I've now posted the answer in the original post.

Check back next week for another Universe Puzzle!

An artist's representation showing outflow from a supermassive black hole inside the middle of a galaxy. Credit: NASA/CXC/M.Weiss

Step right up — you can now get your very own jetpack. That's right, a real, not-science-fiction-honest-to-goodness jetpack. New Zealander Glenn Martin has been working on perfecting his jetpack for 30 years, and in 1998 created the Martin Aircraft Company to develop and market his idea. Now, the jetpack has become a reality. The 200-horsepower, dual-propeller is designed to fly average-sized person for 48 km (30 miles) in 30 minutes on 18 liters (5 gallons) of gas. The newest model can also reach heights of 2,400 meters (about 1.5 miles). Price? $100,000. "They are a helluva lot of fun to fly," said Martin.

Images of Mars taken from orbit show a massive system of riverbeds and canyons etched by water. Or maybe not. A new study of one channel shows that it was formed by lava flow and not water, and the results make "a strong case that fluid lava can produce channels that look very much like water-generated features," said Jim Zimbelman from the Smithsonian Institution in Washington, one of the researchers. "So, we should not jump to a water-related conclusion when we see such channels on other planets."