To conceptualize the comparison, consider that a human cell is typically around 10 micrometers in diameter. When imagining something on the scale of the universe to compare with this, we might look at the smallest units within the universe.
The observable universe’s diameter is about 93 billion light-years. If we apply a similar scaling factor to that used for cells to humans, we’d look for something approximately 100,000 times smaller within this cosmic scale. One candidate on this scale is a typical star or galaxy compared to a supercluster of galaxies or the full span of the observable universe.
A single star, like our Sun, measures about 1.4 million kilometers in diameter, while a galaxy like the Milky Way spans roughly 100,000 light-years across. So, in a very broad sense, comparing a star to the size of the entire observable universe might approximate this scaling factor. However, due to the sheer vastness of cosmic distances, even this analogy falls short, suggesting how the universe compresses our sense of size into incomprehensible scales.