Data from: A Saturn-mass free-floating-planet event
Data files
Jan 01, 2026 version files 6.30 MB
-
Gaia-FoVF_G.csv
1.10 KB
-
Gaia-FoVP_G.csv
1.07 KB
-
gett.py
1.95 KB
-
KMTA02_I.csv
456.56 KB
-
KMTA42_I.csv
464.96 KB
-
KMTS02_I.csv
498.47 KB
-
KMTS42_I.csv
525.53 KB
-
MIKE.fits
3.91 MB
-
OGLE_I.csv
433.23 KB
-
README.md
1.95 KB
Abstract
A population of free-floating planets is known from gravitational microlensing surveys. None of those planets have a directly measured mass, due to a degeneracy with the distance, though the population statistics indicate that many are less massive than Jupiter. We report a microlensing event, KMT-2024-BLG-0792/OGLE-2024-BLG-0516, which was observed from both ground- and space-based telescopes. This breaks the mass-distance degeneracy; we determine that the event was caused by a planet with 0.219+0.075-0.046 Jupiter masses, which is either gravitationally unbound or on a very wide orbit. By comparing to the statistical properties of other observed microlensing events and predictions from simulations, we infer that this object likely formed in a protoplanetary disk, not in isolation like a brown dwarf. Dynamical processes then ejected it from its birth place, producing a free-floating object.
Dataset DOI: 10.5061/dryad.g79cnp622
Description of the data and file structure
gett.py, gett version 1.0, a code used to model the terrestrial microlens parallax and diurnal microlens parallax effects.
MIKE.fits, in the standard Flexible Image Transport System (FITS) format for spectroscopic data, is the MIKE spectroscopic data product of KMT-2024-BLG-0792/OGLE-2024-BLG-0516 used in the spectral analysis.
The photometric data files for all sites used in the microlensing light-curve modeling of KMT-2024-BLG-0792/OGLE-2024-BLG-0516 are provided in .csv format. Each file contains three columns: mid-exposure time ("BJD_TCB"), given in Barycentric Julian Date (BJD) with Barycentric Coordinate Time (TCB); magnitude ("Mag"); and error bar ("Err"). When performing the light-curve modeling, error bars are re-normalized as described in the "Microlensing analysis" section of "Materials and Methods". The error bars provided in each file should be multiplied by a scaling factor, which is given in the "escale" column of the following table. The table also includes the filename ("filename"), the site description ("site"), and the filter used ("filter") for each dataset.
| filename | site | filter | escale |
|---|---|---|---|
| OGLE_I.csv | OGLE | I | 2.49 |
| KMTS02_I.csv | KMTNet, South Africa, BLG02 field | I | 1.71 |
| KMTS42_I.csv | KMTNet, South Africa, BLG42 field | I | 1.84 |
| KMTA02_I.csv | KMTNet, Australia, BLG02 field | I | 1.85 |
| KMTA42_I.csv | KMTNet, Australia, BLG42 field | I | 1.74 |
| Gaia-FoVF_G.csv | Gaia, FoVF | G | 1.54 |
| Gaia-FoVP_G.csv | Gaia, FoVP | G | 1.54 |