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We present the observations of the reflection nebulae IC4954 and IC4955region with the Infrared Camera (IRC) and the Far-Infrared Surveyor (FIS) onboard the infrared astronomical satellite AKARI during its performanceverification phase. We obtained 7 band images from 7 to 160um with higherspatial resolution and higher sensitivities than previous observations. Themid-infrared color of the S9W (9um) and L18W (18um) bands shows a systematicvariation around the exciting sources. The spatial variation in themid-infrared color suggests that the star-formation in IC4954/4955 isprogressing from south-west to north-east. The FIS data also clearly resolvetwo nebulae for the first time in the far-infrared. The FIS 4-band data from65um to 160um allow us to correctly estimate the total infrared luminosity fromthe region, which is about one sixth of the energy emitted from the existingstellar sources. Five candidates for young stellar objects have been detectedas point sources for the first time in the 11um image. They are located in thered S9W to L18W color regions, suggesting that current star-formation has beentriggered by previous star-formation activities. A wide area map of the size ofabout 1 x 1 (deg^2) around the IC4954/4955 region was created from the AKARImid-infrared all-sky survey data. Together with the HI 21cm data, it suggests alarge hollow structure of a degree scale, on whose edge the IC4954/4955 regionhas been created, indicating star formation over three generations in largelydifferent spatial scales.

AKARI infrared imaging of reflection nebulae IC4954 and IC4955