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Simin Tong

@simintong.bsky.social

PhD student @UoLeicester| Protoplanetary Disk & Planet Formation | A beginner theorist but always an observer of everyday life. Personal Website: simintong.github.io/home

Posts Replies Media

Simin Tong @simintong.bsky.social · 07/09/2026

Finally, Serpens still has a few surprises 👀 We identify two protoplanetary disks with very large inner cavities (~90 au), including one with a strong asymmetry. What created these structures? We still don’t know. 🧵(n/n)

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Simin Tong @simintong.bsky.social · 07/09/2026

Disks in Ophiuchus and Corona Australis appear unexpectedly low in dust masses for their young ages (Cazzoletti+2019; Williams+2019). However, when we only consider high-confidence members in a given region identified by Gaia, their dust masses are broadly consistent with their ages. (7/n)

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Simin Tong @simintong.bsky.social · 07/09/2026

We revisited the stellar densities of nearby star-forming regions using Gaia distances for individual stars. This allows us to measure their 3D stellar densities, rather than the projected 2D surface densities. We find that Serpens is much less dense in 3D. (4/n)

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Simin Tong @simintong.bsky.social · 07/09/2026

But our survey, along with the earlier study led by Alexa Anderson, finds that the dust disk masses in Serpens are similar to those in Lupus and Taurus, two young regions with much lower stellar densities (Fig 6 in Anderson+2022). So, is Serpens really that dense? (3/n)

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Simin Tong @simintong.bsky.social · 07/09/2026

Serpens has long been considered denser than many nearby young star-forming regions (e.g. Megeath+2016, their Fig. 15). Such high stellar densities could lead to more frequent encounters between star–disk systems, potentially truncating disks and reducing their dust masses. (2/n)

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