A candidate planetary-mass object with a photoevaporating disk in Orion

TL;DR

This paper reports the discovery of a candidate planetary-mass object with a photoevaporating disk in Orion, likely formed recently in a low-mass cloud near a massive star, with properties similar to young stars in the region.

Contribution

It presents the identification and characterization of a very low-mass, young planetary-mass object with a photoevaporating disk, suggesting a second-generation star formation near a massive star in Orion.

Findings

Object has a mass likely less than 13 Jupiter masses.

Object shows signs of ongoing external photoevaporation.

Object's properties are consistent with a very young age (<0.5 Myr).

Abstract

In this work, we report the discovery of a candidate planetary-mass object with a photoevaporating protoplanetary disk, Proplyd 133-353, which is near the massive star $\theta^{1}$ Ori C at the center of the Orion Nebula Cluster (ONC). The object was known to have extended emission pointing away from $\theta^{1}$ Ori C, indicating ongoing external photoevaporation. Our near-infrared spectroscopic data suggests that the central source of Proplyd 133-353 is substellar ($\sim$M9.5), might have a mass probably less than 13 Jupiter mass and an age younger than 0.5 Myr. Proplyd 133-353 shows a similar ratio of X-ray luminosity to stellar luminosity to other young stars in the ONC with a similar stellar luminosity, and has a similar proper motion to the mean one of confirmed ONC members. We propose that Proplyd 133-353 was formed in a very low-mass dusty cloud near $\theta^{1}$ Ori C as a second-generation of star formation, which can explain both its young age and the presence of its disk.