This pose is called prasarita padottanasana, or, according to yogajournal.com  :

“prasarita = stretched out, expanded, spread, with outstretched limbs

“pada = foot

“ut = intense

“tan = to stretch or extend (compare the Latin verb tendere, “to stretch or extend”)” and asana means pose.

It is also called the “wide-legged forward bend”.

(warning: do not execute without having taken lessons from a certified ashtanga yoga teacher).

Prasarita  and the warrior poses, in my opinion/ experience, are the most structurally stable of the standing poses — it as stable as standing on  your two feet on any ordinary day, if not more stable, because your feet are at wide-angled stance: stable,  safe; there is no danger of toppling or tipping over while your feet are firmly planted on firm ground… (unless you abruptly get up from the pose and the sudden rush of blood makes you dizzy– don’t execute without learning movements in ashtanga classes.) 

(Now playing: “Save a Prayer” originally by Duran Duran; this is an acapella version, artists not indicated by uploader of the audio clip, pls click the audio clip embedded below if this is no longer on autoplay)

    This pose is dedicated to the prayerful † and progressive ∇ : Pray for a better future but don’t forget to prepare and preposition for that future ♥ 🙂