Eric Lopez
A5037229350- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Space Exploration and Technology
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Planetary Science and Exploration
- Astronomical and nuclear sciences
- Scientific Research and Discoveries
- Spacecraft and Cryogenic Technologies
- High-pressure geophysics and materials
- History and Developments in Astronomy
- Calibration and Measurement Techniques
- Adaptive optics and wavefront sensing
- Space Science and Extraterrestrial Life
- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Methane Hydrates and Related Phenomena
- Earthquake Detection and Analysis
- Isotope Analysis in Ecology
- Solar and Space Plasma Dynamics
- Ocular and Laser Science Research
- Hydrocarbon exploration and reservoir analysis
- GNSS positioning and interference
Royal Observatory
2015-2024
University of Edinburgh
2015-2024
Goddard Space Flight Center
2017-2024
Deleted Institution
2018-2020
NASA Exoplanet Science Institute
2020
Max Planck Society
2018
National Polytechnic School
2018
UK Astronomy Technology Centre
2016-2017
University of California, Santa Cruz
2011-2015
Observatoire de Paris
2008
Transiting planet surveys like Kepler have provided a wealth of information on the distribution planetary radii, particularly for new populations super-Earth and sub-Neptune sized planets. In order to aid in physical interpretation these we compute model radii low-mass rocky planets with hydrogen-helium envelopes. We provide 1-20 Earth masses, envelope fractions from 0.01-20%, levels irradiation 0.1-1000x Earth's, ages 100 Myr 10 Gyr. addition simple analytic fits that summarize how radius...
We use models of coupled thermal evolution and photo-evaporative mass loss to understand the formation Kepler-36 system. show that large contrast in mean planetary density observed by Carter et al. can be explained as a natural consequence photo-evaporation from planets formed with similar initial compositions. However, rather than being due differences XUV irradiation between planets, we find this is difference masses planets' rock/iron cores impact has on mass-loss evolution. explore...
We use models of thermal evolution and extreme ultraviolet (XUV) driven mass loss to explore the composition history low-mass, low-density transiting planets. investigate Kepler-11 system in detail provide estimates both current past planetary compositions. find that an H/He envelope on Kepler-11b is highly vulnerable loss. By comparing formation models, we show situ extremely difficult. Instead propose it a water-rich sub-Neptunes migrated from beyond snow line. For broader population...
In the Solar system planets' compositions vary with orbital distance, rocky planets in close orbits and lower-density gas giants wider orbits. The detection of close-in giant around other stars was first clue that this pattern is not universal, can change substantially after their formation. Here we report another violation orbit-composition pattern: two orbiting same star distances differing by only 10%, densities a factor 8. One planet likely `super-Earth', whereas more akin to Neptune....
We present the detection of five planets -- Kepler-62b, c, d, e, and f size 1.31, 0.54, 1.95, 1.61 1.41 Earth radii, orbiting a K2V star at periods 5.7, 12.4, 18.2, 122.4 267.3 days, respectively. The outermost (Kepler-62e & -62f) are super-Earth-size (1.25 < planet radius/earth radius 2.0) in habitable zone (HZ) their host star, receiving 1.2 +- 0.2 0.41 0.05 times solar flux Earth's orbit. Theoretical models Kepler-62e -62f for stellar age ~7 Gyr suggest that both could be solid: either...
The Kepler Mission has found thousands of planetary candidates with radii between 1 and 4 . These planets have no analogues in our own solar system, providing an unprecedented opportunity to understand the range distribution compositions allowed by planet formation evolution. A precise mass measurement is usually required constrain possible composition individual super-Earth-sized planet, but these measurements are difficult expensive make for majority (PCs). Fortunately, adopting a...
Exoplanet discoveries of recent years have provided a great deal new data for studying the bulk compositions giant planets. Here we identify 47 transiting planets ($20 M_\oplus < M 20 M_{\mathrm{J}}$) whose stellar insolation is low enough ($F_* 2\times10^8\; \text{erg}\; \text{s}^{-1}\; \text{cm}^{-2}$, or roughly $T_\text{eff} 1000$) that they are not affected by hot Jupiter radius inflation mechanism(s). We compute set thermal and structural evolution models use these in comparison with...
We show that photoevaporation of small gaseous exoplanets (“mini-Neptunes”) in the habitable zones M dwarfs can remove several Earth masses hydrogen and helium from these planets transform them into potentially worlds. couple X-ray/extreme ultraviolet (XUV)–driven escape, thermal evolution, tidal orbital migration to explore types systems may harbor such “habitable evaporated cores” (HECs). find HECs are most likely form with ∼1 M⊕ solid cores up about 50% H/He by mass, though whether or not...
Recent surveys have uncovered an exciting new population of ultra-short-period (USP) planets with orbital periods less than a day. These typically radii <1.5 Earth radii, indicating that they likely rocky compositions. This stands in contrast to the overall distribution out ~100 days, which is dominated by low-density sub-Neptunes above 2 must gaseous envelopes explain their size. However, on orbits, are bombarded intense levels photo-ionizing radiation and consequently extremely vulnerable...
The Kepler-11 planetary system contains six transiting planets ranging in size from 1.8 to 4.2 times the radius of Earth. Five these orbit a tightly packed configuration with periods between 10 and 47 days. We perform dynamical analysis based upon transit timing variations observed more than three years Kepler photometric data. Stellar parameters are derived using combination spectral classification constraints on star's density profiles together eccentricity vectors provided by our study....
