First of all, we have to define what an angel is. If we use the word as it is defined in religious texts, we have no common ground because those who wrote those texts, were primitive people who didn't understand what they had heard, seen or had duplicated from writing ancient texts.
Are there beings that have been seen from time to time who appear to possess divine power? Yes there have been. Who were they? They were and are beings from both divine and advanced societies who are attempting to manipulate a certain situation, which they feel needs immediate attention and thereby- using advanced technology. Something they feel that is important enough to be seen. Every one of these beings, which have been seen or interpreted as an angel, has lived lives as humans on the earth at one time or another. Both divine beings and advanced beings can put on a very spectacular show when they choose to be seen. I've have written a great deal about advanced beings and divine beings and what separates them.
Divine beings have developed the most superior technology in the universe. Advanced beings, are primitive in comparison. Advanced beings aspire to become divine beings through the further development of technology but they will not succeed! In essence, advanced beings took themselves out of the cycle of life and death because they lived at a time when their scientists discovered other dimensional technology which our scientists today are very close to discovering themselves. When they do this, it will be decision time for them. Do they become immortal or do they have faith that a higher power has already given them eternal life?
Divine beings are those who have, through their own effort, become those who can leave the cycle of life and death. These beings do go on to do the same work that we all have an opportunity to do when we leave the planet- to guide humanity but they do it at a very high level and yes, they have been seen from time to time in many guises. With their technology, they can show up dramatically if necessary or they can be subtle. They are messengers and they deliver their message in the way it will be best understood.
When one achieves this level of personal evolution, they are separated from the rest, in a place called Paradisa Christas Eart. Here they carry on their work behind the scenes of helping the rest of us achieve what they have achieved.
Thanks for your questions-I plan to post an article about angels in the near future-