nmap --script=ssl-cert.nse -p 443 gmail.com

ob@cirrus:~$ nmap --script=ssl-cert.nse -p 443 gmail.com

Starting Nmap 7.00 ( https://nmap.org ) at 2015-12-07 15:48 CET
Nmap scan report for gmail.com (173.194.112.21)
Host is up (0.014s latency).
Other addresses for gmail.com (not scanned): 2a00:1450:4001:80b::1015 173.194.112.22
rDNS record for 173.194.112.21: fra07s27-in-f21.1e100.net
PORT    STATE SERVICE
443/tcp open  https

Nmap done: 1 IP address (1 host up) scanned in 0.27 seconds
ob@cirrus:~$ 

[pcaetano@localhost ~]$ nmap --script=ssl-cert.nse -p 443 gmail.com

Starting Nmap 7.00 ( https://nmap.org ) at 2015-12-07 14:48 WET
Nmap scan report for gmail.com (216.58.208.5)
Host is up (0.019s latency).
Other addresses for gmail.com (not scanned): 2a00:1450:4003:805::2005
rDNS record for 216.58.208.5: lis01s13-in-f5.1e100.net
PORT    STATE SERVICE
443/tcp open  https
| ssl-cert: Subject: commonName=gmail.com/organizationName=Google Inc/stateOrProvinceName=California/countryName=US
| Issuer: commonName=Google Internet Authority G2/organizationName=Google Inc/countryName=US
| Public Key type: rsa
| Public Key bits: 2048
| Signature Algorithm: sha256WithRSAEncryption
| Not valid before: 2015-11-26T00:24:56
| Not valid after:  2016-02-23T00:00:00
| MD5:   d058 40ad 47cc b7e7 5ec1 23bf 456b 2f85
|_SHA-1: 8930 281d 80df c71c 6d5f 6df6 2864 134f 7cb7 6d73

Nmap done: 1 IP address (1 host up) scanned in 0.52 seconds
[pcaetano@localhost ~]$