I haven’t found anything on line about it yet, but I heard on the television today that in analyzing the Yucatan crater, they’ve determined that the impact occurred hundreds of thousands of years before the dino extinction, so the original Alverez theory may not be true.

On the other hand, much closer to home, both in distance and time, a paper presented at last week’s planetary defense conference speculates that a comet may have caused the Chicago Fire.

Well, that would let Mrs. O’Leary’s cow off the hook. Bossy may be exonerated after all these decades.

Either way, it would still be prudent to keep looking for them and to quickly develop the technological capability needed to deal with any that appear to have our number.

Clark Lindsey points out that the SpaceX Falcon is making steady progress toward first flight. Among all the other milestones noted, I found this one little bit extremely significant:

Regulators gave them “approval to fly the rocket with only thrust cutoff, rather than explosive termination.”… “[This] improves hazardous procedures in transportation, on the launch pad and particularly on recovery of the first stage.” This [was] allowed “due to the all liquid fuel configuration and six-fold valve redundancy.”

As far as I’m aware, the only previous launch system that received permission to fly without range-safety destruct was the SET-1 launch by the American Rocket Company in 1989. The general philosophy has always been that range safety must be able to not only terminate thrust, but destroy the vehicle, should it go out of control. Rockets have always had such range safety devices, and are unique among all other transportation systems in that regard. No ship, train or plane has had devices on board every trip whose sole purpose is to destroy the vehicle.

If SpaceX has gotten permission to launch without it, with only thrust termination, this may be a first for a liquid-fueled rocket (the American Rocket vehicle was a hybrid, with solid fuel and LOX). The big advantage, as it points out, is that there are now no pyrotechnic (explosive) devices on the vehicle, at least not for that purpose, which eliminates some of the steps in launch processing, and post-launch safing, and reduces one of the hazards associated with ground handling (not to mention greatly enhancing the probability of getting the first stage back, even in the event of a mission failure).

Getting such permission is obviously much more important for a reusable vehicle, which the Falcon first stage is advertised to be. They don’t want to have to destroy the vehicle just because it isn’t following the prescribed trajectory, if they continue to have control over it, because they want to get it back.

This is a key breakthrough in reducing launch costs. Let’s hope that it presages the future.

Clark Lindsey points out that the SpaceX Falcon is making steady progress toward first flight. Among all the other milestones noted, I found this one little bit extremely significant:

Regulators gave them “approval to fly the rocket with only thrust cutoff, rather than explosive termination.”… “[This] improves hazardous procedures in transportation, on the launch pad and particularly on recovery of the first stage.” This [was] allowed “due to the all liquid fuel configuration and six-fold valve redundancy.”

As far as I’m aware, the only previous launch system that received permission to fly without range-safety destruct was the SET-1 launch by the American Rocket Company in 1989. The general philosophy has always been that range safety must be able to not only terminate thrust, but destroy the vehicle, should it go out of control. Rockets have always had such range safety devices, and are unique among all other transportation systems in that regard. No ship, train or plane has had devices on board every trip whose sole purpose is to destroy the vehicle.

If SpaceX has gotten permission to launch without it, with only thrust termination, this may be a first for a liquid-fueled rocket (the American Rocket vehicle was a hybrid, with solid fuel and LOX). The big advantage, as it points out, is that there are now no pyrotechnic (explosive) devices on the vehicle, at least not for that purpose, which eliminates some of the steps in launch processing, and post-launch safing, and reduces one of the hazards associated with ground handling (not to mention greatly enhancing the probability of getting the first stage back, even in the event of a mission failure).

Getting such permission is obviously much more important for a reusable vehicle, which the Falcon first stage is advertised to be. They don’t want to have to destroy the vehicle just because it isn’t following the prescribed trajectory, if they continue to have control over it, because they want to get it back.

This is a key breakthrough in reducing launch costs. Let’s hope that it presages the future.

Clark Lindsey points out that the SpaceX Falcon is making steady progress toward first flight. Among all the other milestones noted, I found this one little bit extremely significant:

Regulators gave them “approval to fly the rocket with only thrust cutoff, rather than explosive termination.”… “[This] improves hazardous procedures in transportation, on the launch pad and particularly on recovery of the first stage.” This [was] allowed “due to the all liquid fuel configuration and six-fold valve redundancy.”

As far as I’m aware, the only previous launch system that received permission to fly without range-safety destruct was the SET-1 launch by the American Rocket Company in 1989. The general philosophy has always been that range safety must be able to not only terminate thrust, but destroy the vehicle, should it go out of control. Rockets have always had such range safety devices, and are unique among all other transportation systems in that regard. No ship, train or plane has had devices on board every trip whose sole purpose is to destroy the vehicle.

If SpaceX has gotten permission to launch without it, with only thrust termination, this may be a first for a liquid-fueled rocket (the American Rocket vehicle was a hybrid, with solid fuel and LOX). The big advantage, as it points out, is that there are now no pyrotechnic (explosive) devices on the vehicle, at least not for that purpose, which eliminates some of the steps in launch processing, and post-launch safing, and reduces one of the hazards associated with ground handling (not to mention greatly enhancing the probability of getting the first stage back, even in the event of a mission failure).

Getting such permission is obviously much more important for a reusable vehicle, which the Falcon first stage is advertised to be. They don’t want to have to destroy the vehicle just because it isn’t following the prescribed trajectory, if they continue to have control over it, because they want to get it back.

This is a key breakthrough in reducing launch costs. Let’s hope that it presages the future.

Via Mark Whittington, a piece in the Washington Times on a new age of exploration. The author, Jeremi Suri, asserts that the Bush space policy could be the start of a new age of exploration similar to that of the 17th and 18th centuries. This is certainly the hope of the vast majority of readers of this blog. The devil, as always, is in the details.

The age of exploration had a lot to do with the efforts of Prince Henry the Navigator, who more or less kickstarted the whole thing. Take a look at the timeline from Henry’s early efforts (1420 onwards) until the beginning of real profitable trade (mid 1450s). The real overseas european empires didn’t really take root for another century. Had Henry and his compatriots thrown all their energies into building an empire spanning the globe, they’d never have had the resources to do the little things that lead to the big things. As it is, they had some adventures, made a name for themselves, and some of them got quite rich. Along the way they laid the groundwork for the empires to come.

We are currently at the Henry the Navigator stage, and we should not lose sight of that fact. The next steps are small and modest, but necessary if we are to move on to bigger and better things. Bush was right to put the emphasis on return to the moon first, despite the fact that most commentators can’t seem to get their minds off Mars. Mars will still be there in 30 years, or however long it takes. In the meantime we have the moon right there, staring us in the face. Near Earth Asteroids are being discovered so fast that it no longer makes news unless they are headed for a near collision with earth. Our Azores and our Guinea are waiting within reach.

Also worth checking out is the wikipedia page on Henry.