Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2610.30115

Predictions for an unseen third planet in the WISPIT 2 system

Amena Faruqi·Farzana Meru·Gabriel-Dominique Marleau·Pooneh Nazari·Andrew Swan·Ralph E. Pudritz·Thomas G. Wilson
View original source ↗Read source document ↗Export metadata ↓

Abstract

We predict the mass and semi-major axis of a currently unseen but hypothesised planet in the WISPIT 2 system based on the location of the ring observed by ALMA at 144.4 au. Using findings from previous hydrodynamical models, we predict that a ~0.2-1 $M_{Jup}$ planet may exist at ~ 100-120 au. We also demonstrate that the ring seen in VLT/SPHERE observations at 96.7 au is consistent with the mass and semi-major axis of WISPIT 2b and confirm that WISPIT 2b cannot be the cause of the ALMA ring. We also discuss how future observations of the system's gas component may help constrain these predictions better, and note that this third planet in WISPIT 2 may be discoverable using upcoming JWST/NIRCam observations or Gaia data release 4 (DR4).

Explore related subjects

astro-ph.EP

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Amena Faruqi, Farzana Meru, Gabriel-Dominique Marleau, Pooneh Nazari, Andrew Swan, Ralph E. Pudritz, Thomas G. Wilson. 2026-10-21. Predictions for an unseen third planet in the WISPIT 2 system. https://arxiv.org/abs/2610.30115

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

A Formation-Stage Bottleneck for Exomoons around Close-in Rocky Planets

Massive moons around rocky exoplanets are expected outcomes of giant impacts, yet no exomoon has been securely confirmed. We address this problem using meshless finite-mass simulations of giant impacts between differentiated rocky planets that include stellar tidal and Coriolis forces in a local co-rotating frame for orbital periods of 1--300 days, and compare these simulations with otherwise identical collisions in isolation. We find that stellar perturbations impose a severe formation-stage bottleneck on moon-forming disks. Ultra-short-period impacts leave essentially no surviving circumplanetary disk, whereas 10-day systems retain only strongly depleted, radially truncated, and dynamically compact disks. High impact velocities, expected for close-in planets, are devastating for disk generation, while retrograde impacts can slightly compensate for disk mass depletion. These results show that stellar perturbations can suppress exomoon formation around close-in rocky planets, reshaping expectations for the demographics of exomoons.

astro-ph.EP↗
arXiv2026

Emission spectroscopy of KELT-2A b with Gemini-North/IGRINS-2: hints of a stellar C/O ratio and sub-stellar metallicity

We present the results of high-resolution emission spectroscopy of the hot Jupiter KELT-2A~b using IGRINS-2 on the Gemini-North telescope, covering the $H$- and $K$-bands at a spectral resolution of $R \sim 45{,}000$. Observations were carried out over five nights, covering both pre- and post-eclipse orbital phases. Stellar and telluric contaminations are removed via singular value decomposition. We detect $\rm H_2O$ at a signal-to-noise ratio of {6.57}, confirming the previous result at a higher significance. While $\rm ^{12}CO$ is identified in the log-likelihood map near the expected planetary velocity, a definitive detection of $\rm ^{12}CO$ remains elusive given the current data quality. We perform atmospheric retrieval both with IGRINS-2 data alone and jointly with archival \textit{Spitzer}/IRAC photometric data points. The retrieved temperature--pressure profile is non-inverted, consistent with prior observations. {From the joint fit we constrain the water abundance to} $\rm log(H_2O) = {-3.78^{+0.27}_{-0.20}}$ {with the free chemistry model}. {The chemical equilibrium model yields} $\rm C/O={ 0.19^{+0.12}_{-0.07}}$, $\rm [C/H]=-0.81^{+0.41}_{-0.34}$, and $\rm [O/H] = -0.37^{+0.27}_{-0.17}${: the C/O ratio agrees with the stellar value, while the carbon and oxygen abundances are moderately depleted relative to the host star, though still consistent at the $\sim2σ$ level.} If confirmed, {this combination of a stellar C/O ratio with a sub-stellar metallicity is difficult to reconcile with gas accretion between the $\rm{H_2O}$ and CO snowlines, which predicts a super-stellar C/O. It instead points to the accretion of metal-depleted gas outside the CO snowline with only limited planetesimal enrichment, and hence to a disk-free, high-eccentricity migration history.}

astro-ph.EP↗
arXiv2026

Surface regolith model of near-Earth asteroid (3200) Phaethon

The near-Earth asteroid (3200) Phaethon displays activity as it comes close to the Sun and is presumed to be the progenitor of the Geminids meteor shower. Both CM- and CY-meteorites have been suggested as possible meteorite analogues for Phaethon. Previous spectral and polarization measurements of Phaethon indicate possible surface heterogeneity in the regolith properties. By combining mineral components and their size fractions, we present a regolith model for Phaethon that reproduces the spectral, polarization, and geometric albedo measurements presented in various studies, with the aim of quantitatively characterizing the surface material and structure, as well as the regolith heterogeneity. The best fit model able to produce the measurements is constructed from large olivine particles with troilite inclusions and small scale surface roughness, mixed with smaller, porous troilite aggregates comprised of monomers resembling interplanetary dust. Our model suggests that the different spectral and polarization responses of the regolith are caused by changes in the size and amount of the small dark troilite particles. Based on the amount of troilite in the regolith model, we propose that CM-meteorites are the preferable meteorite analogue for Phaethon.

astro-ph.EP↗