Singer Miley Cyrus: Still alive, still pretty zany. (Carlo Allegri/Reuters)

There is so much fake stuff on the Internet in any given week that we’ve grown tired of debunking it all. Fake Twitter fights. Fake DHL ads. Amazing viral video? Nope — a Jimmy Kimmel stunt!

So, rather than take down each and every undeservedly viral story that crosses our monitors each week, we’re rounding them all up in a quick, once-a-week Friday debunk of fake photos, misleading headlines and bad studies that you probably shouldn’t share over the weekend.

Ready? Here’s what was fake on the Internet this week:

1. Bikers did not “surrender” the Brooklyn Bridge to pedestrians. But a tweet by the (clearly) marked parody account @BicycleLobby fooled several major news outlets into thinking they did — the AP and New York Daily News, included. The account, which tweets jokes about biking to a smallish audience, claimed it had planted the mysterious white flags that recently appeared on the Brooklyn Bridge. In reality, of course, @BicycleLobby is just a fun Twitter account, and the flags are still a mystery.

2. That Facebook tribute to MH17 victims … might not be. As if to further prove that Facebook scammers are an exploitative, shameless bunch, a number of them set up bogus “memorial” pages for MH17 victims in the immediate wake of the crash. These pages, predictably, had no affiliation with the family or friends of the deceased. Many contained misleading links to drug or hook-up Web sites; some also contained spamware that could download malicious files, if clicked.

3. Crazed Chicago teens did not riot after seeing “The Purge.” That widely shared and entirely fictional article — which has, of this writing, been posted to Facebook more than 100,000 times — comes from the “satire” site Cream BMP Daily, one of the worst perpetrators of dumb, fake Internet things. The Purge has, however, inspired some real copycat weirdness: Over the weekend, hundreds of Twitter users posted revenge porn on a hashtag associated with the horror movie.

4. There are no sharks in Lake Ontario. Americans and Canadians alike were alarmed to learn that a shark had surfaced in one of the Great Lakes, where — according to a YouTube video! — it pulled a fish from the line of a dude fishing off a dock. Canadian news outlets were quick to note the heavy skepticism among local experts. But the rumors weren’t quite put to rest until late last week, when the Discovery channel apologized for, you guessed it, the Shark Week marketing stunt. (For the record, the scariest fish in the lake — lake sturgeon, which can reach upwards of six feet — were fished almost to extinction in the 20th century.)

5. Air Force One did not crash over Russia. But reports that the president’s plane went down over Russian air space did appear on the Facebook page of the Wall Street Journal when the paper’s account was hacked Sunday morning. WSJ deleted the posts within 20 minutes and promised to “look into” the compromised page.

6. Miley Cyrus is not dead. This latest round of morbid speculation was started by a Facebook scam and fueled by Cyrus’s failure to post to Instagram for three days. To the enormous relief of her fans, Cyrus debunked the rumors with a topless Instagram on Tuesday. (For the record, the scammers’ description of Cyrus as a “country singer” should have tipped us all off.)

7. The moon landing never happened. Kidding!! It absolutely did. But in honor of the 45th anniversary of the landing, and in the name of knowledge/decency, we feel obligated to remind you that claims to the contrary are demonstrably false.

Did we miss any other notable fake stuff this week? E-mail — or stay tuned until next week, because surely some more shenanigans will go down in the meantime.