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assing can push a et about； making an estimate of its orbit even harder。 Furthermore； with the long axis running from the northwest to the southeast； who could tell？ It may skid across our atmosphere and disappear south； thought F'lessan hopefully。
Yet another working window opened； labeled SEARCHING。 Images of what F'lessan knew to be Pernese space flashed past； the streaking orbits of some of the minor planets against the background of northern hemisphere stars。
〃What's all that about？〃 Stinar asked Erragon who was blinking at the rapidly altering display。
〃I'd hazard the guess that it's searching for any old images of the et。 It is possible； you know；〃 Erragon went on； frowning at the speed of the search pattern； 〃that the et originated in the Oort cloud。〃 His grin was forced。 〃It might even have been seen by our Ancestors。〃
〃Really？〃
Erragon sighed； flicking his attention to some of the other sidebars。 〃We have a lot of material to review； you know。 Just for our home system。 Ah； yes；〃 and he pointed back to the search。 〃The material we're seeing was released from the et two to three weeks ago。 Here we go；〃 he added； intent on the newest sidebar readings。
Encounter Analysis Estimated Perigee in 1800 seconds Projected Perigee Distance 16km； error ± 296km Encounter Velocity 58。48km/sec ± 0。18km/sec Probability of Impact 48。9％
Probability of Atmospheric Breakup （Airburst） 1。3％ Impact Error Ellipse 3698 times 592km Location and Orientation of Ellipse 9° north； 18° east； Major Axis bearing 130°
At that point； Erragon visibly tensed； leaning slightly forward on the balls of his feet in an attitude that confirmed F'lessan's bad feelings about the alteration in probability of impact。 He wasn't certain that the error ellipse of impact was reassuring。 Unless the et suddenly pulled itself up in an escape parabola。 Estimate to Perigee decreasing： 1500 seconds； or 25 minutes； F'lessan told himself。 He also didn't like standing around； watching； in a room full of people who didn't seem to realize what could happen。 The tension was palpable but everyone was so focused on the screen； too scared to ask questions or to break into the concentration of Stinar or Erragon。
New figures at 1200 seconds； from the Yoko's synchronic orbit over Pern； gave coordinates of Range 71377km； Yoko latitude 45。IN； Yoko longitude 118。4m。 The magnitude was …5； which was bright enough and getting brighter and the fireball was suddenly moving a degree every minute。 He stepped right beside Stinar and Erragon。
〃Where will it impact？〃 F'lessan murmured for their ears only。
〃We still don't know that it will；〃 Stinar said softly； restlessly shifting his feet； turning his head sideways so that his words just reached F'lessan。
〃There's a three…hundred…kilometer range error；〃 Erragon said as if that was significant。
〃Where？〃 Stinar demanded。
〃Right now； the range extends along the farther Eastern Island Ring。〃
〃On the islands themselves； or in the sea？〃
Stinar took the hand…control unit from his pocket and punched in a mand。 The monitor opened a small window in the right corner； while the Probability Impact percentage rose steadily into the 50's and the error ellipse…that narrow band along the far islands to which the fireball was inexorably aimed…got smaller。 The new window showed the Eastern Sea as it must be seen from Yoko； and the scattered islands of both Eastern Rings。 A wide band was superimposed over the upper islands。
〃Looks more like the islands；〃 Stinar said with a little shrug。
F'lessan knew that the islands were uninhabited； too far out in the Eastern Ring Sea to be attractive for anyone； even Tone； to hold； except whichever island currently housed the Abominator exiles…and no one but N'ton knew where that was。
〃I don't like that；〃 Erragon said； stiffening。
〃Why？〃
〃Those islands are all volcanic。 An impact on them might trigger eruptions all along that chain；〃 he said； pointing。
〃Then we'll just hope it falls in the sea；〃 Stinar said with a slightly nervous laugh。
〃That will produce other hazards；〃 Erragon said solemnly。
F'lessan caught his breath。 He'd seen volcanoes erupt； the one Piemur had discovered off the westernmost tip of Southern Hold blew up periodically； sending clouds of gray ash to blot the sun and stifle even the rich tropical vegetation。 The one in the near Eastern Ring； which the Ancients had called Young Mountain； liked to send immense boulders skyward and great lava flows down its side； spinning burning chunks onto its neighbors。 The islands that the et was heading for were much larger and he shuddered at the thought of all of them being active。 They would cause tidal waves； which could have a disastrous effect on coastal areas…like Monaco。
〃It could still just graze；〃 Erragon murmured to Stinar； in a tone that gave F'lessan no confidence in that possibility at all。
He glanced up at the legend； numbers whirring into new configurations all the time； as Yoko telemetry updated them。
〃It's only got a few minutes to change course；〃 F'lessan said。
Erragon glanced at him； blinking； as if he'd forgotten the bronze rider's presence。 〃Did you know your Weyrleaders are in the conference room with Master Wansor？〃
Lessa and F'lar were also here？ When…and why…had they arrived？ Obscurely he was glad they had； especially the way this event was proceeding。
〃No； but I'd rather be in here and know the worst；〃 F'lessan said； watching Erragon's shoulders twitch in startled reaction to the last word。 〃Where will it hit us？〃
〃We don't know yet；〃 but F'lessan saw Erragon's eye flick to the Impact Probability； which flickered onto 60 percent。
All three men caught their breath as the percentage jumped in a matter of seconds to 100 percent。
〃That's still a consequence of the grazing impact；〃 Erragon said but F'lessan didn't think he believed that。 〃The ellipse is shrinking。 Can you adjust Yoko's visuals？〃
On the map in the right…hand corner； the figures flickered in latitude and longitude； following the last downward plunge of the et。 Filling that screen at maximum magnification； the tuberlike shape of the et nucleus showed geysers and jets blowing into space； chunks breaking off； floating slowly away。 F'lessan was amazed since he knew the speed at which the et was traveling and that eerie； almost dignified； breakup of its parts was like a Gather dance。
〃It's going to miss。。。 〃 Stinar whispered； unconsciously pushing both hands in a deflecting motion。
〃Just a few more degrees。。。 〃 Erragon； too； was taut as if； by exerting sufficient willpower； he could shift the plummeting fireball south and east。
〃It's got to be far enough away。。。 〃 F'lessan was adding his tension in an unconscious effort to affect a descent that no effort could now alter。
F'lessan found himself squinting at the sudden brightness of the picture…the brightness of sunlit sea or the et。 The magnitude of its dust trail now registered an eye…blinding intensity of …9！
A new message imposed itself prominently： 120 seconds to perigee…705 seconds to impact。
The monitor altered abruptly； darkening； and F'lessan