CCNet SPECIAL: THE RACE IN NEO DETECTION IS GEARING UP
QUOTE OF THE DAY
"Have things changed because of the movies? I don't
know," Gehrels says. "I cannot tell that. Things may
have changed because of (1997) XF11. That did bring a
scare or a realization. I think the upshot of that event
was, well, it didn't happen this time, but it could
have, and the next time it could be for real. And that
would penetrate more than anything before in Washington,
D.C." (Tom Gehrels, Phoenix New Times, 24 February 1999)
From Victor Noto <email@example.com>
A feature in the PhoenixNewTimes today which I plan to feature on
my web site Bigrock at http://www.phoenixat.com/~vnn2/bigrock.htm
may be of interest to your readers on CCNET about the status of
asteroid hunting in the US.
From The Phoenix New Times, 24 February 1999
ARIZONA ASTEROID HUNTERS WERE POISED TO SAVE THE EARTH FROM
ARMAGEDDON. THEN A SECRET AIR FORCE PROJECT TOOK OVER.
In Deep Impact and Armageddon, last year's two Hollywood fantasies
about asteroid-caused extinction, it's Americans who take the lead
to save the rest of the planet from catastrophe.
In real life, the people who've embraced the greatest responsibility
for saving Earth hail from a more specific location.
Arizona scientists have been among the most important figures
publicizing the dangers of asteroid collision, searching for the
next doomsday rock, and planning ways to save the Earth from a
planetoid heading its way.
Last year, it was an Arizona scientist, James Scotti, who spotted an
object named XF11, a mile-wide boulder that seemed to be headed for a
possible collision with Earth in the year 2028. Scotti works at
Spacewatch, an Arizona project begun nearly 20 years ago by Tom
Gehrels, an astronomer who has labored as earnestly as any scientist to
make the world aware of the threat of asteroid collision.
The day after the dramatic announcement of XF11's discovery, refined
orbit calculations showed that the rock will actually sail past us with
a comfortable million-kilometer margin.
However, if XF11 really were on a course to smack into our planet three
decades from now, world governments would have scrambled to direct it
out of the way. And they would have used plans developed in part by
With the recent explosion of public interest in asteroids, Spacewatch
and other asteroid-hunting programs such as the Lowell Observatory
Near-Earth Object Search (LONEOS) in Flagstaff have enjoyed a sudden
That's quite a change for a branch of science that had been treated as
a kind of poor stepchild by the rest of astronomy. After years of toil
in obscurity and under meager budgets, Arizonans were poised to reap
the benefits of asteroid-mania.
Asteroid hunters had finally hit the big time.
Then, quietly, their labors were stolen from them.
With no fanfare, a secretive operation developed by the Air Force began
dominating the field of asteroid and comet detection. Now, with
equipment developed at costs they won't discuss, a small group of Air
Force technicians using a single, modest-size telescope in New Mexico
has almost completely taken over the responsibility of mapping the
Earth's neighborhood in space.
The Air Force's astounding success is great news for the planet, of
course, and the public can rejoice that the military program scans so
much of the sky night after night. But for Arizona astronomers who had
invested their careers in finding hazardous asteroids, losing out to
Air Force spy satellite engineers has a bittersweet taste.
It will be Air Force technicians, not Arizona astronomers, who will
most likely tell Earthlings when they can expect Armageddon.
They promise not to hold back any secrets.
Tons of creaking metal are on a collision course with a startled
photographer, and if he doesn't scramble out of the way, he might
likely be pulverized.
With a nervous giggle, the photographer grabs his gear and scurries
along the wooden floor to get out of the way of the moving steel
walkway headed right for him.
Meanwhile, Tom Gehrels pushes buttons on a large metal control box at
the Spacewatch telescope housed in a dome on Kitt Peak in southern
Arizona, and seems oblivious that he'd nearly crushed someone by
rotating the telescope into position.
