We've been looking at airplane etiquette for the past five years," Christie Hudson, senior communications manager, Expedia North America, tells NBC News BETTER. "We see some consistencies year over year. The seat-kicker has four years running as the most annoying behavior, and inattentive parents always ranks highly. ] put a swipe of it at the center of your neck to change the smell of the area close to your nose. But be careful with this: you don't want to bug anyone with your scents.
Interstellar travel is still possible, but as far as we know, the best option is to think fairly local for now. The nearest star system to us is Alpha Centauri. In 2016, scientists discovered an Earth-size planet in the habitable zone of one of Alpha Centauri's stars, a red dwarf called Proxima Centauri. Alpha Centauri is close enough to be intriguing: just about four years away if you travel at the speed of light.
But at slower speeds, it's still pretty far. If the Voyager 2 spacecraft (which launched in 1977 and breached interstellar space in 2012) had gone in that direction, it wouldn't reach Alpha Centauri for another 75,000 years. We'll need a quicker solution. Back in 1998, one of Landis' interstellar concepts was funded by NASA's Innovative Advanced Concepts (NIAC) program; NIAC examines far-out ideas for space exploration that may not be used for decades.
Landis said his idea would work for people, but unless you made the spacecraft very small (as Breakthrough proposes doing), you would not get to Alpha Centauri quickly. NIAC continues to fund interstellar studies, as it did in 2017 when it awarded a Phase 1 grant to Heidi Fearn at the Space Studies Institute in Mojave, California. The type of interstellar spacecraft propulsion studied in this grant might use Mach effects to move across the universe. The term "Mach effects" refers to how the rest masses of objects vary as they accelerate, with changes occurring to their internal energies.
Of course, lasers aren't the only solution to getting somewhere far away, and fast. Back in 1958, General Atomics' Ted Taylor and physicist Freeman Dyson of Princeton University worked on an initiative called Project Orion, which would use atomic bomb explosions to propel a spacecraft. But Landis cautioned that the Orion proposal would need between 300,000 and 30 million hydrogen bombs.