PLEASE NOTE:
*
LETTERS TO THE MODERATOR, 4 March 1999
--------------------------------------
(1) STRAIGHT FROM THE HORSES MOUTH:
NASA THUS FAR HAS FAILED TO MEET SHOEMAKER
RECOMMENDATIONS
David J. Johnson <starman@mail.fwi.com>
(2) KUIPER BELT MEMBERS AND OPIK'S EQUATIONS
Bob Kobres <bkobres@arches.uga.edu>
(3) IMPACT POLITICS
Jim Himer,Sun Canada National HPC SE <James.Himer@Canada.Sun.COM>
(4) CLIMATIC CYCLES
Joel Gunn <jdgunn3@mindspring.com>
==================
(1) STRAIGHT FROM THE HORSES MOUTH:
NASA THUS FAR HAS FAILED TO MEET SHOEMAKER
RECOMMENDATIONS
From David J. Johnson <starman@mail.fwi.com>
Dear Benny,
Received the following letter from the U.S. House of
Representataives
Committee on Science, with regards to my request for information
on NEO
resesearch funding, or the lack thereof.
Regards,
David Johnson
--------------
U.S.Committee of Science
http://www.house.gov/science/welcome.htm
Letter Date: 2/19/99
From: F. James Sensenbrenner, Jr., Chairman
U.S. House of
Representatives
Committee on Science
Re: NEO Research Funding
Dear Dr. Johnson:
Thank you very much for your letter concerning research into
Near-Earth
objects (NEOs) and strategies to avoid collisions with the Earth.
This
is a very important issue, especially in light of recent
scientific
theories linking the Permo-Triassic extinction of dinosaurs 65
million
years ago with the impact of an asteroid near the Yucatan
Peninsula.
On May 21, 1998 the Science Committee's Subcommittee on Space and
Aeronautics held a hearing with leading scientist, aerospace
experts
and a NASA official to discuss the cataloguing of near Earth
objects
and NASA's funding of this effort. Concerns were raised that NASA
has
thus far failed to meet the recommendations of the Shoemaker Near
Earth
Objects Survey Working Group, a coalition formed in June 1995 to
investigate the NEO cataloguing process. Like you, we are
concerned
that appropriate funding has not been allocated to the
cataloguing
process thus far.
In response to your concern regarding defense strategies, until
1997,
technology was being developed which could lead to a Department
of
Defense capability to intercept asteroids before they strike the
Earth.
This project, called Clementime 2, was line item Vetoed by
President
Clinton in 1997.
Again, thank you for you interest in these issues.
Sincerely,
F. James Sensenbrenner, Jr.
Chairman
================
(2) KUIPER BELT MEMBERS AND OPIK'S EQUATIONS
From Bob Kobres <bkobres@arches.uga.edu>
Kuiper belt members seem a likely source of material for many of
the
more severe episodes of Earth's accretion history, as these
objects
tend to be large and are likely to have greater mass density than
comet
nuclei that formed far from the Sun in the Oort cloud. The orbits
of
objects from this region of our solar system are subject to the
gravitational influence of the large outer planets, which can in
effect
hand these planetesimals off to one another, sometimes bringing
one of
these monsters into the inner solar system with an inclination
close to
the ecliptic. As just one 200 or so kilometer across
Earth-orbit-crossing Kuiper belt born beast, losing much of its
integrity due to approaching the Sun, could yield thousands of
smaller
objects, this family of objects is apt to be a major episodic
contributor to the NEO population.
An excellent web-site devoted to the study of these objects is
available at this URL: http://www.boulder.swri.edu/ekonews/
Among the references to be found there is a 1997 paper by Levison
and
Duncan (From the Kuiper Belt to Jupiter-Family Comets: The
Spatial
Distribution of Ecliptic Comets, ICARUS 127, 13-32) that ends
with this
paragraph:
"We have directly measured the impact rates with the giant
planets in
our simulations. In addition, we have estimated the impact rates
with
the terrestrial planets using Opik's equations. These rates
are given
in Table I. We find that an ecliptic comet will impact Jupiter
once
every 400 years. The impact interval on the Earth is estimated to
be 13
Myr."
This brings to mind a little blurb posted recently on the CCNet
(3/3/99):
> MY GRANDFATHER PREDICTED IMPACT HAZARD 70 YEARS AGO:
> 'INVEST TO AVERT ARMAGEDDON', LEMBIT OPIK (MP) URGES
GOVERNMENT
> The earth is due to be struck by a giant asteroid capable of
wiping
> out the entire human race, a Lib Dem MP has warned. Lembit
Opik is
> urging the government to invest £1m a year in tracking
space rocks to
> avert catastrophe.
> He told BBC News Online: "I'm calling on the government
to take
> seriously the prospect of asteroid or cometary impact with
the earth.
