Invisible Universe

This composite image, from mid-July 2002, shows comet 57P broken into at least 19 big pieces as it headed for a close approach with the Sun on July 31st. University of Hawaii astronomers are tracking the pieces in hopes of detecting the dead remnants of the comet. The fragments range in size from tens to hundreds of meters. University of Hawaii 2.2-meter telescope image copyright © 2002 by Yan Fernandez.

Dr. Robert Foot, of the University of Melbourne, Australia, has published a book -- "Shadowlands - quest for mirror matter in the Universe" -- that contains an exposition of his novel theory of "mirror matter" and missing comets. Foot maintains that an unusual number of comets become dormant - stop spewing forth volatile gases that make up their "tail" - after their first pass by the Sun. He sites a computer model that indicates a two-orders of magnitude discrepancy between predicted and actual detection of dormant comets. The discrepancy can be explained if comets are partially composed of "mirror matter."

Foot's work is based on the belief that all fundamental interactions are mirror symmetric. Mirror matter is the symmetric image of ordinary matter. Mirror photons, electrons, protons, etc. do not interact with ordinary matter, but they do have mass and are affected by gravity. This means mirror and ordinary matter can clump together, but react differently when exposed to interactions with ordinary matter. "As for the missing comets, they could simply be mirror comets with embedded ordinary matter. Once they have passed the Sun, their ordinary volatile components progressively burn off leaving an invisible mirror matter core. This would explain why so many simply fade away," he says. 

"If mirror matter exists, then there should exist also mirror stars, mirror planets, even mirror life." 
-- Dr Robert Foot, of the University of Melbourne

If mirror matter exists, it would fall into the class of "dark matter" - unseen matter whose gravitational effects dominate the Universe.

Foot even links the 1908 blast in Tunguska, Siberia, and a much smaller Jordanian blast, that happened in 2001, as evidence for mirror matter bodies. Witnesses for both events saw an object streak across the sky and heard an explosion. The lack of a meteor body material baffles scientists in both cases. Foot contends that the blast sites could contain tons invisible mirror matter. Recent experiments also indicate that there may be a new force that connects ordinary and mirror matter - this would allow mirror asteroids to heat-up and explode if they entered Earth's atmosphere.

"If mirror matter exists, then there should exist also mirror stars, mirror planets, even mirror life," says Dr. Foot.

More information:

The University of Melbourne (Australia); July 23, 2002; Press Release: "Ghostly asteroids clue to missing matter"

Distant Craft Fades Away …

A recent contact with the most distant spacecraft -- Pioneer 10 - may have been the last. On July 14, 2002, the Deep Space Station (DSS) near Madrid was unable to lock onto Pioneer's signal for more than a minute at a time. The signal was at the threshold of delectability. The contact attempt actually began a day earlier, when the DSS dish at Goldstone, California, asked Pioneer to transmit data to Earth.

Recent contact attempts have not always been successful, but a prior attempted in March - to mark the 30th anniversary of launch - did go through. Currently 80.82 times the Earth's distance from the Sun, Pioneer 10 is twice as far as the planet Pluto. The sturdy craft is traveling at 12.24 km/sec (27,380 mph) and has a round-trip radio communications time of 22 hours 37 minutes.

More information:

SpaceDaily.com; Jul 26, 2002; Tech Space: "Fading Echoes Of A Distant Pioneer"

… Another in the Wings?

Proposed "New Horizons" spacecraft in the Kuiper Belt. (JHUAPL/SwRI)

The National Research Council has issued a report recommending that Pluto and objects in the Kuiper Belt be given priority in NASA's exploration of the Solar System. The Council sites the fact that studies of this region of space may yield information on how life formed on Earth: the comets and asteroids in the Belt could have brought water to Earth after the creation of the Solar System. "They are the only mechanism we know to bring water and biological materials to a sterile Earth," said Michael Belton, who chaired the report committee.

While Pluto is the largest object in the Kuiper Belt, much about this world is unknown: it is the only planet that has not been visited by spacecraft. What is known about planet has sparked occasional debates as to its internationally recognized status as a planet.

The report recommends a series of probes be launched toward Pluto and the Belt every 18 months between the years 2003 and 2013.

In the past two years there have been budget battles between Congress and the Administration over the inclusion of a Pluto mission in the NASA budget.

More information:

Reuters; July 11, 2002; News wire: "We Want Pluto, Scientists Plead"