Is there any specific numbers on stars & planets count on Milky Way Galaxy ?
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1$\begingroup$ There are only very rough approximates available. $\endgroup$– SE - stop firing the good guysCommented Mar 22, 2016 at 9:47
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$\begingroup$ @Hohmannfan Not particularly wishing to start an argument, but what is the purpose of your comment, given that both answers make exactly that same point very clearly? $\endgroup$– ProfRobCommented Mar 22, 2016 at 10:25
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A consensus number is that there roughly $10^{11}$ stars in our Galaxy (though this number is certainly uncertain by a factor of at least two, because it is based on extrapolating what we know about stellar populations in our vicinity). Most of these stars are of lower mass and are much less luminous than the Sun.
The number of planets is even more uncertain. It now seems probable that most stars like the Sun have at least one planet, but we really don't know that much about the diversity of planetary systems, how typical something like the solar system is, or how planetary systems might change as a function of position in the Galaxy. We also don't know that much about planetary systems around the dominant (by number) very low-mass stars. They certainly can have planetary systems, but the fraction that do is still a work in progress.
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The number of stars and planets in the milky way can only be given in approximate values.There are about 100-400 billion stars and as of 2016 there are about 2097 planets discovered from 1337 planetary systems.
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$\begingroup$ I think you may have made up the number when you say 1337. Too much of a coinsidence. $\endgroup$ Commented Mar 22, 2016 at 9:45
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$\begingroup$ I got that number from wikipedia! <en.wikipedia.org/wiki/Planetary_system> $\endgroup$– AstrofunCommented Mar 23, 2016 at 5:09
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$\begingroup$ exoplanets.org claims 5428. exoplanet.eu has 2097 $\endgroup$ Commented Mar 23, 2016 at 6:07
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1$\begingroup$ Obviously, this number keeps increasing. It is irrelevant in answering this question, since it is a vanishingly small fraction of the total number. $\endgroup$– ProfRobCommented Mar 23, 2016 at 7:12
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$\begingroup$ @RobJeffries One can only build up a statistically useful estimate by sampling. Of course the sampling method used, light curves or stellar wobbling makes a difference in how you have to do the calculation. 100 billion planets nasa.gov/multimedia/imagegallery/image_feature_2233.html or 8.8 billion earth like planets nbcnews.com/science/… I expect those numbers will be considerably refined over the next couple decades. $\endgroup$ Commented Mar 24, 2016 at 2:09