HD 59435 is a double-lined spectroscopic binary (SB2), with slowly rot
ating components of very similar luminosity. It was studied through hi
gh-resolution spectroscopy, photometry and CORAVEL observations.(1) Or
bital elements are presented. The orbital period is 1387 days. The lin
e of sight lies close to the orbital plane, but no eclipses have been
observed so far. The primary is an evolved G8 or K0 star, which has li
kely just descended the Red Giant Branch. The secondary is a cool Ap s
tar close to the end of its main-sequence life. It shows lines resolve
d into magnetically split components, from which its mean magnetic fie
ld modulus can be diagnosed. The field varies with a remarkably large
relative amplitude, over a rotation period which is at least of the or
der of 3 years.