Tuesday, August 02, 2005

NEO and Deep Impact Updates...........


Howdy folks- yes I know I've been neglecting the blog. It's partly due to a busy summer and partly due to a little blogging burn out so to speak. I just haven't felt the urge to blog like I used to lately. I predict that will change in the future. I have to stay the hell away from women for a while though. Apparently I have USE ME written on my forehead, and I can't seem to wash it off.

In any case, these two stories definitely deserve whatever increased attention they can get..

Schweickart Proposes Study of Impact Risk from Apophis (MN4)

By: David Morrison

Rusty Schweickart and the B612 Foundation have asked NASA to further study the possibility that this asteroid might return to hit the Earth after its close approach in 2029.
Note: Asteroid 2004 NM4 has been named 99942 Apophis, where Apophis or Apep was an ancient Egyptian god of evil, destruction and darkness. Dave Tholen at University of Hawaii explains this name: "It is traditional to name Aten-class asteroids after Egyptian gods. While it is an Aten-class object now, MN4 will become an Apollo-class asteroid after the 2029 close approach, and Apollo-class asteroids have traditionally been named after Greek gods. So we selected the Greek name for an Egyptian god. Apophis is the Greek name for the Egyptian god Apep, the god of evil and destruction. Apep was usually thwarted in his destructive efforts, however. Apophis isn't going to get us, at least this time around".

Last December, asteroid Apophis (2004 MN4) briefly rose to Torino Scale 4, when orbital calculations suggested a greater than 1 in 50 chance of collision on April 13, 2029. Subsequent optical and radar observations showed that Apophis will not collide with Earth in 2029, but it will come very close (see "Asteroid MN4 and How to Protect the Earth" in the News Archive for April 25, 2005). Current interest (and concern) is directed at possible future impacts, if Apophis should pass through a "keyhole" in 2029 and find itself in a resonant orbit (such as one in which the asteroid makes exactly 6 orbits of the Sun in 7 years, returning to Earth's vicinity every 7 years.) A keyhole is a small region of space that leads an asteroid back to hit Earth on subsequent encounters.

Based on current knowledge of the orbit of Apophis, we cannot exclude the possibility of it passing though a keyhole and hitting the Earth on a subsequent pass. However, there will be opportunities to make improved optical and radar observations, which are likely to confirm that it will miss the keyholes. It would also be possible to place a transponder on the asteroid and use this to verify whether or not it will pass through a keyhole in 2029. The issue is whether the ground-based orbital improvements will come in time to make a mission decision, or whether we need to plan for a transponder mission in any case.

Why the hurry? It is because if we should need to deflect the asteroid (which is unlikely but possible), our technology requires that the deflection take place before the close flyby in 2029. Before 2029 we only need to it enough to miss the keyholes (which are less than 1 km across). But if a deflection were required after 2029, it would have to be enough to miss the much larger target of the Earth itself, which is far beyond present technology for as asteroids this large.

In a letter to NASA Administrator Michael Griffin, Rusty wrote the following-

The augmentation we propose to our ground tracking capability is the launch and subsequent docking of a scientific mission, including a standard radio transponder, with 2004MN4. While the improvement in our knowledge of the asteroid's orbit would resolve the issue of a potential impact, the scientific knowledge gained of both the surface and interior characteristics of the asteroid would be invaluable for future operations in and of itself. The unique circumstance presented by this asteroid which might have to be deflected, whose size makes it probable that it has a "rubble pile" structure, and whose orbit will bring it within the range of distorting terrestrial tidal forces, makes this a very attractive learning opportunity.

Look folks, with a $16 billion budget, the ABSOLUTE LEAST thing NASA could be doing in terms of dealing with NEO's would be to tag Apophis with a radio transponder. Considering the money pit in the sky known as the International Space Station, not to mention the Chevy Vega of space programs in the Shuttle, NASA needs to spend money on things that are actually, you know, USEFUL. The Shuttle program is turning in to a death trap, the current one in space is already experiencing similar problems that caused the last Shuttle to break up upon re-entry. I am all for human exploration of space, but until we have a viable means of traveling that we know can safely return 100% of the time, the risk just isn't worth it. Maybe when the payoff was proving that we could land on the moon, thus beating out the Russians, the risk was worth it. But that time is passed. No one can compete with the US in terms of what we bring to the table in space exploration. Knowing this, we should be actively working towards attainable realistic goals that are beneficial in the long and short terms. For instance, spending $100 million out of a $16 billion dollar budget to tag Apophis is reasonable and will give us much useful information with which we can react accordingly.

There is no point on spending a single dime on anything else if Apophis is shown to be a definitive calculated threat.

And speaking of useful programs that are performing above and beyond the wildest expectations, I give you the latest update from the Deep Impact satellite.


As NASA's Deep Impact flyby spacecraft prepares to execute its sixth trajectory correction maneuver, program managers at agency headquarters in Washington are investigating future options.

Today's scheduled burn places the spacecraft on a trajectory to fly past Earth in late December 2007. The maneuver allows NASA to preserve options for future use of the spacecraft.

"This maneuver will keep the spacecraft in the vicinity of the inner planets, thereby making the task of tracking and communicating with it easier," said NASA's Director of Solar System Division, Science Mission Directorate, Andy Dantzler.

Dantzler announced today that all investigators interested in using the Deep Impact Flyby Spacecraft for further science investigations must submit proposals to the 2005 Discovery Program Announcement of Opportunity for a Mission of Opportunity.

"All proposals for use of the Deep Impact spacecraft will be evaluated for science merit and feasibility along with all submitted proposal for Missions of Opportunity," he said. "The spacecraft is being offered as is. Proposers must include mission management and spacecraft operations in the total proposed funding."

Further details will be posted by the end of July on the Discovery Program acquisition site: http://centauri.larc.nasa.gov/discovery

As we can clearly see, the programs that have comparatively used the least percentage of the NASA budget such as Deep Impact Mission and the Cassini Huygens Mission have returned much more than we could have hoped for in terms of useful data. The proposal that Rusty has put forth is reasonable and would be the best usage of our current NASA dollars at the given time.

Update: This post would not be complete without including this unbelievably cool picture from Saturn. It's freaking amazing-

Believe it or not, this extreme close-up of Saturn's swirling clouds was acquired from more than one million kilometers (621,370 miles) from the gas giant planet. The rings' image is severely bent by atmospheric refraction as they pass behind the planet.
The dark region in the rings is the 4,800-kilometer-wide (2,980 mile) Cassini Division.

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