NuSTAR ToO targets approved within the NuSTAR, Chandra, XMM-Newton, Swift, NICER, and IXPE General Observer programs


    NuSTAR Target of Opportunity (ToO) observations may be proposed for in the NuSTAR, Chandra, XMM-Newton, Neil Gehrels Swift Observatory, NICER, and IXPE General Observer (GO) programs.

    A list of proposals selected for the joint NuSTAR/INTEGRAL General Observer (GO) program can be found here.

    Last update: 2025-06-11

      Proposal title and abstracts are available here, or click on the Proposal number in the table below. Note that NuSTAR ToO and DDT observations may be requested at any time through the ToO/DDT observation request form which provides a list of currently active unanticipated ToO/DDT targets.

      Proposals will be marked with an orange background when they are triggered and a green background when they are completed. Targets that have yet to be identified have blank J2000 coordinates.

NuSTAR GO ToO programs
Proposal
PI
ObsIDTarget Name
J2000 RA (deg)
J2000 Dec (deg)
Exposure (ks)
Comments
10097Raffaella Margutti81002425SN2005mvn198.3661708 36.5865861 3x40Coordinated with Swift
Triggered 2025-06-04
10216Javier Garcia810023434U 1630-472248.506708 -47.39303x30 10x20 2x30 3x50Coordinated with NICER
Triggered 2025-04-07
10309Oluwashina Adegoke810023554U 1630-472248.506708 -47.3930 3x25Coordinated with NICER
Triggered 2025-04-07
11016Murray Brightman81101525TRANSIENT ULX0050Coordinated with XMM-Newton
11046Qi Feng81102626CANDIDATE NU BLAZAR002x40Coordinated with Swift & VERITAS
11086Dheeraj Pasham81102627JETTED TDE002x20 + 40Coordinated with NICER
11118Shifra Mandel81102328GC X-RAY TRANSIENT002x20
11129Dheeraj Pasham81101629ICECUBEGOLD0050
11131Vittoria Gianolli81101630NGC4151182.6357539.4058630Coordinated with XMM-Newton and Swift
11133Yuexin Zhang81102331GX 339m4255.70579-48.789753x20Coordinated with NICER
11135Jennifer Sokoloski81102332T CrB239.8756725.920172x20Coordinated with NICER
11139Ole Koenig81101333LMXB BH00100
11140Marina Orio81102334NEW SYMBIOTIC NOVA0020+20Coordinated with XMM-Newton
11149Amruta Jaodand81102735X-BNS00100+75+75
11158Mischa Breuhaus81101636KM3NET BLAZAR0035Coordinated with XMM-Newton
11165Yuexin Zhang81102337GRS 1915p105288.7981710.945812x20Coordinated with NICER IXPE and VLA
11173Dominic Walton81102338NGC5907 ULX1228.9941756.302782x100Coordinated with XMM-Newton
11181Jon Miller81101639MARKARIAN 817219.09258.79428100
81101640PG 1211p143183.5736214.0536780
11187Alice Borghese81102341Magnetar outburst0030+60+80
11193Xiurui Zhao81102642MRK 509311.04063-10.7235320+20Coordinated with Swift
811026431H0419m57766.503-57.200540+20Coordinated with Swift
11203Kaya Mori81101344Long Period Radio Transient0080Coordinated with XMM-Newton and Swift
11209Alessio Marino81101345Faint EP LMXB 10050Coordinated with NICER or EP-FXT
81101346Faint EP LMXB 20050Coordinated with NICER or EP-FXT
11219Federico Vincentelli81160301LMXB 10020Coordinated with NICER and VLT
81160302LMXB 20020Coordinated with NICER and VLT
81160303LMXB 30020Coordinated with NICER and VLT
81160304LMXB 40020Coordinated with NICER and VLT
81160305LMXB 50020Coordinated with NICER and VLT
81160306LMXB 60020Coordinated with NICER and VLT
81160307LMXB 70020Coordinated with NICER and VLT
81160308LMXB 80020Coordinated with NICER and VLT
11258Daniel Lawther81101647MRK59033.63983-0.7667250Coordinated with XMM-Newton
11266Lea Marcotulli81101648VHE gamma-ray source00180Coordinated with XMM-Newton
11282Dheeraj Pasham81102349LONG EP TRANSIENT002x20
11286Mason Ng81102350HIGH B RPP003x50
11287Benjamin Coughenour81101351TRANSIENT BH XRB0050Coordinated with NICER
11304Christian Malacaria81101352New EP pulsar 10050Coordinated with NICER
