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Chandra Radiation Environment Summary

See about rad_summ for the definition and origin of the values below.

Orbit start: 2025:037:05:12:06 (201.0 ksec in this period)
Current altitude/orbit leg: 83583 D (km)
Current configuration: ACIS-I NONE
Next comm: 2025:039:15:49:00 (2.8 hours)
Next rad zone: 2025:039:13:03:00 (0.0 hours)
Last updated: 2025:039:13:02:00

(all times on this page are UTC)

 Attenuated - projects fluences based on upcoming SI and grating configuration
ACIS effective exposure times (ks)     Until next radzone: 0.1     Until next comm: 2.3
 Current FluxCurrent fluence
(total so far in current orbit)		 Projected fluence
until next rad zone		 Projected fluenceProjected fluenceLimits
 (p/cm^2-s-sr-MeV)(p/cm^2-sr-MeV) at current flux
(at 2X flux)
*at 10X flux*		 until next comm.until second comm. 
CRM 8.963e+02 8.193e+07 8.201e+07
(8.208e+07)
*8.271e+07*		 8.402e+07 8.792e+07 working yellow limit:
1.000E+09 (fluence)
ACE P3 2.460e+01 2.900e+06 2.902e+06
(2.904e+06)
*2.922e+06*		 2.958e+06 3.065e+06 alert trigger: 1.000E+09 (fluence)
GOES-R (P4) 1.177e-02 1.102e+03 1.103e+03 1.129e+03 1.180e+03  
GOES-R (P7) 2.315e-04 6.459e+01 6.461e+01 6.514e+01 6.614e+01  
GOES-R (E>2.0MeV) 3.232e+01 4.837e+06 4.840e+06 4.913e+06 5.053e+06  
 
 External - does not take into account the instrument configuration
 Current FluxCurrent fluence
(total so far in current orbit)		 Projected fluenceProjected fluence Limits
 (p/cm^2-s-sr-MeV) (p/cm^2-sr-MeV)until next radzone
(total for current orbit)		 until next comm.until second comm. 
CRM 8.963e+02 1.228e+08 1.229e+08 1.319e+08 1.695e+08  
ACE P3 2.460e+01 2.900e+06 2.902e+06 3.147e+06 4.181e+06 3.6e8 (2 hr fluence, red)
GOES-R (P4) 1.177e-02 1.652e+03 1.653e+03 1.770e+03 2.265e+03 30.0/90.9 (flux, yellow/red)
GOES-R (P7) 2.315e-04 9.686e+01 9.688e+01 9.919e+01 1.089e+02 0.25/0.70 (flux, yellow/red)
GOES-R (E>2.0MeV) 3.232e+01 7.253e+06 7.256e+06 7.578e+06 8.935e+06  

The current fluence is calculated from the beginning on the current orbit. The ACE P3 external fluence starts integrating above 10 kkm.
* EPHIN "fluxes" are raw counts as of the last support [ 2025:039:12:11:00 (Feb ], not averaged.

Attenuated CRM Proton Fluence

Green liness indicates fluence estimates based on the current KP value.