After four major plane crashes in the US this week, some travelers are asking whether it’s a coincidence or cause for concern. Experts say the accidents appear unrelated, and that while the timing is unnerving, there is no indication that air travel has become less safe.

Here’s what else you need to know to get up to speed and on with your day.

The Obama Presidential Center will hold its official grand opening ceremony today in Chicago, with political leaders and cultural icons in attendance, alongside performances by several Grammy Award-winning artists. Former President Barack Obama and former first lady Michelle Obama are expected to welcome former Presidents Joe Biden, Bill Clinton and George W. Bush. The campus will open to the public on Friday, coinciding with the Juneteenth holiday. See inside the new $850 million center.

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President Donald Trump signed the US-Iran agreement on Wednesday, concluding his trip to Europe for the G7 summit. The White House then sent a photo of a signed copy to Tehran, where Iranian President Masoud Pezeshkian also signed the document. The agreement says the US will issue waivers allowing Iran to export oil and spells out provisions for reopening the Strait of Hormuz, among other measures. Read the US-Iran peace plan, annotated.