There are more trees on Earth than there are stars in the Milky Way: scientists explain whether it's true or not
The Internet has repeatedly reported that there are more trees on Earth than stars in our Milky Way galaxy. The first reaction to it is a kind of shock, which gives way to skepticism and the idea that some absurdity is being spread on the Internet again.
However, it turns out that there is a scientific basis that proves the validity of such a statement. Snopes has collected the details.
This message appeared once again at the end of 2023 when a user of the social network X (formerly known as Twitter) shared his surprise.
"There are many more trees on Earth than there are stars in our Milky Way galaxy. That's a lot of trees. But it's also a lot fewer stars than I thought," inigo quilez wrote.
As it turned out, the basis for this statement is a study that was published in September 2015 in the journal Nature. The article, titled "Mapping tree density at a global scale," stated that the number of trees on Earth is estimated at 3.04 trillion.
The authors of that article presented the first spatially continuous map of forest tree density on a global scale. Their work showed that the global number of trees is approximately 3.04 trillion, "an order of magnitude higher than the previous estimate." Of these, approximately 1.3 trillion trees are found in tropical and subtropical forests, 0.74 trillion in boreal regions, and 0.66 trillion in temperate regions.
Meanwhile, NASA does not hide the number of stars in the Milky Way that scientists estimate may exist. Thus, NASA education and outreach specialist Maggie Masetti said that scientists' estimates vary, but they range from 100 to 400 billion stars.
"There are different models for estimating the number of stars in the Milky Way, and the answers they give vary depending on what is used as the average mass of a star. The most common answer seems to be that there are 100 billion stars in the Milky Way at the lowest estimate and 400 billion at the highest. But I've seen higher numbers mentioned," Massetti said.
At the same time, it is worth clarifying that no matter how accurate the numbers of both trees and stars are, counting both has many caveats and limitations.
In particular, it is worth noting that the previous estimate of the number of trees on the planet was made in 2005, and then scientists talked about 400.2 billion trees.
And of course, neither the 2005 study nor the 2015 work provided for a single tree count, so the numbers may still be different.
But the issue of counting stars is not easy either. To be more precise, it is much more complicated because to do so, scientists must determine the mass of the galaxy, given its rotation and its spectrum. Subsequently, researchers try to determine how much of this mass is made up of stars. Most of the mass of the galaxy will consist of dark matter, which is the mysterious substance that binds most of the Universe.
In the end, it all comes down to rough estimates.
Earlier, OBOZ.UA told you that the Earth can survive the death of the Sun but it will not be a victory for life.