Could the fact that the sidewalks of both Bangkok and Pittsburgh feature tile mosaics of space aliens be a coincidence? That they are the exact same size, with the exception of one small tile? What was each artists' source of inspiration? There are a few cultural insights that can be gleaned here, perhaps some "tile-alien norms" if you will. Bangkok's distinctively more
Space Invaders-like alien lives on the sidewalk just outside of Sukhumwit Soi 21, near a
trendy new retail experience designed to mimic an airport terminal. All sorts of good stuff there - impressive attempt to package the burgeoning desire for Thais to join the ranks of the global cosmopolitan jet set, or rather give the Thais who already claim membership a greater sense of validity in their ability to critique shortcomings in accuracy ("In real airports that I've been in, the models of the Golden Gate Bridge were not this large."). Thankfully, Thai airport-like malls have more reasonable food prices (and far more food and retail options) than the Thai airports I've visited. This mall may augur well for global airports whose designers would take notes and adopt a more customer-centric approach towards airport design/refurbishing.
The Steel City alien was spotted in the up-and-coming East Liberty neighborhood, whose moderately-paced gentrification has been kicked into overdrive with the opening of a Google campus. This character appears to be an homage to the classic American Area-51/Roswell style of space aliens.
Note what becomes accented about each alien once the mosaic medium is adopted: Thai alien gets more expressive, less threatening eyes than the American, while the American alien's gesture would most likely be interpreted as a friendly wave ("I come in peace/pieces").
There may also be some relevant insights to pull out of the fact that they are almost-but-not-quite-identically sized, though placed at different heights. The Thai Space Invader clocks in at 143 tiles (142 tiles if you count that missing one above its antenna there) and sized 11x13 tiles, and is doing its thing right at ground level on a fairly high-pedestiran trafficked area. The American, waving hello farther up at eye level, is tucked discreetly into a sidewalk alcove on a relatively less crowded street. At 12x12 tiles, this more symmetrical work clocks in at 144 tiles.