UNTO THE SECOND GENERATION

The Expedition 18 crew headed for the ISS, blasted off from the Russian steppes on Sunday and is scheduled to arrive at the station today and dock with the Zarya module at 6:33 p.m. Guam time, so docking will have just happened when the ISS appears above our horizon.

The three people aboard are U.S. astronaut E. Michael Fincke, Russian cosmonaut Yury Lonchakov and Richard Garriott, a U.S. computer game developer. Fincke, the only American to launch twice on a Soyuz, will serve as commander of the six-month Expedition 18 mission. The mission's main focus will be to prepare the station to house six crewmembers on long-duration missions.

Richard Garriott will spend nine days on the station under a commercial agreement with the Russian Federal Space Agency. He'll return to Earth on Oct. 23 with Expedition 17 Commander Sergey Volkov and Flight Engineer Oleg Kononenko, who have worked aboard the station since April 10.

Richard Garriot is one of those 'millionaire tourists' that have been helping to foot the bill for the Russian space program, but he has another very interesting distinction. When the spacecraft dock this evening and the hatches are opened, Expedition 17 Commander Sergey Volkov and Richard Garriott will become the first children of previous astronauts to greet each other in orbit. Garriott is the son of former NASA astronaut Owen Garriott, who was a member of the Skylab-3 crew in 1973. Volkov is the son of veteran cosmonaut Alexander Volkov, who flew three Soyuz missions.

So go out tonight and watch the International Space Station and its docked visitors fly over your head. Wave to them. History is about to be made!

The International Space Station is expanding and will soon house six people all the time. We're beginning to have a permanent presence in space and the US is once again gearing up for a return to the Moon. Once we get there, some scientists have discovered a way to help us see things as we've never seen them before.

The really REALLY BIG TELESCOPE!

We need telescopes, those marvels of glass and metal to bring the universe into focus. Although the first ones were made with glass lenses, lenses introduce all sorts of problems into trying to focus light and Sir Isaac Newton discovered that the easiest way to do it is to use a curved mirror. Today, all the world's great telescopes use curved mirrors to bend and focus the light.

But as larger and larger mirrors were built, we discovered that glass sags and large Earthbound telescopes are now made of multiple mirrors. Their images are combined with computers.

TBut there is another way to make large mirrors. Isaac Newton also knew that any liquid, if put into a shallow container and set spinning, naturally assumes a parabolic shape-the same shape needed by a telescope mirror to bring starlight to a focus. This simple physics fact could be the key to making a giant observatory on the Moon.

On Earth, a liquid mirror can be made quite smooth and perfect if its container is kept exactly horizontal and rests on a low-vibration low-friction air bearing that is spun by a synchronous motor. It doesn't need to spin very fast. The rim of a liquid mirror with a 12-foot diameter only has to spin at 3 mph.

Most liquid-mirror telescopes on Earth use mercury. Mercury remains molten at room temperature, and it reflects about 75 percent of incoming light, almost as good as silver. The biggest liquid-mirror telescope on Earth, the Large Zenith Telescope operated by the University of British Columbia in Canada, is 6 meters across; 20% larger than the famous 200-inch mirror of the Hale telescope at Palomar Observatory in California. But the Canadian liquid-mirror telescope cost less than $1 million to build, only a few percent the cost of a solid-mirror telescope of the same diameter-and, for that matter, only a sixth of Palomar's original cost in 1948.

Mercury won't work on the Moon, though: it's very dense and thus heavy to launch, it's very expensive, and it would evaporate quickly when exposed to the lunar vacuum. But work is now being done on a class of organic compounds called ionic liquids. Ionic liquids are basically molten salts. Their evaporation rate is almost zero, and they won't vaporize in the lunar vacuum. They also remain liquid at very low temperatures, a good thing since it gets down to -250 degrees on the Moon at night.

Ionic liquids are only slightly denser than water. Although they aren't highly reflective, a spinning mirror of an ionic liquid can be coated with an ultrathin layer of silver just as if it were a solid mirror. Weirdest of all, the silver layer is so thin-only 50 to 100 nanometers-that it actually solidifies. In the vacuum of space, a liquid mirror coated with a thin solid layer of silver would neither evaporate nor tarnish.

So . . . . how big could lunar telescopes be? Given the Moon's much lower gravity, they could be very large indeed. Lunar telescopes could have mirrors as large as 100 meters in diameter-bigger than a football field.

A mirror that large could peer back in time to when the universe was very young, only half a billion years old, when the first generation of stars and galaxies were forming. And as we have learned with the Hubble Space Telescope, it would also show us things that we never even dreamed of. Here's to the Giant Lunar Telescope and the things it can teach us. And now some space news that could have some dire consequences for all of us.

SPOTLESS

Astronomers who count sunspots have announced that 2008 is now the "blankest year" of the Space Age. As of Sept. 27, 2008, the sun had been blank, i.e., had no visible sunspots, for 200 days of the year. To find a year with more blank suns, you have to go back to 1954, three years before the launch of Sputnik, when the sun was blank 241 times.

"Sunspot counts are at a 50-year low," says solar physicist David Hathaway of the NASA Marshall Space Flight Center. "We're experiencing a deep minimum of the solar cycle."

The image, taken by the Solar and Heliospheric Observatory (SOHO) on Sept. 27, 2008, shows a solar disk completely unmarked by sunspots. We're at solar minimum, a time where there are traditionally very few spots on the Sun. But this particular solar minimum is shaping up to be one of the longest minimums in recent history. If solar activity continues as low as it has been, 2008 could rack up a whopping 290 spotless days by the end of December, making it a century-level year in terms of spotlessness.

Hathaway cautions that this development may sound more exciting than it actually is: "While the solar minimum of 2008 is shaping up to be the deepest of the Space Age, it is still unremarkable compared to the long and deep solar minima of the late 19th and early 20th centuries." Those earlier minima routinely racked up 200 to 300 spotless days per year.

Coinciding with the string of blank suns is a 50-year record low in solar wind pressure, a recent discovery of the Ulysses spacecraft. The pressure drop began years before the current minimum, so it is unclear how the two phenomena are connected, if at all.

What we do know is that the longest period without sunspots occurred in the 1600's. It's called the Maunder Minimum and it coincided with The Little Ice Age, a period of extreme cold in Europe and elsewhere.

What does the spotless Sun mean? Who knows, but I personally will feel a lot better when the Sun goes spotty again!