> "Now that's got a pretty high giggle factor, it makes
me sound like
> one of those millennium soothsayers, a Nostradamus of
Parliament, but
> actually it's a very serious threat. We know that the
dinosaurs were
> extinguished by a very big global killer that hit us about
65 million
> years ago and we're due for another one now."
Now let's see……….. If we divide 65 million by 13
million and get a
remainder we're safe, Right?…….OOPS! Maybe
someone should query Lembit
about the details of what E.J. passed along to him.
;^)
http://web.arm.ac.uk/history/opik.html
Bugging Y2K doomsayers.
bobk
================
(3) IMPACT POLITICS
From Jim Himer,Sun Canada National HPC SE <James.Himer@Canada.Sun.COM>
Of course funding related to finding NEOs is one thing. Funding
set aside to do something about NEOs is another. And both these
pragmas are inter-related.
Detecting NEOs far away may be costly (would need to be all-sky
to catch statistical rogues, and geographically distributed to
avoid stations being weathered out) but the time it buys perhaps
makes the solution to take action on them tractable. On the
other
hand, scaling down any search may make doing something about the
encroaching disaster difficult perhaps even impossible (I mean
do necessary launch vehicles even exist today).
Yes, yes, cost is relative -- after all what cost should one put
on
a city, country, or humanity. And I think the relative cost
com-
parison has already made this thread before (e.g. how much the US
spends on cosmetics annually).
As for the politics -- should any one country, or countries, take
on this savior responsibility? Or should it be a
sufficiently
lobbied U.N.?
Clear skies
James T. Himer
=================
(4) CLIMATIC CYCLES
From Joel Gunn <jdgunn3@mindspring.com>
Benny,
I suppose that others have noticed that the return rate of the
millennial scale downturns in global temperature of unidentified
source
detected by Bond et al. (Science 14Nov97) from sea cores is
1470+/-500
years (see also Kitagawa and van der Plicht 20Feb98). If AD 536
is
counted as one of the major disruptions, we are now 1462 years
into the
cycle. Cyclicities with a millennium of standard deviation have
obvious
problems, but there is some food for thought there.
Joel Gunn
-----------------
CCNet-LETTERS is the discussion forum of the Cambridge-Conference
Network. Contributions to the on-going debate about near-Earth
objects,
the cosmic environment of our planet and how to deal with it are
welcome. To subscribe or unsubscribe from CCNet-LETTERS, please
contact
Benny J Peiser at <b.j.peiser@livjm.ac.uk>.
The fully indexed archive
of the CCNet, from February 1997 on, can be found at
http://abob.libs.uga.edu/bobk/cccmenu.html
*
CCNet SPECIAL: THE SPACEGUARD DEBATE IN THE HOUSE OF COMMONS
A RARE MOMENT OF SCIENCE & POLITICS AT THEIR BEST
----------------------------------------------------------------
Mr. Öpik: At midnight on 10 August last year, we nearly
lost the
cosmic lottery: an asteroid 1.6 km wide passed within six
hours of
the Earth. In space terms, that is very close. It equates
to the
Leader of the Opposition standing at the Dispatch Box,
throwing a
marble at the Prime Minister in a fit of pique, and
missing his
head by 2 mm. That is a sobering thought.
Mr. Adrian Sanders (Torbay): He would have lost his
marbles.
Mr. Öpik: I think it unnecessary to point out that,
unfortunately,
the Leader of the Opposition has already lost his marbles.
-----------------------
It's 10.36 pm on Wednesday, 3 March 1999. Whilst most people in
the
United Kingdom are about to go to bed, the House of Commons is
set for
an exciting, enlightened and, at times, hilarious debate about
the
impact hazard and our precarious place in space. It's a rare
moment of
science and politics at their best. If only we could witness more
often
such well researched and good humoured debates in the Mother of
Parliaments - and perhaps a wee-bit earlier.....
I have attached yesterday's entire Spaceguard debate for all list
members to enjoy. Let us hope that Mr Öpik's initiative will
actually
result in the proposed Spaceguard project at the Armagh
Observatory.
Benny J Peiser
------------------
From HANSARD (House of Commons Daily Debates)
http://www.parliament.the-stationery-office.co.uk/pa/cm199899/cmhansrd/cm990303/debtext/90303-53.htm#90303-53_head1
Spaceguard Project
Motion made, and Question proposed, That this House do now
adjourn.--[Mr. Jamieson.]
10.36 pm
Mr. Lembit Öpik (Montgomeryshire): I have a big problem with
asteroids--
The Minister for Energy and Industry (Mr. John Battle): What?
Mr. Öpik: Asteroids. And so has the rest of the human race.
Unless we
do something to stop it, sooner or later an impact with an
asteroid or
a comet will lead to the end of most life on Earth.
