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Comet put on list of potential Earth impactors
New Scientist ^ | 1 June 2005 | David L Chandler

Posted on 06/02/2005 9:04:31 AM PDT by SunkenCiv

On 26 May, JPL's unique orbital calculation software determined that Comet Catalina was on what could possibly be a collision course with Earth, though the odds of such an impact were small: just 1 chance in 300,000 of a strike on June 11, 2085. Based on the 980-metre size estimate, that would produce a 6-gigaton impact - equivalent to 6 billion tonnes of TNT.

Astronomers expected the addition of further observations to the calculations to rule out any possibility of a collision, as happens with most newly-seen objects.

But that did not quite happen. The comet's predicted pathway actually drew even closer to making a perfect bull’s-eye with the Earth - its predicted path passes within 1000 kilometres of the where the centre of our 12,700-km-diameter planet will be around that time.

However, uncertainty in the exact timing of the comet’s pass through the line of Earth’s orbit dropped the odds of an impact to about 1 in 120 million. That is very low, but the observations so far cannot categorically rule a collision out.

(Excerpt) Read more at newscientistspace.com ...


TOPICS: Astronomy; Science
KEYWORDS: astronomy; bigsplash; brianmay; c2013us10; catalinaskysurvey; catastrophism; comet; cometcatalina; comets; dunce; emiliospedicato; greencomet; impact; louisafrank; louisfrank; notsogreatflood; originofoceans; originoftheoceans; panspermia; patrickhuyghe; queen; retrograde; science; smallcomets; spedicato; thebigsplash; twit; water
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To: SunkenCiv

Maybe it will hit Mecca!


21 posted on 06/04/2005 5:56:06 AM PDT by reg45
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To: ladtx
Crap, June 11, 2085 I've got tickets to a Rangers game that day, just my luck.

That's a long time to wait for a winning season!

;-)

22 posted on 06/04/2005 5:59:16 AM PDT by reg45
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To: SunkenCiv

The new director favors the BDB. The old director did not know what a BDB is. The BDB doesn't have to be based on the Space Shuttle, but at least some of the hardware is still in manufacture, so that will avoid some tooling and training costs.


23 posted on 06/04/2005 10:48:06 AM PDT by RightWhale (It comes down to lack of private property rights)
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To: RightWhale

BDB... "Big D***** Booster"... ?

http://www.cpia.jhu.edu/Acronyms/

Bis(difluoramino)butane


24 posted on 06/04/2005 3:29:01 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv
Big dumb booster.

Wagons, ho!

25 posted on 06/04/2005 3:33:53 PM PDT by RightWhale (It comes down to lack of private property rights)
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To: RightWhale

I think problems will arise if an old design is revived (say, the F-1, the production for which could be restarted), partly because of the mindless pursuit of the new, but also, and mainly, because of the political struggle over where the components would be built. We already know where the Dims stand -- against human spaceflight, particularly a return to the Moon. Von Braun's model was a step by step approach: learn how to do each job needed to get to (ultimately) Mars. First, get to space and reenter; then orbit; then spacewalking; then rendezvous; then docking; then a trip around the Moon and back; then test the landing vehicle and safe return; then land, plant the flag, grab some rocks, and safe return; then repeat the process a number of times.

All of that will also have to be redone, probably in simulators using CGI.

Von Braun's human mission to Mars would have involved twelve Saturn V launches to assemble in LEO and send it on its way. Of course, it would have merely begun the process of getting there. The first mission might have been crewed, but would have been an orbit-and-return. Then again, perhaps Apollo missions (including 18 through 21, which were scrapped) would have been judged to have provided a sufficient base of experience for an immediate landing mission.

Saturn 5 Blueprints Safely in Storage
space.com | 13 March 2000 | By Michael Paine
Posted on 01/08/2004 2:20:33 PM PST by Dead Dog
http://www.freerepublic.com/focus/f-news/1054183/posts


26 posted on 06/04/2005 8:01:18 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv

NASA has the concept of an earth-Mars shuttle system, which might consist of more than one shuttle vehicle continually going back and forth, as well as an earth-moon shuttle system. The idea of a transportation infrastructure would be intended for longterm discovery and development rather than a few one-off missions. That is, there would be regular transportation to and from the moon and Mars from now on. While it would cost something to set up, it should be cost-effective in the long run. Something similar would be done with respect to the Asteroid Belt by the private sector if asteroid mining is ever allowed.


