The exact number of atoms in the universe is not known and is difficult to determine due to the vastness of the universe and the challenges in measuring such quantities accurately. However, scientists have made estimates based on current knowledge and observations.
It is estimated that there are approximately 10^80 atoms in the observable universe. This estimate takes into account the large number of galaxies, stars, and other astronomical objects, as well as the average number of atoms in these objects. Keep in mind that this is an approximation, and the actual number could be different.
It is important to note that the observable universe is just a portion of the entire universe, and the total number of atoms in the entire universe, including regions beyond our observational reach, could be much larger. Additionally, the universe is not composed solely of atoms but also includes other particles and forms of energy.
Overall, the precise number of atoms in the universe remains uncertain, but the estimate of around 10^80 provides a rough idea of the scale involved.