Topic
Escape velocity
About: Escape velocity is a research topic. Over the lifetime, 961 publications have been published within this topic receiving 31907 citations. The topic is also known as: cosmic velocity.
Papers published on a yearly basis
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Papers
TL;DR: High-precision, high-cadence photometric measurements of the star HD 209458 are reported, which is known from radial velocity measurements to have a planetary-mass companion in a close orbit and the detailed shape of the transit curve due to both the limb darkening of thestar and the finite size of the planet is clearly evident.
Abstract: We report high-precision, high-cadence photometric measurements of the star HD 209458, which is known from radial velocity measurements to have a planetary-mass companion in a close orbit. We detect two separate transit events at times that are consistent with the radial velocity measurements. In both cases, the detailed shape of the transit curve due to both the limb darkening of the star and the finite size of the planet is clearly evident. Assuming stellar parameters of 1.1 R⊙ and 1.1 M⊙, we find that the data are best interpreted as a gas giant with a radius of 1.27 ± 0.02 RJup in an orbit with an inclination of 871 ± 02. We present values for the planetary surface gravity, escape velocity, and average density and discuss the numerous observations that are warranted now that a planet is known to transit the disk of its parent star.
1,494 citations
TL;DR: In this article, high precision, high cadence photometric measurements of the star HD 209458 are reported, which is known from radial velocity measurements to have a planetary mass companion in a close orbit.
Abstract: We report high precision, high cadence photometric measurements of the star HD 209458, which is known from radial velocity measurements to have a planetary mass companion in a close orbit. We detect two separate transit events at times that are consistent with the radial velocity measurements. In both cases, the detailed shape of the transit curve due to both the limb darkening of the star and the finite size of the planet is clearly evident. Assuming stellar parameters of 1.1 R_Sun and 1.1 M_Sun, we find that the data are best interpreted as a gas giant with a radius of 1.27 +/- 0.02 R_Jup in an orbit with an inclination of 87.1 +/- 0.2 degrees. We present values for the planetary surface gravity, escape velocity, and average density, and discuss the numerous observations that are warranted now that a planet is known to transit the disk of its parent star.
1,480 citations
TL;DR: In this article, a mean pulsar birth velocities of 450 ± 90 km s−1 have been derived, which exceeds the escape velocity from binary systems, globular clusters and the Galaxy and so will affect our understanding of the retention of neutron stars in these systems.
Abstract: NEUTRON stars are usually born during the supernova explosion of a massive star. Any small asymmetry during the explosion can result in a substantial ‘kick’ velocity1 to the neutron star. Pulsars (rapidly rotating, magnetized neutron stars) have long been known to have high space velocities2,3, but new measurements of proper motion4–6, adoption of a new distance scale for the pulsars7 and the realization that some previous velocities were systematically low by a factor of 2 (ref. 8) have prompted us to reassess these velocities. Here, taking into account a strong selection effect that makes the observed velocities unrepresentative of those acquired at birth9, we arrive at a mean pulsar birth velocity of 450 ± 90 km s–1 This exceeds the escape velocity from binary systems, globular clusters and the Galaxy, and so will affect our understanding of the retention of neutron stars in these systems. Those neutron stars that are retained by the Milky Way will be distributed more isotropically than has been thought10–12, which may result in a distribution like that of the γ-ray burst sources.
875 citations
Kapteyn Astronomical Institute1, Johns Hopkins University2, Mount Stromlo Observatory3, University of Victoria4, University of Cambridge5, University of Oxford6, University of Leicester7, University of Central Lancashire8, University of Basel9, INAF10, Macquarie University11, University of Ljubljana12
TL;DR: In this paper, the authors used cosmological simulations of disc galaxy formation to motivate their assumptions on the shape of the velocity distribution, allowing for a significantly more precise measurement of the escape velocity compared to previous studies.
Abstract: We report new constraints on the local escape speed of our Galaxy. Our analysis is based on a sample of high-velocity stars from the RAVE survey and two previously published data sets. We use cosmological simulations of disc galaxy formation to motivate our assumptions on the shape of the velocity distribution, allowing for a significantly more precise measurement of the escape velocity compared to previous studies. We find that the escape velocity lies within the range 498
730 citations
TL;DR: In this article, a comprehensive theory for the region of a planetary atmosphere where collisions are rare and where the controlling factors are gravitational attraction and thermal energy conducted from below is presented, where different types of particle orbits are treated separately; coronal particles are either ballistic (meaning captive particles whose orbits intersect the critical level), satellite (captive particles orbiting above the critical levels), or escaping.
552 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2022 | 1 |
| 2021 | 41 |
| 2020 | 39 |
| 2019 | 41 |
| 2018 | 48 |
| 2017 | 37 |