27 posted on 06/05/2005 9:15:23 AM PDT by RightWhale (We're trying to get rid of foreign oil, not find something more efficient or cheaper)
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that page is still gone, and the cache I linked appears to have expired. There is another cached version (which I'm about to post).
Google

28 posted on 06/05/2005 4:04:45 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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Three objects with Torino 1 on this list:

http://neo.jpl.nasa.gov/risk/


29 posted on 06/05/2005 4:05:36 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: RightWhale

Asteroid mining might be better done with NEOs, rather than all the way out to the asteroid belt.


30 posted on 06/05/2005 4:06:38 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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Comet Catalina (P/2005 JQ5) Impact Risk (cached version)
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NASA Logo    + View the NASA Portal  
Near Earth Object Program
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NEO Basics Search Programs Discovery Statistics Space Missions News Frequently Asked Questions
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Orbit Diagrams Orbit Elements Close Approaches Impact Risk Images Related LInks
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Back to main Impact Risk Page.

Comet Catalina (P/2005 JQ5)
Earth Impact Risk Summary
Torino Scale (maximum) 0
Palermo Scale (maximum) -4.65
Palermo Scale (cumulative) -4.65
Impact Probability (cumulative) 8.1e-09
Number of Potential Impacts 1
Vimpact 19.95 km/s
Vinfinity 16.55 km/s
H 17.7
Diameter 0.980 km
Mass 1.3e+12 kg
Energy 6.0e+04 MT
all above are mean values
weighted by impact probability
Analysis based on
371 observations spanning 23.870 days
(2005-May-06.27858 to 2005-May-30.14837)
Orbit diagram and elements available here.

These results were computed on May 31, 2005
Comet Catalina (P/2005 JQ5)
Earth Impact Table
Date Distance Width Sigma
Impact
Sigma
LOV
Stretch
LOV
Impact
Probability
Impact
Energy
Palermo
Scale
Torino
Scale
YYYY-MM-DD.DD (rEarth) (rEarth)     (rEarth)   (MT)    
2085-06-11.90  0.06   4.52e-02   0.000   -3.92000   4.54e+04   8.1e-09   6.02e+04   -4.65   0 

Summary Table Description

The Summary Table includes basic information about the hazard for this object. The maximum Torino and Palermo Scale values are listed, as well as the number of tabulated potential impacts and their corresponding cumulative Palermo Scale value and cumulative impact probability. The observation set used for the analysis is also listed. Certain parameter values depend upon the specific impact event in question, but they change little among the various table entries. For this reason we tabulate only mean values for these parameters:
  • Vimpact - Velocity at atmospheric entry.
  • Vinfinity - Relative velocity at atmospheric entry neglecting the acceleration caused by the Earth's gravity field, often called the hyperbolic excess velocity. (Vinfinity2 = Vimpact2 - Vescape2, where Vescape = ~11.2 km/s is the Earth escape velocity.)
  • H - Absolute Magnitude, a measure of the intrinsic brightness of the object.
  • Diameter - This is an estimate, based on the absolute magnitude, and assuming a uniform spherical body with visual albedo pV = 0.154. Since the albedo is rarely well determined the diameter estimate should be considered quite rough, but in most cases will be accurate to within a factor of two.
  • Mass - This estimate assumes a uniform spherical body with the computed diameter and a mass density of 2.6 g/cm3. The mass estimate is somewhat more rough than the diameter estimate, but generally will be accurate to within a factor of three.
  • Energy - The kinetic energy at impact: 0.5 * Mass * Vimpact2. Measured in Megatons of TNT.

Impact Table Legend

See our Introduction for a more extensive explanation of these terms.

Date
The calendar date (UTC) of the potential impact.

Distance
The minimum distance on the target plane (scaled b-plane) from the LOV to the geocenter, measured in Earth radii. For these purposes the radius of the Earth, 6420 km, includes some allowance for the thickness of the atmosphere.

Width
The one-sigma semi-width of the LOV uncertainty region, measured in Earth radii.

Sigma Impact
The lateral distance in sigmas from the LOV to the Earth's atmosphere. Zero indicates that the LOV intersects the Earth. It is computed from (Distance - 1)/Width.

Sigma LOV
The coordinate along the Line Of Variations (LOV). This value is a measure of how well the impacting orbit fits the available observations. Zero indicates the best-fitting, central (nominal) orbit and the further from zero, the less likely the event: Roughly 99% of all the uncertainty region lies between -3 and +3. Sentry explores out to Sigma LOV = +/-5.

