Use iw device scan to show all information about currently visible networks. The output has more than an entire screenful per network, so use grep to trim it down:
$ sudo iw wlan0 scan | egrep "^BSS|SSID:" BSS 24:a4:3c:9e:d2:84(on wlan0) -- associated SSID: eduroam BSS 24:a4:3c:ae:df:83(on wlan0) SSID: Example multi-AP network BSS dc:9f:db:30:c1:7a(on wlan0) SSID: Example multi-AP network BSS 00:19:3b:99:e2:80(on wlan0) SSID: TEO Wi-Fi For some very old Wi-Fi card drivers, you'll need the iwlist device scan tool instead:
$ sudo iwlist wlan0 scan | egrep "Address:|ESSID:" Cell 01 - Address: 24:A4:3C:9E:D2:84 ESSID:"eduroam" Cell 02 - Address: 24:A4:3C:AE:DF:83 ESSID:"Example multi-AP network" Cell 03 - Address: DC:9F:DB:30:C1:7A ESSID:"Example multi-AP network" Cell 04 - Address: 24:A4:3C:9E:D2:16 ESSID:"Example multi-AP network" Aircrack also comes with the airodump-ng tool which repeatedly shows all networks it sees. (You need to enable monitor mode first, using airmon-ng.)