"Every half-hour, I dash up here to move the telescope and check it
with a flashlight," Gehrels narrates in his Dutch accent. "It's pitch
dark. But the telescope cannot hit any of the steel struts of the dome
or that would be the end of the whole project."
Gehrels watches carefully as the telescope -- as tall as a house and
big around as a car -- shifts position, making sure it doesn't go near
various steel gussets holding up the dome. Then he leans over and says
knowingly: "I was watching him, incidentally. I would not have hit him.
I could see that he just got out of the way in time."
"Sorry," he says to the photographer, who shakes it off good-naturedly.
Gehrels seems to enjoy the episode. For several hours, the astronomer
dances around the 79-year-old telescope, moving it into position and
then dashing downstairs into a control room to begin another search for
dim points of light. The slender, flaxen-haired astronomer seems to
relish catching his guests off guard with his dry sense of humor.
Only five years younger than the old telescope, Gehrels defies his age
by nimbly twisting and leaping around the instrument to position it to
explore new swaths of sky. The Spacewatch scope is computerized, but if
it isn't watched closely, it's likely to plow into one of the steel
struts or, as happens a few minutes later, dump its guidance system and
stubbornly refuse to budge. But Gehrels never seems discouraged. He
clearly enjoys coaxing the aging equipment and delights over what pops
up on the computer screens below.
For decades, Gehrels has pursued a branch of astronomy that has, until
recent years, garnered little attention or hoopla. But eventually, with
the efforts of Gehrels and others, his passion -- asteroids and the
threat they pose to Earth -- began to grip the public's imagination.
Then, seemingly overnight, it became all the rage.
As a result, Gehrels has been featured in dozens of articles as The Man
Who Would Save Earth.
"Have things changed because of the movies? I don't know," Gehrels
says. "I cannot tell that. Things may have changed because of
(1997) XF11. That did bring a scare or a realization. I think the
upshot of that event was, well, it didn't happen this time, but it
could have, and the next time it could be for real. And that would
penetrate more than anything before in Washington, D.C."
Since the public -- and Congress -- has become more aware of the threat
posed by asteroids, NASA has increased its funding to programs like
Spacewatch. But for such a high-tech enterprise, Spacewatch makes do
with surprisingly low-tech equipment. That's a trait of asteroid
astronomy, which has endured a second-class status in the study of the
Prestige and dollars have tended to go to scientists trying to answer
the really big questions, such as the age and fate of the universe.
That endeavor requires huge ground-based instruments, as well as the
Hubble Space Telescope, which examine galaxies at the far reaches of
the visible universe.
By comparison, Gehrels and his colleagues have worked in relative
obscurity, using modest equipment, mapping space boulders in the
Earth's cosmic backyard. One of those boulders, however, is on a
collision course with Earth. There's no doubt about it, scientists
say. The only question is how long we have -- 30 years or 30 million?
To answer that question, Gehrels dances around his telescope to make
sure it doesn't run into its own dome, and stares at computer screens
all night, looking for wayward asteroids.
Think of him as the solar system's air traffic controller, monitoring
the flight paths of thousands of objects to make sure none of them has
our name on it.
In the meantime, Gehrels has to put up with a nearly constant parade of
reporters who insist on sitting up all night with him. So many
journalists have made the trek to Kitt Peak to interview him, Gehrels
begins answering questions before they're asked.
Bad reporting, he says, has led to several misconceptions about the
threat asteroids and comets pose to Earth. For one thing, he says, the
public has been misled about the likelihood that life will be wiped out
in the near future by a hurtling planetoid.
It's far more likely than people imagine, he says.
The solar system today is misleadingly calm.
In its early history, the Earth's neighborhood was more like a cosmic
billiards game, with planetoids running into each other with
For proof, just aim a pair of binoculars at the Moon some night.
Pockmarked like a celestial battleground, the airless, lifeless body
bears witness to eons of destruction.
