The speed of light is approximately 186,282 miles per second, and a light year is the distance that light travels in one year, which is approximately 5.88 trillion miles. Therefore, it would take a light particle approximately 25 * 5.88 trillion miles / 186,282 miles per second = 8.46 * 10^14 seconds to travel 25 light years.
This time is so large that it is usually measured in years rather than seconds. To convert the time to years, we would need to divide the time in seconds by the number of seconds in a year, which is approximately 31.5 million seconds. This would give us a time of approximately 8.46 * 10^14 seconds / 31.5 million seconds = 26,847 years.
Therefore, it would take approximately 26,847 years for a light particle to travel 25 light years. Note that this is just an approximate value, as the exact time would depend on various factors such as the exact speed of light and the distance traveled.