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Chandra Radiation Environment Summary

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

Orbit start: 2025:037:05:09:03 (201.2 ksec in this period)
Current altitude/orbit leg: 83891 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: 2.4
 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 1.001e+03 8.614e+07 8.624e+07
(8.635e+07)
*8.720e+07*		 8.850e+07 9.285e+07 working yellow limit:
1.000E+09 (fluence)
ACE P3 2.460e+01 2.900e+06 2.903e+06
(2.905e+06)
*2.926e+06*		 2.958e+06 3.065e+06 alert trigger: 1.000E+09 (fluence)
GOES-R (P4) 1.766e-02 1.137e+03 1.139e+03 1.179e+03 1.255e+03  
GOES-R (P7) 2.315e-04 6.677e+01 6.680e+01 6.732e+01 6.832e+01  
GOES-R (E>2.0MeV) 3.232e+01 5.004e+06 5.007e+06 5.080e+06 5.220e+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 1.001e+03 1.249e+08 1.250e+08 1.349e+08 1.770e+08  
ACE P3 2.460e+01 2.900e+06 2.903e+06 3.148e+06 4.181e+06 3.6e8 (2 hr fluence, red)
GOES-R (P4) 1.766e-02 1.648e+03 1.650e+03 1.826e+03 2.568e+03 30.0/90.9 (flux, yellow/red)
GOES-R (P7) 2.315e-04 9.679e+01 9.681e+01 9.912e+01 1.088e+02 0.25/0.70 (flux, yellow/red)
GOES-R (E>2.0MeV) 3.232e+01 7.253e+06 7.256e+06 7.579e+06 8.936e+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.