Results 91 to 100 of about 9,166,032 (298)
, 2020 The population of exoplanetary systems detected by Kepler provides opportunities to refine our understanding of planet formation. Unraveling the conditions needed to produce the observed exoplanet systems will allow us to make informed predictions as to ...
Apai, Dániel +4 more
core +1 more source
A Paleoarchaean impact crater in the Pilbara Craton, Western Australia
Nature CommunicationsThe role of meteorite impacts in the origin, modification, and destruction of crust during the first two billion years of Earth history (4.5–2.5 billion years ago; Ga) is disputed.
Christopher L. Kirkland +6 more
doaj +1 more source
Interferometric view into RT Pav’s long secondary period
Astronomy & AstrophysicsContext. Long secondary periods (LSPs) occur in roughly one third of evolved stars, yet their origin remains uncertain. Two leading hypotheses are oscillatory convective modes and a binary companion enshrouded in dust. Aims. We investigate the LSP in the
Courtney-Barrer B. +8 more
doaj +1 more source
Fiber‐Format Flexible Linear Electrostatic Motors
Advanced Materials, EarlyView.A flexible coaxial fibre‐format electrostatic motor enables backdrivable and reversible linear actuation with high force density and functionality under bending, offering a scalable actuation platform for soft and wearable robotics. ABSTRACT Linear motion is fundamental to robotics, yet existing solutions are either rigid electromagnetic motors or ...
Sylvain Schaller, Herbert Shea
wiley +1 more source
International Astronomical Union Colloquium, 1999 AbstractThe past decade brought direct evidence of the previously surmised exoplanetary systems. A variety of planetary system types exist those around pulsars, around both young and old main-sequence stars (as evidenced by planetesimal disks of the Beta Pictoris-type), and the mature giant exoplanets found in radial velocity surveys.
openaire +1 more source
Phase‐Engineered MoS2 Quantum Monolayer Catalysts
Advanced Materials, EarlyView.A new type of catalyst model—phase‐engineered MoS2 quantum‐monolayer catalyst (∼0.8 nm thick, < 6 nm in the lateral size; switchable freely among metallic 1T, semiconducting 2H, and a hybrid phase of metallic‐semiconducting 1T‐2H)—is reported. It can efficiently and stably drive photochemical H2, syngas and ammonia synthesis as a catalyst or co ...
Ruijie Yang +12 more
wiley +1 more source
How a close-in planet protects its white dwarf host from pollution
Astronomy & AstrophysicsContext. Approximately 25-50% of the white dwarfs (WDs) exhibit metal absorption lines in their photospheres. The lines are attributed to accretion from their remnant planetary systems. Although WDs with detected planetary systems are more likely to show
Zhang Xin-Yue +3 more
doaj +1 more source
Advanced Materials Interfaces, EarlyView.By analyzing the thermal‐mechanical properties and molecular‐scale interactions in polyacrylamide (PAAM) hydrogels, this research demonstrates a rubber‐glass‐crystal phase transition under the combined stimuli of temperature and moisture. Because of these hybrid phase transitions, PAAM hydrogels exhibit shape memory behavior in thermal and moist ...
Shuai Xu +7 more
wiley +1 more source
Cold giant discoveries from a joint radial-velocity and astrometry framework
Astronomy & AstrophysicsContext. The population of long-period giant planets shapes planetary system architectures and formation pathways, but these cold Jupiters remain relatively unexplored.
Peña Pablo A. +13 more
doaj +1 more source
Exoplanets: Past, Present, and Future
Galaxies, 2018 Our understanding of extra-solar planet systems is highly driven by advances in observations in the past decade. Thanks to high precision spectrographs, we are able to reveal unseen companions to stars with the radial velocity method.
Chien-Hsiu Lee
doaj +1 more source