# Hubble STIS detects the visible-light scattered component of the Cat's Tail dust in the β Pictoris disk

- Published: 2026-11-14 21:51 UTC
- Section: Sky & Space › Astronomy
- Tags: β Pictoris debris disk, Cat's Tail dust, Hubble STIS coronagraph, scattered light imaging, porous organic grains, JWST MIRI, Kuiper Belt analogs, planet–disk interaction, dust halo asymmetry
- URL: https://realtech.media/news/rt-5637ae775e092b67bc806d1b_hubble_stis_detects/

**Hubble's STIS coronagraph detected scattered light from the Cat's Tail in the β Pictoris disk. By the authors' model, its grains are highly porous and almost entirely organic.**

![Hubble STIS detects the visible-light scattered component of the Cat's Tail dust in the β Pictoris disk](https://realtech.media/media/2026/11/bf1d5a556ffc29d3.webp)
*science-et-vie.com*

A team working with the coronagraph of the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope reported the visible and near-infrared scattered-light component of the Cat's Tail, a dust substructure in the debris disk of β Pictoris. The study appeared in The Astrophysical Journal Letters. [1] The star is located 63 light-years from Earth. The authors combined six epochs of observations made between 2012 and 2025. [1]

The Cat's Tail was first resolved in the mid-infrared by JWST/MIRI, so the new data add a second wavelength range to the picture of this structure. [1]

## Disk detection and grain properties

With STIS, the disk was detected out to a projected separation of 500 au for the first time. Across much of the midplane between 50 and 200 au the signal-to-noise ratio exceeds 100. [1]

Injection-recovery analysis showed that the scattered-light component of the Cat's Tail has a total flux of 0.1%–0.4% of the MIRI F1550C flux. [1] Using the measured STIS-to-MIRI flux ratio, the authors modeled the properties of the grains. In their model the grains are highly porous and almost entirely composed of organic refractory material, which agrees with the JWST/MIRI results. [1]

## Progenitor mass and outer halo

To estimate the size of the colliding bodies, the authors used the organics content of solar system dwarf planets and of dust in the local interstellar medium as a proxy. On this basis each colliding progenitor must have a mass of at least 1–3 × 10²¹ kg, comparable to Charon and Makemake in the Kuiper Belt. [1]

The images also show a prominent warped morphology and a surface brightness asymmetry in the outer dust halo of β Pictoris. [1] The authors compared the observed halo shape and asymmetry with predicted vertical structures that may arise from planet–disk interactions. [1]

The result is based on imaging and modeling of the scattered light. The authors' estimates of grain composition and progenitor mass rely on the assumptions of that model and on the proxies chosen for the organics content. [1]

## Sources

1. [The Astrophysical Journal Letters](https://doi.org/10.3847/2041-8213/aeac4a)
2. [science-et-vie.com](https://www.science-et-vie.com/ciel-et-espace/le-telescope-hubble-a-observe-un-nuage-de-poussiere-long-de-150-milliards-de-kilometres-il-pourrait-provenir-dune-collision-entre-deux-corps-planetaires-266160.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-5637ae775e092b67bc806d1b_hubble_stis_detects/