President Donald Trump and North Korean leader Kim Jong Un reached an impasse during their second summit to discuss disarming North Korea of nuclear weapons. They abruptly ended the meeting early and went home without a deal. However, Vanderbilt professor Tizoc Chavez, an expert on presidential diplomacy in the 20th century, sees reasons for optimism in the history of another failed summit – one that took place between Soviet leader Mikhail Gorbachev and Ronald Reagan in 1986.

Tomorrow SpaceX plans to test a vehicle designed to carry astronauts to the International Space Station. Space policy analyst Wendy Whitman Cobb explains how the private company has taken the lead in designing and launching new types of rockets. By dramatically lowering the cost, their innovations are enabling more countries and private entities to get into space.

Not long ago, two biologists met up for coffee and on the way out of the shop used a drink stirrer to scrape up some grime from between the sidewalk slabs. In that sample, they discovered previously unseen single-celled organisms with tiny shells and wiggling pseudopods. Now Mississippi State’s Matthew Brown and Daniel Lahr are using those “micro snails” to look 750 million years back in evolution.