The widespread occurrence of ferroan anorthosites and other magmatic rock types in Apollo lunar samples directly contributed to the construction and development of modern planetary formation models. If the Vesta magma ocean (VMO) model is analogous to the lunar magma ocean model, anorthosites should be present as a late crystallization product of the Vesta magma ocean. However, the lack of anorthositic meteorites unequivocally linked to Vesta or its parent body casts doubts on the existence of a past VMO and to our knowledge of Vesta’s formation and early evolution. Here, we report a newly discovered ferroan anorthosite, Northwest Africa 15118, consisting entirely of anorthite (~94 vol%) and orthopyroxene (~6 vol%). We show that the mineral chemical compositions, whole-rock oxygen isotope composition (Δ¹⁷O = −0.243 ± 0.014‰), as well as chromium isotope composition in chromite (ε⁵⁴Cr = −0.74 ± 0.14), of Northwest Africa 15118 overlaps with howardite–eucrite–diogenite meteorites, indicating a Vestan origin for this meteorite. The occurrence of ferroan anorthosite with prominent positive Eu anomalies supports a primary anorthositic crust layer in Vesta, thus validating the VMO model.

阿波罗月球样本中广泛存在的铁斜长岩和其他岩浆岩类型直接促进了现代行星形成模型的构建和发展。如果灶神星岩浆海（VMO）模型类似于月球岩浆海模型，则斜长岩应该作为灶神星岩浆海的晚期结晶产物而存在。然而，由于缺乏与灶神星或其母体明确相关的斜长石陨石，人们对过去 VMO 的存在以及我们对灶神星形成和早期演化的了解产生了怀疑。在这里，我们报告了一种新发现的含铁钙长石，西北非洲 15118，完全由钙长石（~94 vol%）和斜方辉石（~6 vol%）组成。我们发现西北非15118的矿物化学成分、全岩氧同位素成分（Δ ¹⁷ O = -0.243 ± 0.014‰）以及铬铁矿中的铬同位素成分（ε ⁵⁴ Cr = -0.74 ± 0.14）有重叠含有钙长石-锂长石-闪长石陨石，表明该陨石起源于灶神星。具有显着正 Eu 异常的铁斜长岩的出现支持了灶神星的原生斜长岩地壳层，从而验证了 VMO 模型。