Gradually, large conglomerations of those early planetoids stuck
together, swept up even more material, and were shaped by gravity
to become the planets that we know today. Gravity also ejected some of
the early planetoids, and many were left in a band of material between
the planets Mars and Jupiter known as the Asteroid Belt. In the
meantime, the major planets were occasionally cold-cocked by hurtling
asteroids and comets. One such collision, goes a popular theory, tore
off a huge piece of Earth -- stuff that eventually became the Moon. In
recent times -- the past billion years or so -- the pace of such
collisions has slowed as the solar system has become a more peaceful
place. But the collisions have not stopped.
Traveling in paths around the Sun, some asteroids follow orbits that
take them into the Earth's realm of the solar system but not close
enough to be a hazard. But those orbits can change. The strong
gravitational pull of Jupiter, for example, can influence asteroids and
comets and put them on a new course and a future date with disaster.
Scientists have long known that the Earth was subject to annihilation
in its history. But erosion by wind and water has erased most of
Earth's scars -- Meteor Crater near Winslow is an exception -- and it
was easy to ignore that the planet could take another hit in the
That view eventually changed. And it all began with a discovery not by
astronomers but by a geologist.
In the 1970s, Luis Alvarez and his physicist father, Walter, made a
stunning discovery. Like other geologists, Luis was familiar with a
layer of dark earth, present all over the globe, that scientists used
to mark the boundary between two geologic periods. When he and his
father analyzed the layer, however, they realized that it contained
high concentrations of a rare element, iridium, which is more common in
meteors than it is on Earth. In 1979, Walter proposed to other
scientists that the dark layer suggested the planet had taken a massive
hit by an asteroid. The impact was so huge, the asteroid was pulverized
and its material deposited across the Earth, eventually resulting in
the dark layer.
The Alvarez theory was met with pessimism by astronomers. But another
group of researchers -- paleontologists -- took notice.
The boundary that Luis Alvarez had analyzed happened to mark a period
65 million years ago, precisely the time when nearly all of the
planet's dinosaurs and other large animals had died off in a mass
extinction. Had the impact that laid down the dark layer also
killed off the dinosaurs?
Throughout the 1980s, debate raged over the fate of the dinosaurs. In
the meantime, an Arizona astronomer, Gene Shoemaker, became concerned
with another question. If most life had been wiped out by an asteroid
65 million years ago, what were the chances that another space rock was
on its way for a repeat performance?
Shoemaker, a man who had unlocked the secrets of Meteor Crater, began
to lobby whomever he could that astronomers should be watching the sky
for the next Earth-collider.
One of the first to take up his challenge was Tom Gehrels, who had
already been studying asteroids for their physical properties. In 1989,
Gehrels' Kitt Peak program, Spacewatch, developed new software that
allowed it to search more efficiently not only for the asteroids out
beyond Mars but also those asteroids and comets that came into the
These Near-Earth Objects, or NEOs, can be elusive. Fast-moving and
anywhere from the size of a grain of sand to the size of a city, they
can be exceedingly dim.
The pebble-size ones are of no real concern. Entering the atmosphere at
about 70,000 miles per hour, they burn up from friction. At night, we
see them as meteors, or "shooting stars."
But objects larger than a house make astronomers nervous. A
building-size object carved out Meteor Crater some 40,000 years
ago. The resultant shock wave would have imperiled the people of
Flagstaff, 40 miles away, if the town had existed.
Scientists figure that the entire globe would be in trouble if hit by
an object about a kilometer across or larger. Even people and animals
far from the impact and not killed by a tsunami or rain of ejecta would
eventually feel its effects. In the case of the dinosaur-killer 65
million years ago, scientists theorize that a large impact, perhaps
with an object seven kilometers across that is believed to have struck
near what today is the Yucatán Peninsula, threw so much of the Earth's
crust into the atmosphere that the entire planet was veiled in an
opaque layer of grime. Pitch-dark at the surface for months, most plant
life would have died. For years, the planet would have been gripped in
a nuclear winter.
