We present Extreme Ultraviolet Explorer spectroscopy and photometry of the nearby F8 V star HD 35850 ( HR 1817 ) .
The EUVE short-wavelength 75–175 Å and medium-wavelength 160–365 Å spectra reveal 28 emission lines from Fe IX and Fe XV to Fe XXIV .
The Fe XXI \lambda \lambda 102 , 129 ratio yields an upper limit for the coronal electron density , \log n _ { e } < 11.6 cm ^ { -3 } .
The EUVE SW spectrum shows a small but clearly detectable continuum .
The 75–150 Å line-to-continuum ratio indicates approximately solar Fe abundances , with 0.8 < Z < 1.6 ( 90 % confidence interval ) .
Upper limits have been derived for a dozen high-emissivity Fe X through Fe XIV lines .
The resulting EM distribution is characterized by two broad temperature components at \log T of 6.8 and 7.4 .
Over the course of the 1-week observation , large-amplitude , long-duration flares were not seen in the EUVE Deep Survey light curve , though the light curve does show signs of persistent , low-level flaring , and possible rotational modulation .

The EUVE spectra have been compared with non-simultaneous ASCA SIS spectra of HD 35850 obtained in 1995 .
The SPEX DEM analysis of the SIS spectrum indicate the same temperature distribution as the EUVE DEM analysis .
However , the SIS spectra suggest sub-solar abundances , 0.34 < Z < 0.81 .
Although some of the discrepancy may be the result of incomplete X-ray line lists , we can not explain the disagreement between the EUVE line-to-continuum ratio and the ASCA -derived Fe abundance .

The X-ray surface flux on HD 35850 is comparable to that of cooler dwarfs of comparable age and rotation like EK Draconis ( G0 V ) and AB Doradus ( K1 V ) .
Given its youth ( t \approx 100 Myr ) , its rapid rotation ( v \sin i \approx 50 km s ^ { -1 } ) , and its high X-ray activity ( L _ { X } \approx 1.5 \times 10 ^ { 30 } ergs s ^ { -1 } ) , HD 35850 may represent an activity extremum for single , main-sequence F-type stars .
The variability and EM distribution can be reconstructed using the continuous flaring model of Güdel provided that the flare distribution has a power-law index \alpha \approx 1.8 .
Similar results obtained for other young solar analogs suggest that continuous flaring is a viable coronal heating mechanism on rapidly rotating , late-type , main-sequence stars .