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Chromospheric activity cycles are common in late-type stars; however, only ahandful of coronal activity cycles have been discovered. \ihor\ is the mostactive and youngest star with known coronal cycles. It is also a young solaranalog, and we are likely facing the earliest cycles in the evolution ofsolar-like stars, at an age (~600 Myr) when life appeared on Earth. Our aim isto confirm the ~1.6 yr coronal cycle and characterize its stability over time.We use X-ray observations of iota Hor to study the corona of a starrepresenting the solar past through variability, thermal structure, and coronalabundances. We analyzed multi-wavelength observations of iota Hor usingXMM-Newton, TESS, and HST data. We monitored iota Hor throughout almost sevenyears in X-rays and in two UV bands. The summed RGS and STIS spectra were usedfor a detailed thermal structure model, and the determination of coronalabundances. We studied rotation and flares in the TESS light curve. We find astable coronal cycle along four complete periods, more than covered in the Sun.There is no evidence for a second longer X-ray cycle. Coronal abundances areconsistent with photospheric values, discarding any effects related to thefirst ionization potential. From the TESS light curve we derived the firstphotometric measurement of the rotation period (8.2 d). No flares were detectedin the TESS light curve of iota Hor. We estimate the probability of havingdetected zero flares with TESS to be ~2%. We corroborate the presence of anactivity cycle of ~1.6 yr in iota Hor in X-rays, more regular than its Ca IIH&K counterpart. A decoupling of the activity between the northern and southernhemispheres of the star might explain the disagreement. The inclination of thesystem would result in an irregular behavior in the chromospheric indicators.The more extended coronal material would be less sensitive to this effect.

Multi-wavelength variability of the young solar analog iota Hor. X-ray cycle, star spots, flares, and UV emission