I created a dynamic sitemap, where I generate links from database and output an XML as the result (https://ufotoday.com/sitemap)
Now, since this sitemap is changing all the time, do I need to anything to make google re-scan the sitemap (I'm not sure if they do it by default)
UPDATE:
I'm still unable to confirm with any google official resources that in fact the sitemap is being resubmitted automatically (and discovers new items that show up in the dynamic sitemap), it will be great if anyone can confirm that this is what happening based on their own experience.