81101353New EP pulsar 20050Coordinated with NICER
11310Edward Nathan81101354H1743m322266.565-32.2335850Coordinated with NICER
81101355A BRIGHT XRB000Coordinated with NICER
Joint NuSTAR/Chandra GO ToO programs
25400276Kosec81002301LMC/SMC ULX 3x20
25400338Neilsen81002302Black Hole Transient 4x25
25500335Margutti81002403AT2024qfm350.347753 11.942232 2x25 + 2x40Triggered 2024-08-01
26400066Peter Kosec81102301Magellanic Clouds ULX transient 3x20
26400115Kaya Mori81102302MAXI J1744-294266.424708 -29.009722 2x20Triggered 2025-02-03
26400240Joey Neilsen811023034U 1630-472248.506708 -47.3930 4x25Triggered 2025-04-07
26500151Raffaella Margutti81102404Interacting SN 2x50
Joint NuSTAR/XMM-Newton GO ToO programs
090022Norbert Schartel80801601PG 1149-110178.014789-11.37335980Triggered 2024-12-09
80801602RX J0134.7-043023.689583-4.50359780Triggered 2024-12-05
090332Rafaella Margutti80802406AT2024wpp40.522853-16.9563972x25+2x40Triggered 2024-11-14
094004Norbert Schartel81001611RQ AGN outburst 150Coordinated with SALT or HET
094004Norbert Schartel81001612RQ AGN outburst 150Coordinated with SALT or HET
094084Rafaella Margutti81002513SNinteracting2x50
094134Erin Kara81001614Mrk 817219.09195858.79426960Coordinated with HST
094209Michael Nowak810013154U 1957+11299.85004211.70829420
094218Murray Brightman81001516NGC 4045 ULX180.6762081.96925100Coordinated with Swift monitoring
094376Samuel Barnier81002317BH XRB outburst10x20
094484Maxime Parra81002318BH LMXB outburst 10x20Coordinated with Swift monitoring
096056Raffaella Margutti81102409FBOT12x25, 2x40Cycle-24 observations begin 2025-05-01
096105Arianna Miraval-Zanon81101310ms pulsar60Coordinated with NRAO/GBO
Cycle-24 observations begin 2025-05-01
096132Alessandro Papitto81101311accreting ms pulsar110Coordinated with IXPE
Cycle-24 observations begin 2025-05-01
096133Sergio Campana81101512GW counterpart NS merger60Coordinated with HST and NRAO
Cycle-24 observations begin 2025-05-01
096346Nanda Rea81102313magnetar outburst60, 100Cycle-24 observations begin 2025-05-01
096405Eleonora Troja81101514GW afterglow150Cycle-24 observations begin 2025-05-01
Joint NuSTAR/Swift GO ToO programs
1821098Kirill Sokolovsky80801310New Nova40
1821161Maria-Carla Nicotra80801311FRB120
1821161Maria-Carla Nicotra80801312FRB220
1922051Liliana Rivera Sandoval80902423Fast-evolving luminous transient3x20
Joint NuSTAR/NICER GO ToO programs
08005Teruaki Enoto81102315MAGNETAR OUTBURST 20+30+50 NICER cycle-7 observations begin in 2025 March
08079Joseph Neilsen81101316GRS 1915+105 288.798167 10.945806 25 NICER cycle-7 observations begin in 2025 March
08110Alice Borghese81101317Magnetar outburst #1 20 NICER cycle-7 observations begin in 2025 March
08110Alice Borghese81101318Magnetar outburst #2 20 NICER cycle-7 observations begin in 2025 March
08149Paul Draghis81101319BH outburst #1 30 NICER cycle-7 observations begin in 2025 March
08149Paul Draghis81101320BH outburst #2 30 NICER cycle-7 observations begin in 2025 March
08165Riley Connors81101321Black Hole Binary 4x20 NICER cycle-7 observations begin in 2025 March
08172Oluwashina Adegoke81101322Black Hole Binaries 6x20 NICER cycle-7 observations begin in 2025 March
08186Edward Nathan81101323GRS 1915+105 288.79816710.945806 30 NICER cycle-7 observations begin in 2025 March
Joint NuSTAR/IXPE GO ToO programs
02036Svetlana Jorstad81101605LSP/ISP BLAZAR20Coordinated with Swift
02151James Steiner81102306H1743-322266.565-32.233582x20Coordinated with NICER
02156Yash Bhargava81102307AQL X-1287.816920.584972x20Coordinated with NICER
02191Maxime Parra81101308Wind Emitting BH-LMXB 20Coordinated with NICER

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