Space Fuel Depots

NASA has let contracts to four companies to study the concept of establishing fuel depots in space. NASA and many space advocates argue such celestial gas stations will be necessary for both deep space exploration and space colonization. Indeed, the space policy of the Obama administration emphasizes building infrastructure to support a long term human presence in space.

The four companies will look at strategies for establishing a system of depots, as well as define the technologies required. Perhaps the key problem to overcome is determining how to store super cold rocket fuels for extended periods in the glare of the Sun. Of course, creating such a system assumes chemical rockets will be the workhorses of the transportation system. Ion engines will likely power slow cargo ships into deep space relatively early in that coming era. Solar sails will also probably have a role. For faster flights, nuclear-powered rockets will be used in decades to come. Until then, however, chemical rockets will take us wherever we go, and those will be more efficient if we have fuel depots at key points in space.

Juno On Its Way

NASA successfully launched its Juno spacecraft yesterday. In five years, if all goes well, Juno will reach Jupiter and insert itself into an elliptical polar orbit around the giant planet.

Juno is scheduled to spend one Earth year orbiting Jupiter and studying its internal structure, including its magnetic and gravitational fields. At the end of its mission, the probe will be deliberately crashed into the planet to preclude any possibility of it ever crashing into one of Jupiter's moons that might harbor life.

The decision to crash into the planet is curious. Surely there is an orbit it could be put in that would keep the probe away from the moons, and which would allow it to be retrieved at some point in the future. That would have historical and, presumably, scientific value. Beyond that, life somewhere in Jupiter's vast and complex atmosphere is not completely out of the question. So, mission planners are making the judgment that life on one of the moons is more likely than life in Jupiter's atmosphere. Whether we know enough yet about life, or the moons, or Jupiter itself is another matter.

New Evidence For Martian Water

Scientists studying images taken by the Mars Reconnaissance Orbiter have found slopes on the surface of Mars have channels that seem to have been cut by liquid water flowing on the surface. The channels appear in lower lattitude areas, where temperatures can climb to levels that would allow liquid water to exist. Further, the channels seem to change with the seasons, drying up in winter and expanding in the spring, a pattern consistent with water freezing in winter and flowing again in the warmer springtime.

Science has been comfortable for several years saying water ice existed in the Martian polar caps and underground. The channels in the slopes suggests liquid salty water has flowed recently on the surface-- and may exist even today, at least near the equator during the warmer seasons. "Warmer" in a Mars context is relative, of course. The land that may support this water is similar to permafrost in Siberia.

Flowing water, of course, increases the chances for life on Mars. Perhaps even more importantly, it increases the chances for life in places we could reach easily, first with rovers and later with human explorers.

Musk On Mars

Elon Musk, founder of and driving force behind SpaceX, recently reiterated in public has goal of sending humans to Mars within 20 years, if not sooner.

Musk says astronauts could make the trip in a Dragon capsule. That probably needs more thought. Technically, he may be right, but people living in a capsule for that long? Dragon needs to be the taxi taking the Mars crew to a large interplanetary ship assembled in space-- perhaps using Bigelow inflatable module technology.

My two cents.

Twenty Miles For Opportunity

NASA's Mars rover Opportunity recently passed the twenty mile mark in its travels across the Martian surface. That's a remarkable achievement for a vehicle that was meant to travel only 0.37 miles in its original, 90-day mission. That mission has become a more than seven year trek.

Opportunity's goal for the past couple of years has been the 14-mile wide crater, Endeavour. Scientists believe Endeavour's outcroppings hold significant data about the geological history of the planet. When Opportunity was first pointed towards Endeavour, it was a goal no one was sure Opportunity could reach. Now, it should reach the crater in just a few days.

Taurus 2 Delay

The initial flight of Orbital Sciences' Taurus 2 rocket will be delayed two months, into December for now, as the company works a fuel line problem. Such delays are not uncommon in the development of new rockets, and OSC says this delay will not materially affect its overall program.

The Taurus 2 rocket and the Cygnus capsule are OSC's answer to SpaceX's Falcon 9/Dragon configuration. Both companies are working with NASA to build systems able to deliver cargo to ISS.

Dawn Begins Work

NASA's Dawn spacecraft, in orbit around the huge asteroid Vesta, has returned its first close-up images. They show the surface of Vesta in unprecedented detail, revealing a world battered by impacts, but also a world shaped by internal processes.

Dawn will begin streaming back other kinds of data this month, and the plan is for Dawn to photograph Vesta from three different orbits over the next year, giving planetary scientists different perspectives on the surface features and how they inter-relate.