Honda's CNG Civic is the only natural gas-fueled sedan currently available in the United States. With so few CNG passenger cars on the road, pumping stations are few and far between.
Credit Tracy Samilton for NPR
Dodge currently offers a CNG-fueled truck. A group of state governors hope Detroit will soon build CNG sedans, as well.
More than 20 state governors are taking an unusual step to boost the natural gas vehicle industry. Independent of the federal government, they're asking Detroit carmakers to build them a new kind of car: a midsize sedan that runs on compressed natural gas instead of gasoline.
The governors are hoping to boost demand for natural gas cars with their collective buying power. Combined, the states say they could ultimately buy thousands of CNG vehicles to replace their current vehicle fleets — if those cars were available.
NASA engineer Adam Steltzner led the team that designed a crazy new approach to landing on Mars.
Credit NASA
This artist's concept shows thrusters firing to steer the spacecraft as it enters Martian atmosphere. The Curiosity rover has traveled for more than seven months inside the spacecraft.
Credit NASA
Friction with the Martian atmosphere helps slow the spacecraft as it descends. It also heats the heat shield. Friction alone accounts for almost all of the deceleration needed for landing.
Credit NASA
A parachute more than 50 feet across pops out, adding a bit more braking as the craft sinks into Mars's lower atmosphere.
Credit NASA
With the heat shield jettisoned, the rover can be seen tucked into the backshell of the spacecraft.
Credit NASA
Rocket thrusters provide the last little bit of deceleration. At the same time, radar clicks on, giving the craft information about its speed and distance from the surface.
Credit NASA
Here's where things get crazy. A new "sky crane" lowers the rover on three cables while hovering above the surface.
Credit NASA
Once the sky crane senses that it's no longer supporting the rover, it releases the cables and flies off to crash-land a safe distance away. Curiosity is now free to explore its new home.
Credit NASA
Airbags: They don't work because Curiosity is much heavier than past rovers.
Credit NASA
This is it! Lowering the rover on a cable makes it easier for the landing system to know when the rover's actually on solid ground.
Credit NASA
Legs. Too unstable; rover will tip over.
Credit NASA
Pallet: A wider base and more legs still isn't enough to overcome stability issue. Too wimpy.
Credit NASA
The Mars Science Laboratory spacecraft will approach Mars at 13,000 mph. The entry, descent and landing process has to guide it to a soft landing.
Look for a review of the new science fiction epic "Total Recall" and you'll see headlines ready Total Makeover. You might recall the 1990 original starring Arnold Schwarzenegger. With our review of the remake, here's Kenneth Turan.
Over the next few years, the Affordable Care Act will probably boost demand for nurses to take care of the newly insured, she says, "and I need faculty to teach the practitioners that are going to take care of these uninsured."
Gymnast C.J. Maestas has been tumbling since he was 18 months old. His grandfathers Frank Barela (left) and Frank Maestas have been a lifelong source of support.
As fans around the world are riveted to the 2012 Summer Games in London, one young gymnast already has his sights on 2016.
Albuquerque, N.M., native C.J. Maestas, 20, has been tumbling his entire life. A self-described "hyper" kid who loved to climb on things, C.J. joined his first gymnastics class when he was 18 months old.
"As a little baby, you were always jumping," C.J.'s grandfather Frank Maestas recalls.
South African poet Mbali Vilakazi is also a performer and radio producer based in Cape Town. Vilakazi's poem pays tribute to South African swimmer Natalie du Toit, the first female amputee ever to qualify for the Olympic Games.
Gabrielle Douglas performs Thursday on the beam during the artistic gymnastics women's individual all-around final. Some people are focusing on her hair rather than her skill.
Gabby Douglas, the 16-year-old gymnast from Virginia Beach, Va., won another gold medal Thursday. The first was won with her team earlier this week. She was the only member of the team to perform in all four rotations. So, why are some black women obsessed with her hair? Writer Monique Fields has this perspective.
Never mind how she flies like a raven on the balance beam. Or flutters across the floor. Or soars on vault. Or swings on the uneven bars.
The West Nile virus is back, and it's looking like it could be particularly bad this year. As as result, federal health officials are warning people to protect themselves against the mosquito-borne infection.
The West Nile virus first showed up in the U.S. in 1999 and quickly spread from coast to coast, raising widespread alarm. Some have argued that red-breasted robins play a key role in the spread of the virus.
