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The X-Ray Sun in Time: A Study of the Long-Term Evolution of Coronae of Solar-Type Stars
We have used the ASCA and ROSAT X-ray satellites to probe the coronae of a sample of nine solar-like G stars. These stars are all ostensibly single with ages ranging from 70 Myr to 9 Gyr and have
X-ray astronomy of stellar coronae
Abstract.X-ray emission from stars in the cool half of the Hertzsprung-Russell diagram is generally attributed to the presence of a magnetic corona that contains plasma at temperatures exceeding 1
The PLATO 2.0 mission
PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses
The Sun in Time: Activity and Environment
The Sun’s magnetic activity has steadily declined during its main-sequence life. While the solar photospheric luminosity was about 30% lower 4.6 Gyr ago when the Sun arrived on the main sequence
Extreme Ultraviolet Explorer Deep Survey observations of cool stars (spectral type F to M) have been used to investigate the distribution of coronal —are rates in energy and its relation to activity
X-ray spectroscopy of stars
Non-degenerate stars of essentially all spectral classes are soft X-ray sources. Their X-ray spectra have been important in constraining physical processes that heat plasma in stellar environments to
Million-Degree Plasma Pervading the Extended Orion Nebula
X-ray observations obtained with the X-ray Multi-Mirror satellite XMM-Newton reveal that a hot plasma with a temperature of 1.7 to 2.1 million kelvin pervades the southwest extension of the nebula, suggesting that this x-ray outflow phenomenon must be widespread throughout the authors' Galaxy.
Physical Processes in Magnetically Driven Flares on the Sun, Stars, and Young Stellar Objects
The first flare on the Sun was observed exactly 150 years ago. During most of the long history, only secondary effects have been noticed, so flares remained a riddle. Now the primary flare products,
The sun, solar analogs and the climate
The Earth's Climate and Its Response to Solar Variability.- Solar Outputs, Their Variations and Their Effects on Earth.- Stellar Analogs of Solar Activity: The Sun in A Stellar Context.
Wind clumping and the wind-wind collision zone in the Wolf-Rayet binary gamma ² Velorum observations at high and low state. XMM-Newton observations at high and low state
We present XMM-Newton observations of γ 2 Velorum (WR 11, WC8+O7.5III, P = 78.53 d), a nearby Wolf-Rayet binary system, at its X-ray high and low states. At high state, emission from a hot