Fast-evolving weather for the coolest of our two new substellar neighbours

Abstract

We present the results of an intense photometric monitoring in the near-infrared (~0.9 microns) with the TRAPPIST robotic telescope of the newly discovered binary brown dwarf WISE J104915.57-531906.1, the third closest system to the Sun at a distance of only 2 pc. Our twelve nights of photometric time-series reveal a quasi-periodic (P = 4.87+-0.01 h) variability with a maximal peak-peak amplitude of ~11% and strong night-to-night evolution. We attribute this variability to the rotational modulation of fast-evolving weather patterns in the atmosphere of the coolest component (~T1-type) of the binary, in agreement with the cloud fragmentation mechanism proposed to drive the spectroscopic morphologies of brown dwarfs at the L/T transition. No periodic signal is detected for the hottest component (~L8-type). For both brown dwarfs, our data allow us to firmly discard any unique transit during our observations for planets >= 2 Rearth. For orbital periods smaller than ~9.5 h, transiting planets are excluded down to an Earth-size.

4 pages, 4 figures. Submitted as Letter to A&A. Second version shortened to match the format of A&A Letters, with a few minor modifications

References in corpus (8)

• The Evolution of L and T Dwarfs in Color-Magnitude Diagrams
• The 0.8-14.5 micron Spectra of Mid-L to Mid-T Dwarfs: Diagnostics of Effective Temperature, Grain Sedimentation, Gas Transport, and Surface Gravity
• HST Spectral Mapping of L/T Transition Brown Dwarfs Reveals Cloud Thickness Variations
• Discovery of a Binary Brown Dwarf at 2 Parsecs from the Sun
• Near Infrared Monitoring of Ultracool Dwarfs: Prospects for Searching for Transiting Companions
• Characterization of the Nearby L/T Binary Brown Dwarf WISE J104915.57-531906.1 at 2 Parsecs from the Sun
• A Search for Photometric Variability in L and T type Brown Dwarf Atmospheres
• Habitable Planets Eclipsing Brown Dwarfs: Strategies for Detection and Characterization

Cited by in corpus (78)

