NASA - National Aeronautics and Space Administration

The three Expedition 36 crew members on the International Space Station wrapped up another busy week of science experiments and research Friday, while three new crew members prepared to launch from Kazakhstan Tuesday.

Soyuz Commander Fyodor Yurchikhin and Flight Engineers Karen Nyberg and Luca Parmitano will enter their Soyuz TMA-09M spacecraft for a 4:31 p.m. EDT launch, and dock just four orbits – or about six hours – later.

On May 31, 2013, asteroid 1998 QE2 will sail serenely past Earth, getting no closer than about 3.6 million miles (5.8 million kilometers), or about 15 times the distance between Earth and the moon. And while QE2 is not of much interest to those astronomers and scientists on the lookout for hazardous asteroids, it is of interest to those who dabble in radar astronomy and have a 230-foot (70-meter) -- or larger -- radar telescope at their disposal.

As NASA ventures farther into space, whether redirecting an asteroid or sending astronauts to Mars, the agency will need to make improvements in life support systems, including how to feed the crew during those long deep space missions.

NASA's Advanced Food Technology program is interested in developing methods that will provide food to meet safety, acceptability, variety, and nutritional stability requirements for long exploration missions.

Computer simulations of galaxies growing over billions of years have revealed a likely scenario for how they feed: a cosmic version of swirly straws.

The results show that cold gas -- fuel for stars -- spirals into the cores of galaxies along filaments, rapidly making its way to their "guts." Once there, the gas is converted into new stars, and the galaxies bulk up in mass.

The Ring Nebula's distinctive shape makes it a popular illustration for astronomy books. But new observations by NASA's Hubble Space Telescope of the glowing gas shroud around an old, dying, sun-like star reveal a new twist.

The Ring Nebula is about 2,000 light-years from Earth and measures roughly 1 light-year across. Located in the constellation Lyra, the nebula is a popular target for amateur astronomers.