My grandfather, Ernst Julius Öpik, was a professional astronomer
in
Estonia and then at the Armagh observatory in Northern Ireland.
He
specialised in comet and meteorite impacts on other bodies. His
work
led to an asteroid being named after him by the astronomer
Eleanor
Helin. I guess that I may have to move to Öpik's asteroid out in
space
one day if I lose Montgomeryshire for the Liberal Democrats.
Last year, when NASA stated that an asteroid was coming towards
the
Earth, I mentioned to a journalist that I hoped that it was not
Öpik's
asteroid, prompting him to write an article with the headline
"MP to
Blame for the End of the World". He at least saw the serious
side of
the debate.
The impact hazard comes from so-called Earth-crossers. They
intersect
the Earth's orbit. If we wait long enough, one will certainly hit
us.
Earth-crossers are leftovers from the early days of the solar
system.
Think of the solar system as a cosmic building site. When God
made the
planets, he had a lot of bits left over. When he had finished, he
did
not sweep them up. They range in size from dust particles to
objects
hundreds of miles across. They float about in space between the
planets,
sometimes crashing into them.
Small crashes happen all the time. Rocks that burn up in the
atmosphere
without hitting the ground are called meteors or shooting stars.
Every
shooting star is a tiny bit of space dirt, just a few millimetres
or
centimetres across, which ends its life in a bright streak as it
evaporates in the Earth's atmosphere. For a dust particle, I
guess that
that is a pretty cool way to go.
Bigger crashes are not as common. Objects that reach ground level
are
called meteorites. They range in size from a few kilogrammes to
much
bigger objects. On 9 October 1992, a 12 kg meteorite fell in
Peekskill,
New York, punching a hole in the rear end of a car parked in a
driveway
and coming to rest in a shallow depression beneath it. It went
all the
way through the car and on to the road. I would love to have seen
the
driver's insurance claim.. Apparently, she sold the car to a
museum for
a handsome profit.
Even bigger crashes are less common, but far more explosive. On
the
evening of 30 June 1908, a small comet-like object exploded in
the
atmosphere above the Tunguska river valley in Siberia. It had the
explosive power of 10 million tonnes of TNT. It flattened trees
for 20
km in all directions and killed hundreds of reindeer. If the
Tunguska
object had entered the atmosphere over Westminster, everything
within
the M25 would have been destroyed.
We can expect two or three such objects to collide with the Earth
every
century, but it gets really scary when the objects are 500 m in
diameter or bigger. An object 1 km wide hitting land would
destroy an
area the size of Germany, raise enough dust to affect the
climate,
destroy the ozone layer and freeze crops owing to the darkness of
what
we often call a nuclear winter. For various reasons, an ocean
impact
would be even worse: it would create tidal waves called tsunamis
on a
hemispheric scale, and would kill a large proportion of more
complex
life forms--including us.
The explosive effect of an object 1 km wide is about 100,000
million
tonnes of TNT. Anything larger than that--wider than 1 or 2
km--is
called a global killer. That means that the impact of a 10 km
object
would wipe out seven of every 10 life forms on Earth. Devastation
on
such a level is almost beyond comprehension, but we know that it
has
happened before, and it will definitely happen again.
How big is the risk? There is plenty of evidence on our doorstep
that
this is not millennium madness. Every year, about 50,000 tonnes
of
space rock hit the Earth. In the half-hour of this debate, more
than
2.5 tonnes will descend on us from space. The big ones are
hanging out
there, of course, but most of that is made up of specks of dust
and
small meteorites.
In 1930, three meteorites landed in Brazil, causing shock waves
which
could be felt in La Paz, Bolivia. At midnight on 10 August last
year,
we nearly lost the cosmic lottery: an asteroid 1.6 km wide passed
within six hours of the Earth. In space terms, that is very
close. It
equates to the Leader of the Opposition standing at the Dispatch
Box,
throwing a marble at the Prime Minister in a fit of pique, and
missing
his head by 2 mm. That is a sobering thought.
Mr. Adrian Sanders (Torbay): He would have lost his marbles.
Mr. Öpik: I think it unnecessary to point out that,
unfortunately, the
Leader of the Opposition has already lost his marbles.
Had that giant rock hit the Earth, we would not be here to
discuss it.
A dust cloud would have enveloped the globe for months, and would
have
stopped photosynthesis. Plants would have died. The shutdown of
world
agriculture would have certainly put the talks on the common
agricultural policy in the shade!
The blast would have been followed by a wave--a tsunami--that
would
have risen to 4 km in shallow coastal waters. The summit of Ben
Nevis
would have been more than a mile below water. Much of human
achievement
would have been lost, and survivors would have been left
scavenging for
life, every day a dark, cold fight for existence.
