AGU website down, outage or expired?

I visited the American Geophysical Union (AGU) website to renew my membership that will expire next month. To my surprise, the AGU site (www.agu.org) did not exist. I tried to access it from different links but it goes to nothing.

The first thing I thought was there could be a site outage. Or maybe the AGU servers are down. This is normally the reason for websites to be inaccessible.

I checked its domain availability and found out that www.agu.org is available for sale. Check the screen shot below (you can click it for a larger view) . I thought of buying the domain but had second thoughts.

Should I buy an expired domain name? Maybe not. Whois.net says otherwise. It says agu.org was renewed on November 4th and will expire on the 10th of July 2019.

Domain Name:AGU.ORG
Created On:11-Jul-1991 04:00:00 UTC
Last Updated On:04-Nov-2009 16:11:59 UTC
Expiration Date:10-Jul-2019 04:00:00 UTC
Sponsoring Registrar:Network Solutions LLC (R63-LROR)
Status:CLIENT TRANSFER PROHIBITED
Registrant ID:23291245-NSI
Registrant Name:American Geophysical Union
Registrant Organization:American Geophysical Union
Registrant Street1:2000 Florida Avenue, NW

Why is the domain available for sale? Is this another scam purporting to help anyone interested to buy an expired domain name when in actual fact the site is taken?