The scene in Ferguson, Mo., is certainly an unusual one, especially given how rare it is to see such unrest on American streets.

But it's also easy to think that the situation in Ferguson -- which has been racked by protests and violence since a white police officer fatally shot an unarmed black teenager -- has become a big deal because there's otherwise been a pretty significant news vacuum. With the exception of the killing of American journalist James Foley by the Islamic State this week, there hasn't been much to compete with Ferguson for the attention of cable and Internet news sites -- especially when it comes to politics. (It's August recess, after all.) And sometimes, that means small stories get turned into big ones.

Well, the following chart from Pew should tell us plenty about how Ferguson became such a big story so quickly -- and it's not just because there's been little else to talk about. As the chart shows, the attention Ferguson has gotten on social media ramped up 1) much sooner than it did after Florida teen Trayvon Martin was killed in 2012, and 2) exponentially higher, at its peak.

While social media attention for the Martin case peaked at nearly 700,000 tweets in one day after about a month, attention for Ferguson peaked at more than 3.6 million tweets about a week after the killing of 18-year-old Michael Brown.

A few caveats:

1.) The Martin situation peaked later in large part because people didn't really notice it until three weeks after that shooting, when the 911 tapes were released. But it's also interesting to see the relative interest when President Obama addressed each situation for the first time: 3.6 million tweets for Ferguson and just under 400,000 for Martin -- a 9-to-1 difference, even as both situations were deemed big enough to warrant a presidential statement.

2.) The Brown situation might not have drawn such protests or attention without lingering tensions over Martin's killing and the not-guilty verdict for the man who killed him, George Zimmerman, last year. The two deaths are too similar to be wholly separated from each other. And if Martin happened after Brown, we would think it would have taken off much more quickly (and perhaps bigger) as an issue.

3.) Twitter isn't a perfect measure of interest. There are certainly more Twitter users in August 2014 than in February 2013 (it has grown from 15 percent of the population to 19 percent today, according to Pew), and as mentioned before, the Martin situation was more of a long-term thing -- culminating in the not-guilty verdict a year and a half after the shooting, which obviously isn't shown on the graph above.

But in case there was any doubt whether Ferguson was immediately capturing America's attention more than the Martin-Zimmerman case did, the above chart is pretty illustrative. Ferguson is a really big deal, and it's likely to remain in the news for months to come.