What are the chances that such a cataclysmic impact will occur in a
human being's rather short lifetime?
About one in 5,000, says Tom Gehrels.
Gehrels estimates that a one-kilometer-size object hits the Earth about
once every 330,000 years. Divide that by the typical lifetime of 66
years, and you get the 1 in 5,000 result.
Those are the same odds that a person will be killed in an auto
Despite those odds, and Spacewatch's increasing ability after 1989 to
find such potentially hazardous objects, scientists still had trouble
convincing the public that it was in danger.
In particular, astronomers had trouble convincing Congress, which
refused NASA requests for funding of Spacewatch and other projects
searching for NEOs.
Then, in 1994, Congress and the rest of the world got a preview of
things to come. Fragments of Comet Shoemaker-Levy 9 plowed into the
planet Jupiter that July and created devastation on Earth-size scales.
One of its discoverers was the same Gene Shoemaker who had years
earlier begun telling scientists to watch out for just such a
cataclysm. (Shoemaker himself met an untimely end in a collision
of another kind. He was killed in an automobile accident in 1997
while on a trip to Australia to inspect impact craters.)
After Shoemaker-Levy 9's amazing show, a duly impressed Congress
approached NASA and ordered that the country's scientists get to work.
Within 20 years, Congress mandated, astronomers should find and plot
the orbits of 90 percent of the objects in the solar system with the
potential to collide with Earth.
Astronomer Brian Skiff says that's when Flagstaff's Lowell Observatory
decided to jump into the game.
With new NASA funding available, Skiff says, Lowell scientists realized
that Spacewatch could be beat in the search for NEOs.
Astronomers face a dilemma when they're looking for "Earth-crossers"
(what astronomers call objects that cross Earth's orbit and could
someday hit us). Do they look deeply at a small piece of sky, or more
superficially at a larger swath? The first method picks up smaller
objects that have a greater chance of hitting us; the second method
picks up more total objects, but misses the smaller ones.
Spacewatch had settled on the first approach, going deep on small
pieces of sky. Lowell decided to develop a telescope that would see
more of the sky and forsake the small objects to go for the big rocks
with the potential of wiping out all life.
Since 1994, Skiff says, Lowell has struggled to develop its LONEOS
system, for Lowell Observatory Near-Earth Object Search, which finally
came online and found its first NEO last summer. But the two Arizona
projects complemented each other well and led the other handful of
NASA-funded programs in the search for potentially hazardous objects.
Between Spacewatch's deep search for small objects and LONEOS's wide
view looking for planet-killers, Arizona had become the place most
responsible for alerting planet Earth. Both programs became swamped
with media requests as reporters and film crews, particularly from
Europe, clamored to interview the scientists searching for Doomsday.
Those requests haven't slowed.
Then, last year, strange rumors began.
By last fall, the buzz in asteroid circles concerned a new program no
one seemed to know much about.
Asteroid hunters spoke of a project working out of a restricted
military base that was all but usurping their field. Its rumored
attributes made astronomers in Arizona sound like a bunch of conspiracy
Secret "black" technology being used by the military to hunt down
asteroids by the thousands . . . superfast imaging cameras capable
of things unimaginable to other astronomers . . . discoveries of Near
Earth Asteroids, main belt asteroids, and comets on a staggering scale,
leaving precious little undiscovered for projects like Spacewatch.
That's when New Times began a long process of getting access to
something called LINEAR, for Lincoln Near-Earth Asteroid Research. The
people who run it, at MIT's Lincoln Laboratory, tried to discourage a
visit; Grant Stokes, who runs the program from Boston, hoped that a
visit to his offices there would prove satisfactory. But he was pressed
to arrange a visit to the installation itself, which is on the White
Sands Missile Range near Socorro, New Mexico.
