What is the closest star to the sun
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Closest Star to the Sun: Proxima Centauri
Proxima Centauri: The Nearest Stellar Neighbor
The closest star to the Sun is Proxima Centauri, a red dwarf located approximately 1.295 parsecs (4.24 light-years) away from us2 10. Proxima Centauri is part of the Alpha Centauri star system, which also includes Alpha Centauri A and Alpha Centauri B. Despite its proximity, Proxima Centauri is much smaller and cooler than the Sun, with an effective temperature of around 3,050 Kelvin and a luminosity that is only 0.15% of the Sun's10.
Characteristics of Proxima Centauri
Proxima Centauri is a low-mass star with about 12% of the Sun's mass and a radius that is 14% of the Sun's radius10. It is considered a moderately active star, exhibiting stellar flares that can significantly affect its surrounding environment. The star's rotation period is approximately 83 days, and its quiescent activity levels and X-ray luminosity are comparable to those of the Sun10.
Proxima Centauri's Planetary System
Proxima Centauri hosts at least one known exoplanet, Proxima b, which is of particular interest due to its potential habitability. Proxima b has a minimum mass of about 1.3 Earth masses and orbits the star at a distance of approximately 0.05 astronomical units (AU) with a period of around 11.2 days10. This places Proxima b within the habitable zone of its star, where conditions might allow for the presence of liquid water on its surface.
Other Close Stellar Encounters
While Proxima Centauri is the closest star to the Sun, other stars have had or will have close encounters with our solar system. For instance, the K7 dwarf star Gliese 710 is predicted to pass within 0.0636 parsecs (13,000 AU) of the Sun in about 1.3 million years1 7 9. This close approach could potentially disturb the Oort Cloud, leading to an increase in cometary activity in the inner solar system1 9.
Conclusion
Proxima Centauri remains the closest known star to the Sun, situated just over four light-years away. Its planetary system, particularly the potentially habitable exoplanet Proxima b, continues to be a focal point of astronomical research. Additionally, future close encounters with stars like Gliese 710 highlight the dynamic nature of our galactic neighborhood and its potential impact on the solar system.
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Most relevant research papers on this topic
Stars That Approach within One Parsec of the Sun: New and More Accurate Encounters Identified in Gaia Data Release 3
Gaia DR3 improves our understanding of close encounters between stars and the Sun, potentially impacting life on Earth through gravitational perturbations and ionizing radiation.
THE SOLAR NEIGHBORHOOD. XXVI. AP Col: THE CLOSEST (8.4 pc) PRE-MAIN-SEQUENCE STAR
AP Col is the nearest pre-main-sequence star, 8.4 pc from the Sun, and likely a member of the 40 Myr old Argus/IC 2391 Association.
The Sun and Stars
The sun, being the nearest star, is relatively close to us, and we can learn more about its detailed structure than about other stars.
New stellar encounters discovered in the second Gaia data release
The second Gaia data release reveals 694 stars with potential close encounters to the Sun within 15 Myr, with 26 having a 50% chance of coming closer than 1 pc.
A star passing close to the solar system.
Gliese 710, a small faint star, will pass within the Oort Cloud in 1.3 million years, potentially generating large numbers of new comets.
A terrestrial planet candidate in a temperate orbit around Proxima Centauri
A small planet with a minimum mass of 1.3 Earth masses orbiting Proxima Centauri has been discovered, with its equilibrium temperature within the range where water could be liquid on its surface.
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