arXiv News

First-hand information for everyone

Site

AboutPrivacy PolicyTerms of Use

© 2026 arXiv News

arXiv News

EnglishJapanese

Switch language

EnglishJapanese
Loading account…

First-hand information for everyone

Back to front page
High Energy Astrophysical PhenomenaEnglishPublished

GRS 1915+105’s jet swings 57 ± 8° during X‑ray obscuration

November 4, 2026arXiv: 2611.03395v1

A team of astronomers tracked the powerful jet of the microquasar GRS 1915+105 with very long baseline interferometry during a period in which the system’s X‑ray emission was heavily obscured. Four high‑resolution observations – one with the Very Long Baseline Array and three with the European VLBI Network – were carried out between 2019 and 2021. The jet’s orientation on milliarcsecond scales changed dramatically. In the most extreme case the jet direction was measured 57 ± 8° away from the normal, pre‑obscuration axis that was previously defined as 142 ± 7°. The offsets varied among the epochs, from a compact source with a large deviation, to a flaring source with a comparable shift, to a more extended jet whose position angle was closer to the older mean, and finally to a non‑detection. The team found no evidence for rapid swings of the position angle within individual 8‑hour observing windows, effectively ruling out rapid Lense–Thirring precession of the inner accretion disc as the driver of the observed jet re‑orientation. The pattern of changes instead points to longer‑term processes, such as a radiation‑driven warp in the accretion disc, that could both cause the persistent obscuration and steer the jet over months.

Table summarising measured jet position angles for each VLBI epoch together with the pre‑obscuration weighted mean and its uncertainty, illustrating the largest offset of 57° ± 8°.
EpochMJDPA (∘)Instrumentνc (GHz)References
1994 Jan 2949381159±8VLA8.4Rodríguez and Mirabel (1999)
1994 Feb 1949402157±6VLA8.4Rodríguez and Mirabel (1999)
1994 Mar 1949430149±4VLA8.4Rodríguez and Mirabel (1999)
1994 Apr 2149463147±6VLA8.4Rodríguez and Mirabel (1999)
1994 Apr 2349465149.7±0.7VLA8.4Rodríguez and Mirabel (1999)
1995 Aug 1049939140±10VLA8.4Rodríguez and Mirabel (1999)
1997 Oct 2350744157±2VLBA15Dhawan et al. (2000)
1997 Oct 3150752133±2VLBA2.3Dhawan et al. (2000)
1997 Nov 650758142±2MERLIN5.0Fender et al. (1999)
1998 Apr 1150914155±2VLBA15Dhawan et al. (2000)
1998 May 250935154±4VLBA15Dhawan et al. (2000)
2006 Feb 853794144.1±1VLBA8.4Miller-Jones et al. (2007)
2006 Feb 853794140.1±1VLBA2.3Miller-Jones et al. (2007)
2006 Feb 1253798143.4±1VLBA8.4Miller-Jones et al. (2007)
2006 Feb 1453800145.3±1VLBA8.4Miller-Jones et al. (2007)
2006 Feb 1453800138.5±1VLBA2.3Miller-Jones et al. (2007)
2006 Feb 1753803150.7±1VLBA8.4Miller-Jones et al. (2007)
2006 Apr 2153846140±2eEVN5.0Rushton et al. (2007)
2013 May 2456436130±1VLBA22Reid et al. (2014)
2015 Mar 557086140±8VLA2215A-460 (PI: A. King)
2019 Oct 125876815.3±1.2VLBA8.4This paper
2020 Oct 305915218.61±0.03EVN4.9This paper
2021 Mar 559278170.9±0.3EVN4.9This paper
2023 Apr 156004912±1EAVN6.7Jiang et al. (2026)
2023 Apr 1660050158±7EAVN43Jiang et al. (2026)
2023 Apr 17600516±1EAVN6.7Jiang et al. (2026)
2023 Apr 1960053146±4EAVN43Jiang et al. (2026)
2023 Apr 23600576±1EAVN6.7Jiang et al. (2026)
2023 May 2360088138±9VLA5.5SS192168 (PI: A. Shaw)
2023 Sep 3060217148±3VLA10Jiang et al. (2026)
2023 Sep 3060217.5174.3±0.5VLA8.023B-314 (PI: S.E. Motta)
2024 May 2560455152±1VLA5.524A-474 (PI: S.E. Motta)
2024 Jun 2360484149±1VLA5.524A-474 (PI: S.E. Motta)
2025 Jan 1860693118±7EAVN6.7Yan et al. (2026a)
2025 Jan 2560700131±6EAVN6.7Yan et al. (2026a)
2025 Feb 2460730152±2EAVN6.7Yan et al. (2026a)
Table 3. Post‑obscuration jet position angles from VLBI compared to the pre‑obscuration mean of 142° ± 7°, showing a maximum offset of 57° ± 8°.de Regt, L. I., Atri, P., Motta, S. E., Fender, R. P., Miller-Jones, J. C. A., Williams-Baldwin, D. R. A. · arXiv:2611.03395v1 · Table 3: · CC BY 4.0
Table detailing the observing parameters for each of the four VLBI sessions: instrument, proposal code, observation date, source time, frequency, bandwidth, and beam size.
InstrumentProposal CodeDateTsourceTimeνcBandwidthSynthesized beam
(minutes)(UTC)(GHz)(MHz)(mas × mas, ∘ N to E)
VLBAaBM5002019-10-12260.920:48 – 03:48c8.42561.03 × 2.39, 171.35
EVNbEM144A2020-10-30235.512:30 – 20:304.92561.39 × 3.50, 6.84
EVNbEM144B2021-03-05235.504:00 – 12:004.92562.49 × 3.11, 67.21
EVNbEM144C2021-06-17235.521:30 – 05:304.92561.49 × 2.83, 9.69
Table 1. Observation log of the four VLBI epochs conducted between 2019 and 2021, listing instrument, proposal code, date, on‑source time, central frequency, bandwidth, and synthesised beam.11 1 Notes. $a$$a$footnotetext: VLBA participating stations: Sc, Hn, Nl, Fd, La, Pt, Kp, Ov, Br, and Mk.$b$$b$footnotetext: EVN participating stations: Jb, Ef, Wb, Mc, O8, T6, Ur, Tr, Yb, Hh, Sv, Zl, Bd, Ir, and e-MERLIN stations Cm, Da, De, Kn, and Pi.$c$$c$footnotetext: Times denote on-source time and exclude the 30-min geodetic blocks at the start and end of the VLBA observation. $a$$a$footnotetext: VLBA participating stations: Sc, Hn, Nl, Fd, La, Pt, Kp, Ov, Br, and Mk. $b$$b$footnotetext: EVN participating stations: Jb, Ef, Wb, Mc, O8, T6, Ur, Tr, Yb, Hh, Sv, Zl, Bd, Ir, and e-MERLIN stations Cm, Da, De, Kn, and Pi. $c$$c$footnotetext: Times denote on-source time and exclude the 30-min geodetic blocks at the start and end of the VLBA observation.de Regt, L. I., Atri, P., Motta, S. E., Fender, R. P., Miller-Jones, J. C. A., Williams-Baldwin, D. R. A. · arXiv:2611.03395v1 · Table 1: · CC BY 4.0

Source paper

Milliarcsecond-scale jet reorientations in GRS 1915+105 pointing towards a warped accretion disc

High Energy Astrophysical Phenomena
View on arXiv
GRS 1915+105’s jet swings 57 ± 8° during X‑ray obscuration | arXiv News