Today's astronomers and cosmologists can hardly do a study on gravity without using the mass to light ratio . From the time of Newton they have not questioned the possibility that it may be the light and not the mass that is doing the gravitational attracting. Below is an experiment that shows that it the light that is doing the attracting. More specifically this experiment indicates that it is the heat transferred inside the test mass coming from the heat source that produces the observed 1.9% change of weight in the test mass.
Four other experiments using different shapes and kinds of test masses show that the heat transferring through them produces a change of weight of the test mass. The observed change of weight in each experiment is -4.9%, 8.9%, 9.6% and 16%. These results have been produced by inexpensive high school lab equipment. Scientists ought to take a day or so off in trying to find the dark matter and dark energy with their multimillion-dollar dark matter detectors and multimillion dark energy satellites to see it they can replicate these easily obtained results.
It could be that scientists for the last 300 years have been deceived by an artifact just like the followers of Aristotelian geocentric astronomy were deceived for 1500 years by the artifact of the earth rotating on its axis every 24 hours which gave the false impression that all the objects in the heavens rotated around the earth in a 24 hour period. For more on this possible artifact that scientists have believed in for the last 300 years in a paper entitled, "Is the warmth of the sun gravitationally attractive?" and more details on the 5 above mentioned experiments go here.