Traveling at the speed of light is not currently possible for objects with mass according to our current understanding of physics. However, I can provide you with some information about the vastness of the universe and the scale of galaxies.
The observable universe is estimated to be about 93 billion light-years in diameter. This means that the farthest objects we can observe are roughly 46.5 billion light-years away from us in any direction. It's important to note that the universe may extend beyond the observable universe, but we cannot currently see or measure anything beyond that limit.
Galaxies are vast collections of stars, gas, dust, and other celestial objects. They come in various sizes, shapes, and types. The number of galaxies in the observable universe is estimated to be around 100 billion to 200 billion galaxies.
If we assume that you could somehow travel at the speed of light and traverse the entire observable universe, crossing one galaxy after another, the number of galaxies you could potentially cross would depend on the distance between them. Galaxies are not evenly distributed throughout the universe, and there can be vast distances between them.
To give you a rough estimate, let's consider the lower end of the estimated range, 100 billion galaxies in the observable universe. If we divide the diameter of the observable universe (93 billion light-years) by the number of galaxies (100 billion), we get an average separation of about 0.93 light-years between galaxies. This means that if you could travel at the speed of light, you could potentially cross around 93 billion galaxies within the observable universe.
However, it's important to note that this estimate assumes an average separation and a linear path without any obstacles or gravitational effects. In reality, the distribution of galaxies is not uniform, and the actual number of galaxies you would encounter during such a journey would vary significantly depending on the specific path you take.
Keep in mind that the concept of traveling at the speed of light is purely hypothetical at the moment, and our current understanding of physics suggests that it is not achievable for objects with mass.