chameleon Pulsar Dramatically Changes the Way It Shines|author=Staff|publisher=Sciencedaily.com|date=24 January 2013|access-date=31 January 2013}}

In 2006, a research group from Peking University published a paper suggesting that the pulsar may actually be a low-mass quark star with mass around {{solar mass|0.02}}.{{cite journal | author=Yue, Y. L. | author2=Cui, X. H. | author3=Xu, R. X. | title=Is PSR B0943+10 a low-mass quark star?| journal=Astrophysical Journal |volume = 649| issue=2 | pages=L95 | date=2006 |arxiv = astro-ph/0603468v2|bibcode = 2006ApJ...649L..95Y |doi = 10.1086/508421 | s2cid=18183996 }}

Claimed planetary system

In May 2014, the detection of periodic timing variations was reported that could be explained by two gas giant planets orbiting PSR B0943+10.[https://exoplanet.eu/catalog/psr_b0943_10_b--6641/ "The Extrasolar Planets Encyclopaedia Planet PSR B0943+10 b"] A more recent analysis from 2019 found instead a single, five-Earth mass planet with an orbital period of 12 years.

However, all proposed planets were found to be doubtful in a 2025 publication, which suggest the observed variations are due to magnetospheric phenomena and spin-down oscillations. The planets reported in 2014 are classified as "deprecated", while the planet reported in 2019 is a "questionable candidate".

Notes

References

{{reflist|refs=

{{cite journal | doi=10.1134/S1063772914110067 | title=Detection of regular variations in the intensity and pulse time of arrival of the anomalous pulsar PSR B0943+10 | date=2014 | last1=Suleymanova | first1=S. A. | last2=Rodin | first2=A. E. | journal=Astronomy Reports | volume=58 | issue=11 | pages=796–807 | bibcode=2014ARep...58..796S | s2cid=255196382 }}

{{cite journal |last1=Laycock |first1=Silas G. T. |last2=Christodoulou |first2=Dimitris M. |date=March 2025 |title=On the Number of Confirmed Pulsar Planets: The Rule of Six |journal=The Astrophysical Journal |volume=982 |issue=1 |pages=63 |doi=10.3847/1538-4357/adb1a8 |doi-access=free}}

{{Cite journal |last=Starovoit |first=E. D. |last2=Suleymanova |first2=S. A. |date=2019-04-01 |title=A 12-Year Periodicity in the Pulse Arrival Times for the Pulsar PSR B0943+10 |url=https://ui.adsabs.harvard.edu/abs/2019ARep...63..310S/abstract |journal=Astronomy Reports |volume=63 |pages=310–315 |doi=10.1134/S1063772919030107 |issn=1063-7729}}

}}

Category:Leo (constellation)

Category:Pulsars

Category:Stellar phenomena

Category:Hypothetical planetary systems