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

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

    Last update: 2020-07-06

      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
ObsIDTarget Name
J2000 RA (deg)
J2000 Dec (deg)
Exposure (ks)
05213Tomsick80502324MAXI J0637-43099.09828-42.8678010x50Large Program
Triggered 2019-11-13
05252Vestergaard80502630Mrk 59033.63992 -0.7667560,50,40Joint with 70 ks Gehrels-Swift observations
1st observation triggered 2019-08-30
06027Krucker80610201Quiet Sun17142x251st observation on 2020:256
06045Ballhausen80601301New CRSF source 40
06074Jiang80601302Black Hole Transient 30
06086Bozzo80601316New INTEGRAL transient 30Joint with 30 ks XMM-Newton observation
06091Miller80601601TDE 50
06121Doroshenko80660301SRGA J124402.9-632235191.01579 -63.37543 50New eROSITA XRB1
Triggered 2021-01-28
06121Doroshenko80660302New eROSITA XRB2 50
06133Ballhausen80601306HXMB CRSF 100
06156Krauss806616011RXS J093117.6+033146142.824196 3.522092 40Triggered 2020-06-16
06156Krauss80661602ICECUBE follow-up 2 40
06164Sokolovsky80601317MGAB-V20759.62313 -54.77811 60Triggered 2020-07-16
Joint with 20 ks XMM-Newton observation
06165Krumpe80662601eROSITA AGN 1 70
06165Krumpe80662602eROSITA AGN 2 70
06165Krumpe80662603eROSITA AGN 3 70
06165Krumpe80662604eROSITA AGN 4 70
06166Gokus80601602PKS 0537-28684.976173 -28.665541 100Triggered 2020-12-22
06197Walton80602308Holmberg IX X-1149.4720469.063394x50Joint with 4x25 ks XMM-Newton observations and 52 ks Swift monitoring
Multi-cycle program
Triggered 2020-10-14
06209Vasilopoulos80602501MC transient 25+25+50
06214Pike80601502Circinus ULX5213.1625-65.39278100Joint with 23 ks Swift monitoring observations
Triggered 2020-11-20
06217Cerruti80601603VHE Quasar 40
06222Sanna80601309IGR J17494-3030267.350 -30.50 50Triggered 2020-10-27
Joint with 21 ks NICER observation
06238Vestergaard80602604Mrk 59033.63992-0.7667550+40+30Joint with 3x25 ks XMM-Newton and 3x10 ks Swift observations
Multi-cycle program
06244Roberts80601310PSR J2129-0429 322.43871-4.48664100Joint with 30 ks Swift monitoring observations
Joint NuSTAR/Chandra GO ToO programs
21400516K Mori80602301Galactic Center transienttbdtbd2x20
22400400K Mori80702304Galactic Center VFXTtbdtbd2x20
22400529M Bachetti80701305M82 X-2148.96266769.67930380
22500172P Scholz80701506FRB 20200120E149.485068.818027Triggered 2020-12-02
Coordinated with Effelsberg 100m
22500192D Matthews80701407AT2020xnd
(Fast Blue Optical Transient)
335.008458-2.84036112x25, 2x40Triggered 2020-10-26
Joint NuSTAR/XMM-Newton GO ToO programs
078214Felix Fuerst80201011BH ToO 40Coordinated with 10 x 2 ks Swift observations. Program extended into cycle-17
078430Nanda Rea80202013XTE J1810-197272.46 -19.731 20+30+40+80Observations to be obtained over ~3 months. Triggered 2018-12-20
082145Alessandro Papitto80401306ms pulsar 60
082359Nanda Rea80402308Swift J1818.0-1607274.5009167 -16.1311944 20,30,40,80Triggered 2020-03-20
084079Fiona Harrison80501303BH hard state 40
084080Norbert Schartel80502606NGC 156665.00167-54.937805650Triggered 2019-05-30
084080Norbert Schartel80502607IRAS 23226-3843351.350833-38.44694450Triggered 2019-10-16
084355Raffaella Margutti80502405Fast blue optical transient 2x25 + 2x40
084377Norbert Schartel80501606AGN minimum 80
084434Jelle Kaastra80502609NGC 3227155.877519.86502x25Triggered 2019-11-11
084469Jian Li80501608muon track neutrino 40
084526Luigi Piro80501609GW event 150
084545James Court80502310GRO J1744-28266.137875-28.74083380
086127Allesandro Papitto80601304transitional ms pulsar60
086276Hannah Earnshaw8061305NGC 925 ULX-336.86458333.570278100Triggered 2020-08-11
086342Raffaella Margutti80602406SN2019yvr191.28389-0.459092x50Triggered 2020-06-18
086403Jennifer Sokoloski80602307T CrB239.87566725.92016750Triggered 2020-08-27
086460Nanda Rea80602315PSR J1846-0258281.60391667-2.9750277823,30,40,80Triggered 2020-08-02
088008Norbert Schartel80701608AGN outburst2x50
Coordinated with SALT or HET
088054Pierre-Olivier Petrucci80702310BH LMXB10x20
088218Nanda Rea80702311Magnetar outburst
088470Alessandro Papitto80701312accreting ms pulsar120
Coordinated with IXPE
Joint NuSTAR/INTEGRAL GO ToO programs
1740029Riccardo La Placa80601314Millisecond X-ray pulsar30Also coordinated with XMM-Newton
1740033Julia Alfonso-Garzon80501302H 1145-619177.000083-62.206916725Also coordinated with Swift
1840002Thomas Siegert80701501NS merger100
1840005Zhaosheng Li80701302Accreting ms pulsar30
Also coordinated with XMM-Newton, NICER, and HXMT
1840021Ingo Kreykenbohm80701303Accreting X-ray pulsar40
Joint NuSTAR/Swift GO ToO programs
1619112Luigi Piro80601509Fast Radio burst 1tbd tbd 20
1619112Luigi Piro80601510Fast Radio burst 2tbd tbd 20
1619139Liliana Sandoval80602511Fast-Evolving Luminous Transienttbd tbd 3x20
Joint NuSTAR/NICER GO ToO programs
03056Teruaki Enoto 80602312Magnetar Outburst 20+30+50
03155Alice Borghese 80602313SGR 1935+2154293.732021.8967220+20+30+40Triggered 2020-04-28
04060Teruaki Enoto 80702313Magnetar Outburst 20+30+50
04099Fiamma Capitanio80702314Transient black hole XRB 2x30 + 20
04118Jingyi Wang80702315Unknown BHB 3x20
04152Navin Sridhar80702316Unknown XRB 3x20
04155Riley Conners80702317Black hole binary 4x20
04163Jeroen Homan807023184U 1820-30 275.91904-30.3612783x20
04181Gugleilmo Mastroserio80701319Unknown XRB 30

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