Moscow is about 6 times bigger than Aurora.

Aurora (map shows its 53 named neighbourhoods; the area covers the whole city) is approximately 425 sq km, while Moscow (map shows its 125 districts within the pre-2012 boundary; the area includes New Moscow) is approximately 2,562 sq km, making Moscow 503% larger than Aurora.
Tip: This to-scale comparison of Aurora vs. Moscow uses the Mercator projection, which distorts the size of regions near the poles.
Our free app, MapSize by MyLifeElsewhere — compare any two places, to scale on your mobile device.