This week's topic challenge is light. You're encouraged to think of and post good questions on this topic.
What is it?
There's a single topic that people think about during the week and come up with good questions on. The topic is set each Wednesday or so.
What do I win?
An Internet with more good questions and answers on an interesting topic.
Who thought of this week's topic, anyway?
How do we decide on next week's topic?
See the call for topic proposals.
What is this section for?
The software won't let me post the question without it, as this question is too similar to existing questions (like last week's topic challenge).
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for Tu Beshvat this Tuesday?