Scientists have gotten very good at measuring the age of things using a variety of techniques, ranging from counting the rings on trees to using highly advanced radiocarbon dating, and much more.

When it comes to measuring the age of objects in space, things can get a little more complex. Then, to measure the age of a star such as our sun, it becomes impossible to be very precise (for now, at least).

For objects in space like asteroids, meteoroids, moons, and planets, scientists can look at the size and composition of the object in question and determine how long it would have taken to form.

In addition, they sometimes get samples of material from these objects that can be studied directly, allowing them to get a much more precise age. This happens when, for example, a mission to the moon brings back rocks or a meteorite crashes down onto Earth.

When it comes to the sun, however, it is impossible to gather a sample since it is so hot. Scientists can analyze its mass and current activity, which lets them know how long it has been ‘burning.’ From this, astronomers estimate that the sun has been illuminated for about 4.57 billion years.

How do scientists determine the age of something more abstract, however, like the solar system itself? They could just say that the solar system began when the sun first collapsed to initiate fusion, which is when it started shining.

Is it really a solar system if it is just a star with no plants? Some people would argue that it is not. In order to be a system, planets need to be orbiting the star.

The oldest planet in our system is Jupiter. In as little as 1.8 million years after the sun was formed, Jupiter was already bringing together massive amounts of space dust, gases, and other elements to form what would eventually become its core, according to a study published in Scientific Reports.

Over the course of many millions of years, the vast majority of the rest of the gas and other elements in the region around the sun condensed into Jupiter and the other planets.

Of course, anyone who looks into space knows that this process is not yet done. There is still the asteroid belt, which is filled with rocks and other material. The rings around several planets are also floating around.

If we were able to fast-forward millions (or billions) of years from now, it is very possible that these things would have formed into a new planet. Or they may end up getting absorbed into existing planets (or even ejected from the solar system entirely).

There are so many factors involved in how solar systems form and evolve that it makes it very difficult to precisely measure when each event happened.

For most things, however, getting ballpark figures that are within a few million years is close enough for astronomers. At least until new methods of measurement are discovered.

If you thought that was interesting, you might like to read about a quantum computer simulation that has “reversed time” and physics may never be the same.