Two months and three layers of government approval later, Lincoln Lab
agreed to a visit.
After a six-hour drive from Phoenix, the road to LINEAR terminates at
the north entrance of the missile range, just a mile from Trinity Site,
where the first atomic bomb exploded July 16, 1945.
While visitors are interrogated by a humorless guard, they are
greeted by a sign.
(then, in disconcertingly small type)
"You are entering an active explosives test range. Areas are
potentially contaminated with explosive devices. Stay on the roads. Do
not touch or disturb any items. If items are found call the White Sands
police . . ."
Just a few hundred yards away across a high desert landscape (which,
according to the warning, sounded like it concealed a lethal minefield
of unexploded cruise missiles) lay the LINEAR observatory, a squat
sheet metal building with various small observatory domes surrounding
LINEAR operates out of just one of the domes, and the Air Force uses
the rest in a program called Ground-based Electro-Optical Deep Space
Surveillance, or GEODSS, a typically unpronounceable military acronym
for a program that keeps track of the 9,500 manmade objects circling
Earth. From errant astronaut gloves to foreign spy satellites, GEODSS
keeps the Air Force in the know about everything whizzing over American
airspace. The technology to track manmade objects, it turns out, is
equally effective at detecting celestial ones.
Three men waited to give a tour of the building. Grant Stokes had flown
in from Boston, Eric Pearce was the on-site astronomer who managed the
facility, and Roger Sudbury was a Lincoln Laboratory public relations
man whose main job seemed to be to follow the other two around
nervously to make sure they didn't say something they shouldn't.
Stokes, in contrast, was friendly, intelligent, and positively beaming.
And he had every reason to be. His program in just a few months has
revolutionized the field of asteroid detection.
He led the group to a conference room to talk about how his project --
using a telescope just slightly bigger than Gehrels' on Kitt Peak --
had leapfrogged past all the others. On the way, he passed a notice
pinned to a bulletin board in the hallway:
"To maintain our lead, secrecy is essential. The intelligence threat to
the U.S. has not disappeared. Even some of our allies have organized
intelligence operations dedicated to acquiring U.S. technology.
Technology protection is the best countermeasure. Let's all do our part
to prevent future leaks."
Stokes, however, seemed happy to give up LINEAR's secrets. He opened up
a black plastic case and showed off the mysterious equipment that
astronomers had been spreading rumors about. It was a single, four-inch
silicon wafer, the sort manufacturers like Intel carve up into small
chips for computers. But this wafer was different.
The entire thing was just one chip.
It was the LINEAR charge-coupled device or CCD, the heart of a camera
that rides on a telescope. Like a proud owner talking about the cool
equipment on his cherry show car, Stokes pointed out the features of
his souped-up machine.
A CCD chip is a computer's eye on the world. Small CCD chips power
camcorders and digital cameras; their sensitive electronics record an
image on picture elements (commonly called "pixels") that are then read
into a computer. Camcorder CCDs make do with a few hundred thousand
pixels; the LINEAR chip has five million.
Like other CCDs used in observatories around the world, the LINEAR chip
is especially sensitive and can soak up starlight quickly. But LINEAR
leaves those other chips in the dust when it comes time to download its
image into Air Force computers.
After soaking up an image of starry sky, other astronomers have to
close a shutter and can wait up to two minutes for the image to read
out of a large CCD, column by pixel column.
The LINEAR CCD, by contrast, downloads its five million pixels in
a few milliseconds.
While astronomers in Arizona methodically patrol smaller swaths of sky,
the LINEAR chip pops off thousands of exposures each night mounted on a
telescope built for speed.
Pearce showed off the project's one-meter telescope housed in a small
dome outside the LINEAR shack. He goes out to the scope each working
evening to take off a cloth cover, but unlike Gehrels at Spacewatch,
the rest of the night Pearce stays inside the heated building as the
scope runs completely on its own. There's no need to watch the scope
for fear that it might run into something.
