CME
## Community Coordinated Modeling Center Database Of Notifications, Knowledge, Information ( CCMC DONKI ) ## Message Type: Space Weather Notification - CME (Europa Clipper, OSIRIS-APEX, STEREO A, Missions Near Earth) ## ## Message Issue Date: 2026-04-16T19:38:00Z ## Message ID: 20260416-AL-001 ## ## Disclaimer: NOAA's Space Weather Prediction Center is the United States Government official source for space weather forecasts. This "Experimental Research Information" consists of preliminary NASA research products and should be interpreted and used accordingly. ## Summary: C-type CME detected by STEREO A / GOES / SOHO. Start time of the event: 2026-04-16T09:00Z. Estimated speed: ~677 km/s. Estimated opening half-angle: 16 deg. Direction (lon./lat.): 22/-9 in Heliocentric Earth Equatorial coordinates. Activity ID: 2026-04-16T09:00:00-CME-001 Based on preliminary analysis by the Moon to Mars Space Weather Analysis Office and heliospheric modeling carried out at NASA Community Coordinated Modeling Center, it is estimated that this CME may affect Europa Clipper (glancing blow), OSIRIS-APEX (glancing blow), and STEREO A (glancing blow). The flank of the CME will reach Europa Clipper at 2026-04-21T06:00Z, OSIRIS-APEX at 2026-04-19T04:00Z, and STEREO A at 2026-04-19T05:00Z (plus minus 7 hours). The simulation also indicates that the CME may have a glancing blow at NASA missions near Earth. Simulations indicate that the flank of the CME will reach NASA missions near Earth at about 2026-04-18T14:00Z (plus minus 7 hours). The roughly estimated expected range of the maximum Kp index is 3-5 (below minor to minor). Links to the movies of the modeled event (includes CME: 2026-04-16T09:00:00-CME-001): https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_anim.tim-den.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_anim.tim-vel.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_anim.tim-vel-Stereo_A.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_anim.tim-den-Stereo_A.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_ENLIL_CONE_timeline.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_ENLIL_CONE_STA_timeline.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_ENLIL_CONE_Osiris_timeline.gif https://iswa.ccmc.gsfc.nasa.gov/api/redirect?filename=20260416_131300_2.0_ENLIL_CONE_EuropaClippr_timeline.gif ## Notes: SCORE CME typification system: S-type: CMEs with speeds less than 500 km/s C-type: Common 500-999 km/s O-type: Occasional 1000-1999 km/s R-type: Rare 2000-2999 km/s ER-type: Extremely Rare >3000 km/s
