Thursday, October 25, 2007

Comet Holmes Becomes Visible

An obscure periodic comet -- Comet Holmes, designated 17P, suddenly brightened by about a factor of one million starting on Wednesday morning, October 24. From about magnitude 18, so dim that only a large telescope at an observatory would be able to detect it, the comet brightened within hours to magnitude 3, visible with the naked eye, even in the skyglow of a major city like Yokohama -- or Toronto, if the cloud cover would just go away.

A constellation schematic of Perseus and a telescopic finder chart are avilable for observers.

P17/Holmes currently has the appearance of a bright yellow star in the constellation Perseus, comparable in apparent brightness to the other major stars in that grouping. The unusual brightening was probably due to material outgassed from the comet nucleus -- very strange given that perihelion passage (closest approach to the sun) happened a few months ago, and the comet is heading back outwards. The comet itself is part of the Jupiter family of comets -- its perihelion falls outside the Earth's orbit, 2.2 AU from the sun. Its aphelion point is way out around the orbit of Jupiter.

In three of my most favourite places -- northern BC, Lake Herridge in northern Ontario, or rural Newfoundland -- the comet should be quite visible under near ideal conditions -- at least if the sky were cloud free. Clouds in fall/winter are definitely a problem. The advent of Comet McNaught back in January was a complete non-starter for us here -- every night that McNaught would have been visible was a night where it was cloudy in Toronto. But hopefully, we will have better luck with P17/Holmes.

Wednesday, October 24, 2007

Space Update - Chinese Moon Mission and a Historic First for Women in Space

Today, China launched a lunar probe, an orbiter called Chang'E 1 which is designed to orbit the Moon and gather data. The spacecraft is named after the moon goddess.

Chang'E 1 is the second lunar mission launched from Asia this year, intensifying the Asian space race to send human explorers to the Moon. Earlier this month, Japan launched the SELENE mission, the largest and most ambitious lunar exploration spacecraft since the American Apollo and Soviet Luna programs. And next year, India is expected to send their Chandraayan probe.

Also today, the astronauts on the space shuttle Discovery, mission STS-120, spent their first full day in space. They launched yesterday from Cape Canaveral to deliver the Harmony module to the International Space Station.

Discovery, commanded by Pamela Melroy, is scheduled to dock at the International Space Station tomorrow. The current ISS crew, Expedition 16, is commanded by Peggy Whitson. And that is the historic first -- two female mission commanders in space at the same time.

Saturday, October 13, 2007

Doctor Robert Bussard Passes Away

Dr. Robert W. Bussard -- physicist, nuclear fusion researcher, inventor of the Bussard ramjet -- passed away last Sunday morning, October 7. The Power and Control blog has further details.

Dr. Bussard invented the idea of the interstellar ramjet in 1960 -- a concept of using magnetic "scoop fields" to collect interstellar hydrogen, which would subsequently be compressed and burned in a nuclear fusion reaction to produce thrust. This idea worked its way into popular culture via novels such as Poul Anderson's Tau Zero (early 1970s), Carl Sagan's Cosmos TV series (1980s), and even on Star Trek (late 1980s to 1990s).

In the last years of his life, Dr. Bussard worked on prototype nuclear fusion reactors using inertial electrostatic confinement (IEC). This work was done for the US DoD and the US Navy. When his funding ran out, he gave a talk at Google which became famous over the internet. A copy of his Google talk may also be obtained via a peer to peer network with an application such as uTorrent.

I have watched Dr. Bussard's presentation a number of times over the last year. It is both compelling and inspiring -- a succinct synthesis of the science behind nuclear fusion, as well as Bussard's own research into the development of an IEC fusion reactor. Bussard acknowledges that IEC devices represent a completely different direction than the large, expensive, tokamak-based devices which are the mainstream of current international nuclear fusion research.

The IEC research is based on physics known since the early half of the twentieth century. If fully realized, Dr. Bussard's work promises to effectively end humanity's reliance on fossil fuels. More importantly, it would make possible space drives capable of moving a spacecraft from Earth to Mars in a week or Earth to Titan in 70 days. Such a drive could also be the first stage acceleration system to get a Bussard ramjet starship to the threshold speed where its scoop fields would be able to pull in enough hydrogen to achieve ignition.

Thursday, October 04, 2007

Happy Sputnik Day!

Fifty years ago today, the Soviet Union launched Sputnik One, the first satellite. The launch was part of the scientific activity for the International Geophysical Year. Conducted using an R7 launcher, originally intended to carry nuclear warheads, the presence of Sputnik One in the sky sent the world a message, one possibly unintended by the Soviets.
Sputnik was a complete surprise in the West, and the failure of the first two Vanguard launch attempts by the United States created the so-called "Sputnik Crisis" and the idea of the "Missile Gap". The response to Sputnik in America included bringing science and technology education front and centre. For instance, Sputnik did what the Scopes Monkey Trial could not -- it caused all laws restricting the teaching of the Darwinian theory of evolution to be repealed.

Fifty years on, the Soviet Union is no more -- ironically, the same American response to being second best in the race to put the first satellite into space caused a massive economic, social, and technological shift. The shift contributed to the moon landings a decade later, laid the groundwork for the laser and the computer chip revolutions, and likely led to the economic collapse of the Soviet Union in the late 1980s. In other words, Sputnik, and the world reaction to it, is one of the root causes of the world we live in today.

Sputnik is no longer in orbit -- it re-entered the atmosphere and burned up within three months after its launch. But the world that resulted from the Sputnik launch is still here, and still moving forward.

Happy Fiftieth Birthday, Sputnik!