Taking rapid snapshots in a stairstep pattern, the LINEAR scope covers
so much sky in a single night, it has time to go back and image
previous areas five separate times.
Then, inside the control room, Frank Shelly and his software take over.
Shelly demonstrated how the five separate images of a piece of sky are
layered on top of each other by powerful computers. With the push of a
button, the software seems to gobble up the images in a pulsing display
that devoured the thousands of stars on the screen. Suddenly, the only
thing showing are the handful of objects the computer had decided were
asteroids. Everything else had been subtracted..
Even in a field taken in the Milky Way -- where other astronomers fear
to tread because of the dense concentration of stars -- the LINEAR
computers gobbled up the fixed stars and found asteroids hiding amid
"If you're willing to take five frames, the software has a very good
performance with respect to probability of discovery and a very low
false-alarm rate," said Stokes in his typically understated, technical
way. "The Minor Planet Center tells us that when we sweep through an
area we find everything we're supposed to find. Everything they know
about we find and plus all the other stuff they don't know about."
The results have been astonishing.
Since LINEAR went online at full speed last March, the project has
swamped the Minor Planet Center -- the world's clearinghouse of
asteroid information at Harvard University -- with new discoveries.
Of the 147 total Near-Earth Objects found in all observatories between
March and November, LINEAR discovered 102.
Of those one kilometer and larger -- the size considered large enough
to cause mass extinctions in an impact with Earth -- LINEAR discovered
26 of the 38 total.
Out of 28 comets discovered in the same period, LINEAR had its name
attached to 13.
Before last March, the Minor Planet Center had received about 10,000
observations every month from scientists all over the world. In
September 1998, a particularly clear month in New Mexico, LINEAR alone
sent the MPC more than 160,000 observations.
By January, overworked orbit calculators at the Minor Planet Center had
given designations to 19,200 new asteroids discovered by LINEAR in only
10 months of operation.
Spacewatch, by contrast, has 25,000 new asteroids to its name. But
that's after 10 years of full-blown operation.
Harvard's Minor Planet Center "is going to have to get some new
computers," Stokes says with a satisfied grin.
Stokes has reason to be smug. Two years ago, he says, he began visiting
astronomical conferences to tell others about the LINEAR concept, and
he was surprised at the response.
"It was met, I think, with an awful lot of skepticism as to whether we
could really pull it off," he says. "I think now that we're up and
running hard, where we're scooping up enough in the sky all by
ourselves, at some point I believe we will want to, you know,
coordinate searches between the astronomers. We're looking at figuring
out ways to do that. That's clearly in the future."
Did he mean the LINEAR people would give others access to that
expensive Air Force technology?
"I think there are a lot of people who would like to get that chip," he
said with another grin.
Asked what the chip had cost to develop, Stokes said it would be
difficult to isolate. He and other scientists at Lincoln Laboratory had
produced the chip as they sought ways to help the Air Force with
projects such as Space-Based Space Surveillance -- in other words,
satellites spying on satellites. It's Stokes' main gig, one he got
after studying for a doctorate in physics at Princeton, where he hunted
for pulsars -- degenerate stars spinning at incredible speeds -- with a
radio telescope. After grad school, Stokes says he got away from
astronomy and dove into the field of surveillance.
Eventually, he says, it dawned on him that the surveillance equipment
they were developing at Lincoln Laboratory could be used to find
near-earth asteroids. The Air Force accepted the LINEAR proposal and
has spent about a million dollars in the past three years to make the
project a reality, Stokes says.
Stokes won't say what the souped-up chip cost to develop, but one
non-LINEAR astronomer tells New Times he believes the Air Force spent
between $150 million and $200 million to build it. That's in comparison
to projects like Lowell's LONEOS, which hasn't spent a million dollars
in its entire history.
