Truth be told, we do not understand everything about the Universe. This idea got even more accentuated when scientists tried to measure and calculate a specific value called the Hubble Constant. It represents how fast the Universe is expanding outward.
This value was calculated by an astronomer called Edwin Hubble in the 1920s. However, ever since then, scientists have observed and measured the expansion of the Universe. They have found different values of the Hubble Constant. And the exciting thing is that none of them seem to agree with one another.
This difference puts to test out the idea of how old is the Universe, and that’s not all – it puts to test our ability to understand the physics behind its behavior. Of course, there are many questions about this difference. Scientists don’t really understand much of the stars that they are measuring, or even if the model of Universe is incomplete or not.
How did she calculate the Hubble Constant?
In measuring the Hubble Constant, a scientist has calculated it by using a different cosmic landmark, which she also used in her previous experiments. The team measured the brightness or the red giant stars that are found in distant galaxies. These stars reach a size and brightness that’s uniform, so their distance from Earth is quite easy to calculate in comparison to other stars.
Other scientists accept her work, but it is yet to be published in The Astrophysical Journal. She found out that the Universe is expanding at 69.8 kilometers per second for every megaparsec. This rate is quite slower than others have calculated in other studies. In those studies, they focused on a different kind of star, but they still measured the light leftover from the Big Bang. This light is called the cosmic microwave background.