hey everyone Nico Carver here i often start my videos by saying i'm a deep sky astrophotographer
but i realize there are a lot of terms we use in the hobby of amateur astronomy that really
could use a bit of explanation and a deep sky object or dso for short is one of those terms
so here's my definition based on how people actually use the term in my experience a deep
sky object is any object out in space outside of our solar system excluding individual stars
and the milky way as a whole so let's break this down a bit more and i'll start with the things
that are not deep sky objects the first group are solar system objects and these include the moon
the planets asteroids meteors and comets i'll talk about more about comets next week so i'm
going to be talking about Charles Messier and his famous catalog of not comets the moon and
the planets are of course very bright in our night sky the brightest objects in our night sky
because they're lit by our sun and speaking of the sun the next category of things we don't call deep
sky objects are individual stars so even though by definition all stars other than our sun are
outside of our solar system if it's an individual star we don't call that a deep sky object
the last thing we typically don't call a deep sky object is our own galaxy the milky way
as a whole now of course there are many deep sky objects within the milky way so let's cover now
what is included under the term deep sky object we have star clusters which can be further broken
down into open star clusters like the beehive cluster or m44 and globular star clusters like m13
we have my favorite personally nebulae which can be broken down into many categories
but the main three are emission nebulae like the lagoon reflection nebulae like the pleiades and
dark nebulae like the boogeyman nebula most star clusters and nebulae that we photograph
are inside our milky way galaxies again most star clusters in nebulae are inside the milky way
which leads me to the last big type of deep sky object which is galaxies and to break that
down further galaxies come in many different types uh like spiral galaxies barred galaxies
starburst galaxies irregular galaxies and interacting galaxies okay so that's it now
that you know what a dso is why is this a useful distinction well for the amateur astronomer
astrophotographer the the practical thing you need to know about dsos is that they are usually
dimmer than solar system objects and individual stars there's that we call them faint fuzzies
for a reason and this makes them a lot more challenging to observe at the eyepiece visually
they're slightly less challenging photographically because the camera has this unique advantage of
being able to take long exposures which our eyes can't do our eyes are like high frame rate video
cameras refreshing all the time but of course the long exposures in a camera add new wrinkles
due to earth's rotation so in the end dsos are challenging to both view and to photograph but
they're so beautiful i think that challenge is well worth taking on one last thing and i'm saving
it for last because i realize it's a bit pedantic the more agreed upon term is deep sky but you'll
see many people using deep space and deep sky interchangeably but just you know when people
say deep space object i think they're referring to the exact same thing as a deep sky object
the only reason i bring this up and i think that it gets a little functionally confusing
is nasa named their array of giant radio antennas that receive messages from our interplanetary
spacecraft like the mars rover the deep space network that's the name for the antennas but
they're referring to a communication system for spacecraft within our solar system so to avoid
potential confusion i'll always use the term deep sky object rather than deep space object well that
wraps it up this was the first in a new series i'm calling five minute fridays hopefully i stayed to
that limit and i'm gonna try my best every week to keep it under five minutes next week i'll
be talking about charles messier and the messier catalog and why it's still important to know about
for amateur astrophotographers till then this has been Nico Carver from nebulaphotos.com clear skies