How can the water you get from your tap be older than the Earth, the sun and the solar system?
That’s not possible, right?
And yet, that’s the theory that some scientists have recently come up with. That up to half of the water on Earth is actually older than the Earth itself—and older than the sun and the solar system.
Scientists say that about 30 to 50 per cent of the water molecules on Earth are more than 4.6 billion years old, about a million years older than the solar system.
Scientists at the University of Michigan believe that the water molecules came from ice that was formed in space, before the solar system was formed.
Ilse Cleeves is the astronomer at the university who led the study. She worked with astronomy professor Ted Bergin; their theory was published in a magazine called Science.
Humans, of course, weren’t around when the planets were formed so we can’t know for certain exactly what happened millions of years ago. So scientists rely on complex computer programs to “model” what likely happened.
In this case, the scientists created a computer program that models what likely happened to our solar system over time.
They found that the planetary disk of dust and gas circling the sun, that eventually turned into the Earth, did not create the kind of water we have on Earth today. Therefore, the water must have come from another source that predates the sun.
The researchers’ new theory will join the ongoing scientific debate about how and when our solar system’s water was created.
Related links
An article about the new theory published on the University of Michigan’s website.
The journal, Science. The article about the new theory, published in Science.
CURRICULUM CONNECTIONS
By Kathleen Tilly and Joyce Grant
Writing/Discussion Prompt
Scientists create “theories.” Theories are explanations. Do you believe this new theory about the age of water? Why or why not?
Reading Prompt: Elements of Style
Rhetorical questions are questions that are asked or written and an answer is not expected. The journalist began this article with two rhetorical questions. Why do you think she chose to start the story this way? How do these questions engage the reader?
Junior
Identify various elements of style – including voice, word choice, and the use of hyperbole, strong verbs, dialogue, and complex sentences – and explain how they help communicate meaning (OME, Reading: 2.4).
Intermediate
Identify various elements of style – including foreshadowing, metaphor, and symbolism – and explain how they help communicate meaning and enhance the effectiveness of texts (OME, Reading: 2.4).
Language Feature: Prefix
A prefix is a few letters that is placed at the beginning of a word. For example, in the sentence: ‘Therefore, the water must have come from another source that predates the sun,” the word “predates” has the prefix “pre.” The prefix “pre” shows that the source of the water came from another place before the sun.”
Think of 5 other words that contain prefixes. Using these 5 words, write 5 sentences.
