What Percent of the Visible Objects Seen in the Night Sky with the Unaided Eye are Beyond our Galaxy and Solar System?

-- Charles | September 10, 2020

Question:

What percent of the visible objects seen in the night sky with the unaided eye are beyond our galaxy and solar system?
Thanks.

-- Charles

Answer:

Since the unaided eye is really only sensitive to a small fraction of the stars in our Galaxy (about 9000 stars out of about 100 billion, or 0.0000045%), seeing anything beyond our galaxy is a real challenge. With few exceptions, the Andromeda Galaxy, which is just visible to the unaided eye, most objects found in the night sky beyond our solar system and galaxy are not detectable with an unaided eye.

-- Jeff Mangum

Facebook

Twitter

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.
	Founded in 1956, the NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media.
	The National Science Foundation (NSF) is an independent federal agency created by Congress in 1950 "to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense..."
	AUI collaborates with the scientific community and research sponsors to plan, build, and operate cutting-edge facilities. We cultivate excellence, deliver value, enhance education, and engage the public.