ToO Information

Request ID: 57077
Request Type: NEW
ToO Urgency: WITHIN A WEEK
Proposal ID:

Target Info

Target Name: GS 1826-238
Target No.:
Category: X-RAY BINARIES
Coordinates[J2000]: (277.37000, -23.79667)
Exp (ks): 20
Extended: N
Extent Size:
Background Restriction: N
Remarks:

Constraint Details

Monitor: Y
Criteria: One 10ks observation within a day (around 28-30 of June), and another 10ks roughly a week later which could be scheduled in coordination with a Chandra DDT request (to be submitted tomorrow).
Phase Dependent: N
Epoch:
Period:
Min:
Max:
Remarks:
Specific Time: Y
Start: 2025-06-28 00:00 UTC
End: 2025-06-30 00:00 UTC
Remarks: The first 10ks should be taken as soon as possible in case the source changes its state back to the soft state. The second 10ks would be optimally scheduled roughly week later together with Chandra (DDT proposal in prep.).
ToO: Y
Coordinate Observation: PREFERRED
Observatory: CHANDRA
Description: We will trigger a 35ks Chandra DDT proposal tomorrow, as Chandra is the only facility to continuously observe the target over the expected 1.6 - 3 hour recurrence period. Chandra visibility starts in June 30, but we do not expect them to react before July 4th.
Uninterrupted: N
Justification:
Estimated Count Rate (cts s-1): 1500.000

Requester Information

Name: DR. JARI JUHA EEMELI KAJAVA

Status

Request Date (UTC): 2025-06-25 16:52:51
Disposition: Rejected
Date: 2025-07-14 15:19:11.889828
Reason: NICER pointing anomaly
Person:
Status: Unable to Execute
Date: 2025-07-14 15:19:11.889828
Person:

Misc

Note:

Target Details

Nearest Target No: 7056
Nearest Taget Name: GS_1826-24
Separation (arcmin): 0.1379
Nearby Target (<3.0'): 2425[GS_1826-24],7056[GS_1826-24]
Referenced Target Catalogue: /Home/eud/nicerweb/too/ags/NICER2_Xray_Target_List_V43o.csv.gz
Sun Angle: 177.2 deg at 2025:176:16:54:12 (UTC), 169.4 deg after 2 weeks

Planned Observations

AGS6 Reference:
Planned Snapshots:

Observation Start Observation End Span Mode Observation ID
(YYYY-DDDTHH:MM:SS) (YYYY-DDDTHH:MM:SS) (seconds) Man/Opt

Visibility

AGS3 Reference:
Visibility Report:

Target Name Target ID Visibility Start Visibility End Span Initial Final Relative
(YYYY-DDDTHH:MM:SS) (YYYY-DDDTHH:MM:SS) (seconds) Interference Interference Orbits