Using Gaia Early Data Release 3 (EDR3) parallaxes and Bayesian inference, we infer a parallax of the Westerlund 1 (Wd1) cluster. We find a parallax of 0.34 0.05 mas corresponding to a distance of kpc. The new Gaia EDR3 distance is consistent with our previous result using Gaia Data Release 2 (DR2) parallaxes. This confirms that Wd1 is less massive and older than previously assumed. Compared to DR2, the EDR3 individual parallax uncertainties for each star decreased by 30%. However, the aggregate parallax uncertainty for the cluster remained the same. This suggests that the uncertainty is dominated by systematics, which is possibly due to crowding, motions within the cluster, or motions due to binary orbits.

使用 Gaia Early Data Release 3 (EDR3) 视差和贝叶斯推断，我们推断出 Westerlund 1 (Wd1) 集群的视差。我们发现对应于kpc 距离的视差为 0.34 0.05 mas。新的 Gaia EDR3 距离与我们之前使用 Gaia Data Release 2 (DR2) 视差的结果一致。这证实了 Wd1 的质量和年龄都比之前假设的要小。与 DR2 相比，EDR3 每颗恒星的个体视差不确定性降低了 30%。然而，集群的总视差不确定性保持不变。这表明不确定性由系统学主导，这可能是由于拥挤、星团内的运动或双星轨道引起的运动。