The following notification channels are available for email subscription. Directions for subscribing and unsubscribing are provided below.
The SSD announcements notification channel provides content related to generally significant changes to the SSD website and/or provided services (such as Horizons). Announcements from this channel are typically infrequent (perhaps one every few months).
These announcements are also available on this web site.
How to Subscribe:
To subscribe to the SSD announcements channel, send email to
How to Unsubscribe:
To unsubscribe from the SSD announcements channel, send email to
Be sure to use the same email address you used to subscribe to the list.