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We present the discovery of seven new proplyds (i.e. sources surrounded bycometary Halpha emission characteristic of offset ionization fronts) in NGC1977, located about 30' north of the Orion Nebula Cluster at a distance of ~400pc. Each of these proplyds are situated at projected distances 0.04-0.27 pcfrom the B1V star 42 Orionis (c Ori), which is the main source of UV photons inthe region. In all cases the ionization fronts of the proplyds are clearlypointing toward the common ionizing source, 42 Ori, and 6 of the 7 proplydsclearly show tails pointing away from it. These are the first proplyds to befound around a B star, with previously known examples instead being locatedaround O stars, including those in the Orion Nebula Cluster around $\theta^1$Ori C. The radii of the offset ionization fronts in our proplyds are between~200 and 550 AU; two objects also contain clearly resolved central sources thatwe associate with disks of radii 50-70 AU. The estimated strength of the FUVradiation field impinging on the proplyds is around 10-30 times less than thatincident on the classic proplyds in the Orion Nebula Cluster. We show that theobserved proplyd sizes are however consistent with recent models for FUVphotoevaporation in relatively weak FUV radiation fields.

Proplyds around a B1 star - 42 Orionis in NGC 1977