• Weather on Other Worlds. II. Survey Results: Spots Are Ubiquitous on L and T Dwarfs
• Population Properties of Brown Dwarf Analogs to Exoplanets
• On the Cool Side: Modeling the Atmospheres of Brown Dwarfs and Giant Planets
• A global cloud map of the nearest known brown dwarf
• Strong Brightness Variations Signal Cloudy-to-Clear Transition of Brown Dwarfs
• Brown Dwarf Photospheres are Patchy: A Hubble Space Telescope Near-infrared Spectroscopic Survey Finds Frequent Low-level Variability
• Aerosols in Exoplanet Atmospheres
• WASP-80b has a dayside within the T-dwarf range
• The Viewing Geometry of Brown Dwarfs Influences Their Observed Colours and Variability Properties
• Doppler Imaging of Exoplanets and Brown Dwarfs
• $ExtrasolarStorms$: Pressure-dependent Changes In Light Curve Phase In Brown Dwarfs From Simultaneous $Hubble$ and $Spitzer$ Observations
• Weather on the Nearest Brown Dwarfs: Resolved Simultaneous Multi-Wavelength Variability Monitoring of WISE J104915.57-531906.1AB
• Atmospheres of Brown Dwarfs
• An independent analysis of the brown dwarf atmosphere monitoring (BAM) data: large-amplitude variability is rare outside the L/T transition
• High-Cadence, High-Contrast Imaging for Exoplanet Mapping: Observations of the HR 8799 Planets with VLT/SPHERE Satellite Spot-Corrected Relative Photometry
• Spectral Variability from the Patchy Atmospheres of T and Y Dwarfs
• Temperature Fluctuations as a Source of Brown Dwarf Variability
• Variability in a Young, L/T Transition Planetary-Mass Object
• Atmospheric circulation of brown dwarfs and directly imaged exoplanets driven by cloud radiative feedback: global and equatorial dynamics
• Cloud structure of the nearest brown dwarfs: Spectroscopic variability of Luhman 16AB from the Hubble Space Telescope
• Spitzer Variability Properties of Low-Gravity L Dwarfs
• Weather on Other Worlds. V. The Three Most Rapidly Rotating Ultra-Cool Dwarfs
• HST Rotational Spectral Mapping of Two L-Type Brown Dwarfs: Variability In and Out of Water Bands Indicates High-Altitude Haze Layers
• Signatures of Cloud, Temperature, and Gravity From Spectra of the Closest Brown Dwarfs
• The First Detection of Photometric Variability in a Y Dwarf: WISE J140518.39+553421.3
• Atmospheric variability driven by radiative cloud feedback in brown dwarfs and directly imaged extrasolar giant planets
• Strong Near-Infrared Spectral Variability of the Young Cloudy L Dwarf Companion VHS J1256-1257 b
• A Monitoring Campaign for Luhman 16AB. I. Detection of Resolved Near-Infrared Spectroscopic Variability
• First limits on the occurrence rate of short-period planets orbiting brown dwarfs
• TESS Observations of the Luhman 16AB Brown Dwarf System: Rotational Periods, Lightcurve Evolution, and Zonal Circulation
• Maps of Evolving Cloud Structures in Luhman 16AB from HST Time-Resolved Spectroscopy
• Cloud Structure of the Nearest Brown Dwarfs II: High-amplitude variability for Luhman 16 A and B in and out of the 0.99 micron FeH feature
• Neptune's Dynamic Atmosphere from Kepler K2 Observations: Implications for Brown Dwarf Light Curve Analyses
• The JWST Weather Report from the Nearest Brown Dwarfs I: multi-period JWST NIRSpec + MIRI monitoring of the benchmark binary brown dwarf WISE 1049AB
• Colour-magnitude diagrams of transiting Exoplanets - II. A larger sample from photometric distances
• Cloud Atlas: Discovery of Rotational Spectral Modulations in a Low-mass, L-type Brown Dwarf Companion to a Star
• One more neighbor: The first brown dwarf in the VVV survey
• Ionisation in atmospheres of brown dwarfs and extrasolar planets VI: Properties of large-scale discharge events
• Lightning climatology of exoplanets and brown dwarfs guided by Solar System data
• Near-infrared transmission spectrum of TRAPPIST-1 h using Hubble WFC3 G141 observations
• Detection of new strongly variable brown dwarfs in the L/T transition
• Rotational spectral modulation of cloudless atmospheres for L/T Brown Dwarfs and Extrasolar Giant Planets
• Possible astrometric discovery of a substellar companion to the closest binary brown dwarf system WISE J104915.57-531906.1
• Individual, Model-Independent Masses of the Closest Known Brown Dwarf Binary to the Sun
• Weather on Other Worlds. III. A Survey for T Dwarfs with High Amplitude Optical Variability
• Rotation periods and photometric variability of rapidly rotating ultra-cool dwarfs
• Weather on Other Worlds. IV. H$\alpha$ emission and photometric variability are not correlated in L0$-$T8 dwarfs
• Hubble Space Telescope astrometry of the closest brown dwarf binary system -- I. Overview and improved orbit
• VLT X-shooter spectroscopy of the nearest brown dwarf binary
• Kepler Monitoring of an L Dwarf II. Clouds with Multiyear Lifetimes
• SPECULOOS exoplanet search and its prototype on TRAPPIST
• Mass ratio of the 2 pc binary brown dwarf LUH16 and limits on planetary companions from astrometry
• A search for photometric variability in the young T3.5 planetary-mass companion GU Psc b
• Spitzer Light Curves of the Young, Planetary-Mass TW Hya Members 2MASS J11193254-1137466AB and WISEA J114724.10-204021.3
• On the Correlation between L Dwarf Optical and Infrared Variability and Radio Aurorae
• The Deepest Constraints on Radio and X-ray Magnetic Activity in Ultracool Dwarfs from WISE J104915.57-531906.1
• Cloud-convection feedback in brown dwarfs atmosphere
• A Late-type L Dwarf at 11 pc Hiding in the Galactic Plane Characterized Using Gaia DR2
• Global weather map reveals persistent top-of-atmosphere features on the nearest brown dwarfs
• Rotation periods and astrometric motions of the Luhman 16AB brown dwarfs by high-resolution lucky-imaging monitoring
• Characterizing The Cloud Decks of Luhman 16AB with Medium-Resolution Spectroscopic Monitoring
• Spitzer Space Telescope Mid-IR Light Curves of Neptune
• Design Considerations for a Ground-Based Search for Transiting Planets around L and T Dwarfs
• Spectral Variability of Two Rapidly Rotating Brown Dwarfs: 2MASS J08354256-0819237 and 2MASS J18212815+1414010
• EXONEST: The Bayesian Exoplanetary Explorer
• Exploring the directly imaged HD 1160 system through spectroscopic characterization and high-cadence variability monitoring
• The Perkins INfrared Exosatellite Survey (PINES) II. Transit Candidates and Implications for Planet Occurrence around L and T Dwarfs
• A Unified Spectroscopic and Photometric Model to Infer Surface Inhomogeneity: Application to Luhman 16B
• Prospects for detecting the Rossiter-McLaughlin effect of Earth-like planets: the test case of TRAPPIST-1b and c
• HST astrometry of the closest Brown Dwarfs -- II. Improved parameters and constraints on a third body
• Science Case and Requirements for the MOSAIC Concept for a Multi-Object Spectrograph for the European Extremely Large Telescope
• Flash ionisation signature in coherent cyclotron emission from Brown Dwarfs
• Exoplanet Atmosphere Measurements from Direct Imaging
• Weather on Other Worlds. VI. Optical Spectrophotometry of Luhman 16B Reveals Large-amplitude Variations in the Alkali Lines
• A 1.48-2.48 $\mu$m R=28000 spectroscopic atlas of the L7.5 and T0.5 components of the nearest pair of brown dwarfs: Luhman 16AB
• Optical Variability, Rotation Period and Inclination Angle of the M9.5 dwarf BRI 0021-0214
• Disentangling the Signatures of Blended-Light Atmospheres in L/T Transition Brown Dwarfs
• The Perkins INfrared Exosatellite Survey (PINES) I. Survey Overview, Reduction Pipeline, and Early Results