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Wolf 359
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Made famous by Star Trek: The Next Generation's fictional "Battle of Wolf 359", at 7.8 light-years distance Wolf 359 is the third nearest neighbour to humanity's home Solar System. This single young slow-burning star is far too dim for the unassisted human to see from Earth, but this star will live for around a hundred times longer than our own Sun.
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CN Leonis
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Title: A coronal explosion on the flare star CN Leonis
Authors: J.H.M.M. Schmitt, F. Reale, C. Liefke, U. Wolter, B. Fuhrmeister, A. Reiners, G. Peres

We present simultaneous high-temporal and high-spectral resolution observations at optical and soft X-ray wavelengths of the nearby flare star CN Leo. During our observing campaign a major flare occurred, raising the star's instantaneous energy output by almost three orders of magnitude. The flare shows the often observed impulsive behaviour, with a rapid rise and slow decay in the optical and a broad soft X-ray maximum about 200 seconds after the optical flare peak. However, in addition to this usually encountered flare phenomenology we find an extremely short (~2 sec) soft X-ray peak, which is very likely of thermal, rather than non-thermal nature and temporally coincides with the optical flare peak. While at hard X-ray energies non-thermal bursts are routinely observed on the Sun at flare onset, thermal soft X-ray bursts on time scales of seconds have never been observed in a solar nor stellar context. Time-dependent, one-dimensional hydrodynamic modelling of this event requires an extremely short energy deposition time scale of a few seconds to reconcile theory with observations, thus suggesting that we are witnessing the results of a coronal explosion on CN Leo. Thus the flare on CN Leo provides the opportunity to observationally study the physics of the long-sought "micro-flares" thought to be responsible for coronal heating.

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Date:
Wolf359
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Wolf 359 is a northern hemisphere star, located 7.78 light years from Earth, in the constellation Leo, the Lion.
It is only 1/100th the brightness of the Sun, and has a temperature of only 2,430 Kelvin
Like Barnard's Star, Wolf 359 is a (M6 V) red dwarf, with an age that is less than 10 billion years old.
Wolf 359 is also a Flare Star (that has been designated with the variable star name CN Leonis) and so can brighten dramatically from time to time.
The Hubble Space Telescope has produced images of Wolf 359 with unprecedented resolution to search for companions (planets or brown dwarfs).
Previous searches using ground-based, photographic astrometry and infrared speckle methods had already failed to find a large orbiting body at greater distances from the star.

Right ascension 10h 56m 29.2s Declination +07 00' 53"
Apparent magnitude (V) 13.53

Nearby stars from the LSPM-north Proper Motion Catalogue

Solar neighbourhood

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