Stretch LOV
The stretching is the semimajor axis of the local linear uncertainty region. It describes how fast one moves across the target plane as Sigma LOV changes, and is measured in Earth radii per sigma. The local probability density varies inversely with the stretching, and thus larger stretching values will generally lead to lower impact probabilities.

Impact Probability
The probability that the tabulated impact will occur. The probability computation is complex and depends on a number of assumptions that are difficult to verify. For these reasons the stated probability can easily be inaccurate by a factor of a few, and occasionally by a factor of ten or more.

Impact Energy
The kinetic energy at impact, based upon the computed absolute magnitude and impact velocity for the particular case, and computed in accordance with the guidelines stated for the Palermo Technical Scale. Uncertainty in this value is dominated by mass uncertainty and the stated value will generally be good to within a factor of three.

Palermo Scale
The hazard rating according to the Palermo Technical Impact Hazard Scale, based on the tabulated impact date, impact probability and impact energy.

Torino Scale
The hazard rating according to the Torino Impact Hazard Scale, based on the tabulated impact probability and impact energy.

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FIRST GOV   NASA Home Page Site Manager: Don Yeomans
Webmaster: Ron Baalke
Last Updated:
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31 posted on 06/05/2005 4:13:32 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv

Not much to choose from with NEOs. Asteroid Belt has all three kinds.


32 posted on 06/05/2005 4:20:40 PM PDT by RightWhale (We're trying to get rid of foreign oil, not find something more efficient or cheaper)
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Ah ha. Here's the blankity blank URL. The NEO JPL NASA people added "P". I guess that makes the ice melt faster or somethin'.

http://neo.jpl.nasa.gov/risk/p2005jq5.html


33 posted on 06/05/2005 8:25:16 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: RightWhale

http://www.house.gov/science/press/109/109-78.htm

NOAA, NASA BILLS SAIL THROUGH COMMITTEE

WASHINGTON, D.C., May 17, 2005

H.R. 1022, also introduced by Rep. Rohrabacher, would establish a program within NASA to detect, track, catalogue, and characterize the physical properties of near-Earth asteroids and comets equal to or greater than 100 meters in diameter in order to assess the threat of Earth being struck by such near-Earth objects.  The bill would authorize appropriations for the program of $20 million for each of fiscal years 2006 through 2007.

Rep. Rohrabacher said, "The potential catastrophe of an asteroid hitting Earth should no longer be ignored. We need to know what is out there. Accounts of asteroids passing close to Earth with almost no prior warning should be enough to get our attention. The first step is to assess the threat. Given the vast number of asteroids and comets that inhabit the Earth's neighborhood, greater efforts for tracking and monitoring these objects are critical. This bill would direct NASA to expand their current program to track and detect potential threats and would provide a funding authorization. Any threat that would wreak havoc on or world should be studied and prevented if possible. We have the technology, we need the direction – this bill provides that."


34 posted on 06/05/2005 8:30:58 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv

The threat has been assessed for years. When will hardware be placed in deep space so something may actually be done?


35 posted on 06/06/2005 8:51:43 AM PDT by RightWhale (Final notice)
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To: RightWhale

Too easy to weaponize.

That URL I posted in message 33 is gone now. This is annoying.


36 posted on 06/08/2005 8:56:33 AM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv

They are going to have 1000s of tungsten telephone poles up there anyway. No need to worry.


37 posted on 06/08/2005 12:17:17 PM PDT by RightWhale
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To: RightWhale

NEO Earth Close Approaches
http://neo.jpl.nasa.gov/ca/

NEOs Removed from Impact Risk Tables
http://neo.jpl.nasa.gov/risk/removed.html


38 posted on 06/10/2005 1:41:08 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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everyone could use a laugh, right?

Huge asteroid to fly past Earth (Toutatis hoax - how and why)
space.com | 04/09/29
Posted on 09/29/2004 5:00:09 AM PDT by Truth666
http://www.freerepublic.com/focus/f-chat/1230167/posts


39 posted on 06/10/2005 1:42:16 PM PDT by SunkenCiv (FR profiled updated Tuesday, May 10, 2005. Fewer graphics, faster loading.)
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To: SunkenCiv
WhenI was designing my asteroid mining business proposal I deliberately ignored earth orbit crossing bodies and assumed all mining would be in the main Asteroid Belt. Two reasons:

1. A lot more material to choose from, and

2. I needed to compute far fewer orbits.

40 posted on 06/10/2005 1:44:38 PM PDT by RightWhale (I know nothing, and less every day)
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