Ultra-short period (USP) planets are a class of low mass with periods shorter than one day. Their origin is still unknown, photo-evaporation mini-Neptunes and in-situ formation being the most credited hypotheses. Formation scenarios differ radically in predicted composition USP planets, it therefore extremely important to increase limited sample precise accurate density measurements. We report here characterization an planet 0.28 days around K2-141 (EPIC 246393474), validation outer 7.7...
One of the most significant advances by NASA's Kepler Mission was discovery an abundant new population highly irradiated planets with sizes between those Earth and Neptune, unlike anything found in Solar System. Subsequent analysis showed that at ∼1.5 R⊕ there is a transition from predominantly rocky super-Earths to non-rocky sub-Neptunes, which must have substantial volatile envelopes explain their low densities. Determining origin these will be critical our understanding low-mass planet...
We present here the detection of a system four low-mass planets around bright (V=5.5) and close-by (6.5 pc) star HD219134. This is first result Rocky Planet Search program with HARPS-N on TNG in La Palma. The inner planet orbits 3.0937 +/-0.0004 days, quasi-circular orbit semi-major axis 0.0382 +/- 0.0003 AU. Spitzer observations allowed us to detect transit front making HD219134b nearest known transiting date. From amplitude radial-velocity variation (2.33 0.24 m/s) observed depth (359 38...
A correlation between giant-planet mass and atmospheric heavy elemental abundance was first noted in the past century from observations of planets our own Solar System, has served as a cornerstone planet formation theory. Using data Hubble Spitzer Space Telescopes 0.5 to 5 microns, we conducted detailed study transiting Neptune-mass exoplanet HAT-P-26b. We detected prominent H2O absorption bands with maximum base-to-peak amplitude 525ppm transmission spectrum. water proxy for metallicity,...
NASA's Kepler Mission has revealed two transiting planets orbiting Kepler-68. Follow-up Doppler measurements have established the mass of innermost planet and a third jovian-mass beyond planets. Kepler-68b, in 5.4 day orbit 8.3 +/- 2.3 Earth, radius 2.31 0.07 Earth radii, density 3.32 0.92 (cgs), giving Kepler-68b intermediate between that ice giants Earth. Kepler-68c is Earth-sized with 0.953 transits on 9.6 orbit; validation posed unique challenges. Kepler-68d an orbital period 580 15 days...
Abstract We present the discovery and validation of a three-planet system orbiting nearby (31.1 pc) M2 dwarf star TOI-700 (TIC 150428135). lies in TESS continuous viewing zone Southern Ecliptic Hemisphere; observations spanning 11 sectors reveal three planets with radii ranging from 1 R ⊕ to 2.6 orbital periods 9.98 37.43 days. Ground-based follow-up combined diagnostic vetting tests enables us rule out common astrophysical false-positive scenarios validate planets. The outermost planet, d,...
ABSTRACT Since the discovery of first transiting hot Jupiters, models have sought to explain anomalously large radii highly irradiated gas giants. We now know that size Jupiter radius anomalies scales strongly with a planet's level irradiation and numerous like tidal heating, ohmic dissipation, thermal tides since been developed help these inflated radii. In general, however, can be grouped into two broad categories: directly inflate planetary by depositing fraction incident interior simply...
ABSTRACT Strongly irradiated giant planets are observed to have radii larger than thermal evolution models predict. Although these inflated been known for over 15 years, it is unclear whether their inflation caused by the deposition of energy from host star or inhibited cooling planet. These processes can be distinguished if planet becomes highly only when evolves onto red branch. We report discovery K2-97b, a 1.31 ± 0.11 R J , 1.10 M orbiting 4.20 0.14 ⊙ 1.16 0.12 with an orbital period 8.4...
We present the confirmation of two new planets transiting nearby mid-M dwarf LTT 3780 (TIC 36724087, TOI-732, $V=13.07$, $K_s=8.204$, $R_s$=0.374 R$_{\odot}$, $M_s$=0.401 M$_{\odot}$, d=22 pc). The planet candidates are identified in a single TESS sector and validated with reconnaissance spectroscopy, ground-based photometric follow-up, high-resolution imaging. With measured orbital periods $P_b=0.77$ days, $P_c=12.25$ days sizes $r_{p,b}=1.33\pm 0.07$ R$_{\oplus}$, $r_{p,c}=2.30\pm 0.16$...
HD 179070, aka Kepler-21, is a V = 8.25 F6IV star and the brightest exoplanet host discovered by Kepler. An early detailed analysis Howell et al. (2012) of first thirteen months (Q0 - Q5) Kepler light curves revealed transits planetary companion, Kepler-21b, with radius about 1.60 +/- 0.04 R_earth an orbital period 2.7857 days. However, they could not determine mass planet from initial radial velocity observations Keck-HIRES, were only able to impose 2-sigma upper limit 10 M_earth. Here we...
Stellar multiplicity is believed to influence planetary formation and evolution, although the precise nature extent of this role remain ambiguous. We present a study aimed at testing stellar in and/or evolution most massive, close-in substellar companions. Using direct imaging observations, as well Gaia DR2 catalogue, we searched for wide binary companions 38 stars hosting massive giant planets or brown dwarfs (M > 7 MJup) on orbits shorter than ~1 AU. report discovery new component WASP-14...