Lowell's Brian Skiff scoffs at the estimate and says he doesn't think
the military spent that much.
But Skiff does acknowledge the superiority of the Air Force technology.
"In five years, LINEAR will have everything in the solar system mapped
down to the crumbs," he says enviously.
Arizona asteroid hunters had hoped they might save Earth from
extinction by asteroid. Now they're scrambling to save themselves from
extinction by LINEAR.
Tom Gehrels was asked what he thought about the impact of LINEAR, and
he answered only by saying that LINEAR's contribution was welcome.
But Lowell's Brian Skiff in particular wonders what's the point of
trying to compete with the military's amazing program.
"I thought I did really well last night," he says, sounding dejected.
"I detected 900 asteroids at the opposition point [the portion of sky
opposite the Sun]. LINEAR no doubt was there three nights ago and saw
Skiff says LONEOS now has to look forward to a short period when
the monsoon season leaves Arizona and lingers in New Mexico,
keeping LINEAR's observations low. "We're occasionally picking up
things that slip through their net, and ultimately the science
gets done, whether by us or somebody else. Then again, it's a bit
disheartening to struggle for several years to get a project
rolling, only to have somebody come along in a balloon and usurp
your work because of a tremendous technical advantage."
Skiff says that Lowell will be getting new equipment, however, and
he's heard that the Air Force will begin looking deeper into
"If LINEAR goes deeper, they'll cover less sky. With a new camera,
we'll cover more sky and the projects will become more
complementary. So it's not totally hopeless," he says.
Both Spacewatch and LONEOS astronomers emphasize that they do more
than just look for asteroids heading for a doomsday with Earth.
Spacewatch has always been as interested in the physical
characteristics of the asteroids themselves and describing
asteroid families. LONEOS, meanwhile, contributes to a University
of Washington program to track down undiscovered variable
But those projects aren't what bring journalists in flocks to Kitt
Peak and Lowell Observatory. The glory is in discovering hazardous
objects. And increasingly, LINEAR has all but taken over that
Robert McMillan, Spacewatch's principal investigator, downplays
the impact LINEAR has had on his team. "We're really a scientific
investigation. We're not just looking for things that threaten the
Earth, but we're trying to figure out distribution of the
asteroids and their characteristics. Spacewatch is a much more
comprehensive scientific investigation. As long as they [LINEAR]
don't pretend to be scientists (sic), I have no problem with it at
all. They're obviously doing it better than the other groups. But
maybe not for long," he says.
It's hard not to perceive some resentment in the way Skiff and
McMillan describe LINEAR. After all, the Arizona scientists are
astronomers who study asteroids as interesting solar system
denizens. The LINEAR workers, however, are Air Force tech-heads
with fancy electronics who couldn't care less what it is they're
actually tracking down (sic).
LINEAR's Grant Stokes doesn't flinch at the description.
"Am I a real astronomer? Maybe," he says. "I think asteroids
are quite interesting, but the way we got into this is asteroids as
targets, not asteroids as fundamentally interesting. . . . In fact,
asteroids were just like everything else; you could make them look
like everything else we track. We're getting an education. The
astronomers are experts in asteroids and work hard to build
systems that find them. We have systems that find them and we're
working toward understanding asteroids."
What the LINEAR scientists discover seems less interesting to them
than to astronomers such as Spacewatch's Tom Gehrels, who marvels
over dim comets that he directs a 79-year-old telescope to view.
Last fall, a comet discovered in LINEAR's massive survey labeled
1998 U5 captured the attention of many astronomers when it
suddenly flared in brightness. Amateur astronomers around the
country kept their eyes on it. Did the LINEAR scientists follow
the progress of their fascinating find?
"Not in any real sense," Stokes answered. "I mean, we certainly
try to keep track of the interesting things that we find. We find,
quite frankly, so many of them that any individual one you ask me
about I'll give you a blank look."
