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ACTIVITY: This Threshold Today


This Threshold Today activities ask you to make connections between today’s world and the events of each threshold. In Threshold 4, it is important and interesting to know that the process of accretion not only led to the formation of our planet, but provided all of the natural resources we continue to draw from today.
Debris disks detected in HST archival images of young stars, HD 141943 and HD 191089, using improved imaging processes (24 April 2014). "NASA-14114-HubbleSpaceTelescope-DebrisDisks-20140424" by NASA/ESA, R. Soummer, Ann Feild (STScI). Licensed under Public domain via Wikimedia Commons


The formation of the Earth roughly 4.6 billion years ago was a violent process. Scientists are continually learning more about planet formation in our Solar System as well as in other solar systems. You can join in this process by searching for news stories about solar systems or exoplanets. Record your sources and some of the details about what you discover. Check out Newsela.com for great articles, or look at the Pinterest board Newsela set up on this topic.
Here are some other places to get started with your research:

For Further Discussion

In the Questions Area below, please do the following:
1. Post a link to the article that you found most interesting.
2. List one way that the article connects Threshold 4 to today.
3. Comment on someone else’s link, adding another way that their article connects Threshold 4 to today.
Be sure to check back later to see if anyone commented on your post!

Want to join the conversation?