地球与行星天体物理
Time-series photometry at mid-infrared wavelengths is becoming a common technique to search for atmospheres around rocky exoplanets. This method constrains the brightness temperature of the planet to determine whether heat redistribution is…
Context. Observations with warm Spitzer and JWST revealed high and variable brightness in the planet 55 Cnc e. Aims. Inventory of the tidal effects on the rotational and orbital evolution of the planet 55 Cnc e enhanced by the nonzero…
The origin of planetesimals ($\sim$100 km planet building blocks) has confounded astronomers for decades, as numerous growth barriers appear to impede their formation. In a recent paper we proposed a novel interaction where the streaming…
The interstellar object population of the Milky Way is a product of its stars. However, what is in fact a complex structure in the Solar neighbourhood has traditionally in ISO studies been described as smoothly distributed. Using a debiased…
WASP-107b is a warm (~740 K) transiting planet with a Neptune-like mass of ~30.5 Earth masses and Jupiter-like radius of ~0.94 Jupiter radius, whose extended atmosphere is eroding. Previous observations showed evidence for water vapour and…
Identifying Earth-like planets outside out solar system is a leading research goal in astronomy, but determining if candidate planets have atmospheres, and more importantly if they can retain atmospheres, is still out of reach. In this…
Photoevaporative models predict that the lower edge of the Neptune desert is sculpted by atmospheric mass loss. However, the stellar high energy fluxes that power hydrodynamic escape and set predicted mass loss rates can be uncertain by…
The unambiguous detection of magnetic star-planet interaction (SPI) via radio observations would provide a novel method for detecting exoplanets and probing their magnetic fields. Although direct radio detection of sub-Jovian planets is…
We present medium-wave ($\sim$0.5~$\mu$m to $\sim$13~$\mu$m) radiative flux distributions and spectra derived from high-resolution atmospheric dynamics simulations of an exoplanet \WASPP. This planet serves to illustrate several important…
Sub-Neptunes are the most common type of planet in our galaxy. Interior structure models suggest that the coldest sub-Neptunes could host liquid water oceans underneath their hydrogen envelopes -- sometimes called ``hycean'' planets. JWST…
We study the amount, size distribution and material composition of (sub-)mic aerosol particles in the lower Venus atmosphere < 50 km. Our GGchem phase-equilibrium model predicts metal-chloride and metal-fluoride molecules to be present in…
Luminosities of pre-main sequence stars evolve during the protoplanetary disc lifetime. This has a significant impact on the heating of their surrounding protoplanetary disks, the natal environments of planets. Moreover, stars of different…
We report photometric observations of Comet 103P/Hartley 2 during its 2023 apparition. Our campaign, conducted from August through December 2023, combined data from a global network of citizen astronomers coordinated by Unistellar and the…
Aerosols appear to be ubiquitous in exoplanetary atmospheres. However because our understanding of the physical processes that govern aerosols is incomplete, their presence makes the measurement of atmospheric properties, such as molecular…
The connection between the atmospheric composition of giant planets and their origin remains elusive. In this study, we explore how convective mixing can link the primordial planetary state to its atmospheric composition. We simulate the…
In the incremental growth model, planetesimal formation constitutes the least understood step in the process of planetary formation. The two main difficulties in this regard are the collision/fragmentation and the drift barriers. Numerous…
During Juno's only flyby of Europa, the Jupiter Energetic Particle Detector Instrument (JEDI) measured complex dropouts in the energetic ion flux in Europa's wake. We investigate the causes of these dropouts, focusing specifically on…
We present the first dataset of collisional (de)-excitation rate coefficients of HCN induced by CO, one of the main perturbing gases in cometary atmospheres. The dataset spans the temperature range of 5-50 K. It includes both state-to-state…
Climate change is inducing a global atmospheric contraction above the tropopause (~10 km), leading to systematic decrease in neutral air density. The impact of climate change on small meteoroids has already been observed over the last two…
Context. The most prominent cases of young star variability are accretion outbursts in FU Ori-type systems. The high power of such outbursts causes dramatic changes in the physical and chemical structure of a surrounding protoplanetary…