A Surprising Find from the Early Solar System

by | Nov 4, 2008 | | 3 Comments

As if we didn't have enough trouble piecing together how planets form, we're now learning that objects much smaller than planets -- the planetesimals that collide and agglomerate to form planet-sized objects -- can be the subject of melting. The work, led by Benjamin Weiss at MIT, suggests that objects on the scale of 160 kilometers across were large enough to melt almost completely, a counter-intuitive notion that would explain the magnetism found in certain meteorites, which until now has remained a mystery. Weiss' team studied the record of this magnetic field as preserved in three angrite meteorites from the early Solar System. Such study is known as paleomagnetism, examining the record of magnetic fields as preserved in various magnetic minerals, and the angrites involved are thought to record the earliest stages of planet formation. The record of their magnetism extends beyond the lifetime of the early circumstellar disk, leading Weiss to conclude that the fields were produced...

read more

The Hunt for Ancient Antimatter

by | Nov 3, 2008 | | 4 Comments

Antimatter's great attraction from a propulsion standpoint is the ability to convert 100 percent of its mass into energy, a reaction impossible with fission or fusion methods. The trick, of course, is to find enough antimatter to use. We can produce it in particle accelerators but only in amounts that are vanishingly small. There is evidence that it is produced naturally, at least in trace amounts, in the relativistic jets produced by black holes and pulsars. Indeed, a cloud of antimatter 10,000 light years across has been described around our own galaxy's center. And at least one scientist, James Bickford (Draper Laboratory), has worked out ways to extract antimatter produced here in the Solar System, a method that he believes would be five orders of magnitude more cost effective than creating the stuff on Earth. But what about early antimatter, particles left over from the earliest days of the universe? According to prevalent theory, the universe may have been awash with the stuff...

read more

Charter

In Centauri Dreams, Paul Gilster looks at peer-reviewed research on deep space exploration, with an eye toward interstellar possibilities. For many years this site coordinated its efforts with the Tau Zero Foundation. It now serves as an independent forum for deep space news and ideas. In the logo above, the leftmost star is Alpha Centauri, a triple system closer than any other star, and a primary target for early interstellar probes. To its right is Beta Centauri (not a part of the Alpha Centauri system), with Beta, Gamma, Delta and Epsilon Crucis, stars in the Southern Cross, visible at the far right (image courtesy of Marco Lorenzi).

Now Reading

Recent Posts

On Comments

If you'd like to submit a comment for possible publication on Centauri Dreams, I will be glad to consider it. The primary criterion is that comments contribute meaningfully to the debate. Among other criteria for selection: Comments must be on topic, directly related to the post in question, must use appropriate language, and must not be abusive to others. Civility counts. In addition, a valid email address is required for a comment to be considered. Centauri Dreams is emphatically not a soapbox for political or religious views submitted by individuals or organizations. A long form of the policy can be viewed on the Administrative page. The short form is this: If your comment is not on topic and respectful to others, I'm probably not going to run it.

Follow with RSS or E-Mail

RSS
Follow by Email


Follow by E-Mail

		

			
Get new posts by email:

			

				
				
			

			

				
			

		

	


Advanced Propulsion Research




Beginning and End







Archives