Despite its relative uninterest in what it finds, the LINEAR
project now has an awesome responsibility. Given its seizure of
the asteroid-detection field, it's likely that the next asteroid to
threaten the planet will be found by LINEAR. In other words, it's
the Air Force that will tell us about the doomsday rock.
Imagine what Art Bell and the conspiracy crowd will do with that
Stokes assures New Times that all of LINEAR's observations are
sent directly to the Minor Planet Center. If anything, he says, it
will be the MPC that will determine that one of the rocks found by
LINEAR is on a collision course with Earth.
"They'll tell us about it, not the other way around," he says.
While Spacewatch and LONEOS hurry to catch up to LINEAR and its
awesome chip, NASA has decided to make things even tougher on the
LINEAR recently applied for, and got, NASA funding to add to its
Air Force money. What will it do with the added cash?
Start a second LINEAR, says Grant Stokes. It's a fairly simple
matter of strapping one of the superchips to another of the
facility's telescopes and should be done by this spring, he adds.
Earth gains even more protection, and the other programs fall even
Does LINEAR's success threaten the continued funding of other
programs by NASA?
"We know that these groups move in and out," says NASA's Tom
Morgan. "You really can't predict it. That's why we give them some
time. In the fullness of time, they will be due a full proposal,
and they will be evaluated by their peers."
Funded in three-year cycles, LONEOS and Spacewatch have some time
to produce results before they reapply for NASA money. LONEOS
operates entirely on the space agency's funds. Spacewatch,
meanwhile, relies on NASA money for about a third of its budget.
James Scotti says Spacewatch is wasting no time. "I think it
pushes everybody in the business to do what we had all planned to
do anyway. For a while we were the big guys on the block, taking
over from the Shoemakers at Palomar."
Scotti became an overnight celebrity when it was announced last
year that he had found a mile-wide object that could wipe us out
in 30 years.
Scotti's find, (1997) XF11, will actually miss Earth in 2028 with
plenty of room to spare. But for a day, at least, Scotti seemed to
have been the man who had pegged Judgment Day.
Now, after being leapfrogged by the Air Force, Scotti says
Spacewatch is determined to catch up to LINEAR. New cameras
mounted on Spacewatch's old telescope and the completion of a
newer, larger telescope as well as new software should begin
bridging the gap between the two systems.
But even if Spacewatch and LONEOS can upgrade their equipment and
catch the Air Force techies, isn't there a built-in obsolesence to
their searches? Won't they eventually know the location, speed and
direction of every one-kilometer space boulder with a chance of
"We'll certainly solve the problem at some point. But what about
the half-kilometer objects? One of those could kill millions. It
all depends on how far down you want to draw the line of what's
dangerous," Scotti says. "You're trying to put a complete picture
of what the solar system looks like. And it's difficult,
particularly when you go into the outer solar system where these
things are so faint. Even all of the surveys we have in mind are
not going to find these very small objects."
There's a good possibility that after several more years of
searching -- and several million dollars spent -- astronomers will
find that Earth is not likely to be hit by a significant impact
for centuries or even thousands of years. Along with a global
sense of relief, will asteroid hunters experience a sense of
frustration? Would mass death vindicate someone like Tom Gehrels,
who has worked for so many years to make the planet take the
asteroid threat seriously?
"There was a wish," Gehrels says, "during the Cold War." Asked to
elaborate, Gehrels admits that he had yearned at one time that a
menacing asteroid might be found, hoping that it would force
nations to cooperate and avert disaster.
In the meantime, until LINEAR steals it away, press attention
seems as everpresent in Gehrels' life. He admits that it's been
"maybe a bit of each, a little annoying, a little satisfying."
If he found reporters to be more trouble than they were worth,
however, Gehrels was only getting the attention that he richly
It seemed a shame he was finally getting that attention just as he
was being made obsolete.
© 1998 NewTimes, Inc. All rights reserved.
Contact Tony Ortega at his online address:
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