The most recent big impact occurred next door. Five years ago, a
few
visitors dropped in on a neighbour of ours, Jupiter. Fragmented
comet
Shoemaker-Levy 9 crashed into Jupiter in 20 pieces in one week in
July
1994. The impacts produced Earth-sized scars in the Jovian
atmosphere.
That was an example of what we call "streams"--when a
series of objects
impact one after the other, in quick succession. With an
expectation of
one such impact every 1,000 to 2,000 years, the Jovians might
have
taken a relaxed view of the chance of being hit more than once.
In
fact, they were hit 20 times in one week. That was bad luck for
the
Jovians, but a good lesson for us. Of course, no one actually
lives on
Jupiter, but a lot of people live on Earth.
Mr. Tam Dalyell (Linlithgow): By courtesy of the British
Geological
Survey, I had the good fortune to have dinner, after a lecture
that he
had given, with the late Eugene Shoemaker, who died tragically in
Australia. His considered opinion was that the position merited
some
action, because it was as dangerous as the hon. Gentleman makes
out.
Mr. Öpik: I know that the hon. Gentleman is very interested in
the
subject. He is right to draw attention to the extraordinary
contribution made by Eugene Shoemaker, who, in the last 10 years,
created an atmosphere in which the whole question of asteroid and
comet
impacts could be taken seriously.
Here on Earth, the biggest evidence of global killers comes from
65
million years ago. This is a subject that Eugene Shoemaker often
discussed. An asteroid 10 km wide fell on Chicxulub in the
Yucatan
peninsula, in Mexico. It extinguished about 70 per cent. of life
on
Earth, and wiped out the dinosaurs. On average, such events are
expected to occur every 30 million years or so, but, as with
buses, you wait for ages and then 20 come along at once--as the
Jovians
found out.
There is other evidence. The moon is cratered simply because of
such
impacts. Interestingly, the moon itself was probably caused by
the
impact of a Mars-sized object hitting the Earth, with the moon
splashing out from our planet about 4,500 million years ago. Our
solar
system is not peaceful--we are living in a cosmic shooting
gallery,
where planets and other bodies are still colliding.
When will the next global killer strike the Earth? The next major
impact could be 100,000 years away, or it could be two minutes
away.
Unfortunately, we do not know where all these things are, so we
will be
caught by surprise if one of the unexpected, untracked and
undetected
objects comes our way. We could have as little as 20 seconds
warning
before being incinerated in the catastrophic aftermath of the
impact
and explosion. That is not enough time even to say the Lord's
prayer.
Mr. Sanders: Someone will page us.
Mr. Öpik: My hon. Friend is being optimistic if he thinks that
he will
be paged by our Chief Whip in such an eventuality.
Even though the impact represents the greatest environmental
danger
there is--far greater than an all-out nuclear war--until
recently, the
subject has been regarded as a joke. When I originally asked
about the
threats, we contacted the Ministry of Defence, which said that it
was
really a matter for the Department of the Environment, Transport
and
the Regions. The DETR passed us on to the Home Office, which
suggested
the Department of Trade and Industry.
In desperation, we asked the Library for advice. Having listened
to our
asteroid story and heard of the level of devastation that a
reasonably
large object could cause, there was silence, before the librarian
asked
whether we had thought about contacting the Archbishop of
Canterbury.
Impacts are part of science, not religion.
They are a part of cosmic life, as well as ours. The new element
is
that we homo sapiens are the first species on Earth not only
to
appreciate the dangers, but to be in a position to do something
about
them. We have the technology to avert this brand of Armageddon.
Mr. Sanders: Is my hon. Friend familiar with the recent film
"Armageddon"? Does he see the solution as being to send
Bruce Willis up
to the asteroid to drill a big hole and to let off a nuclear
weapon
which disperses the asteroid? Is that fantasy land, or the kind
of
preventive measure that we will have to take?
Mr. Öpik: Following their earlier performance, I suggest that we
consider asking for volunteers from the official Opposition for
that
role. However, if the Minister gives an unsatisfactory response,
we
might ask him to volunteer. The serious point that my hon. Friend
makes
is right. Although the science, in places, is a bit shaky in
"Armageddon", the concept is spot-on.
The impacts are part of science, but they are also part of
economics.
It is surprising that one is twice as likely to be killed by an
asteroid impact as in a plane crash, and it is six times more
likely
that that would happen than dying by tornado. As for beef on the
bone,
the chances of dying from food poisoning, including BSE, are one
in 3
million--100 times less likely than being killed by an asteroid
impact.
Unfortunately, we cannot ban asteroids. If we could, it would
make a
far bigger practical difference to public health than the current
ban
on beef on the bone. That is food for thought for all of us.
With the odds as they are, by doing nothing about asteroids and
comets,
we are all taking part in a great cosmic game of roulette. These
flying
roulette balls have a completely different effect, depending on
size.
As I have said, the smallest objects are shooting stars, which
cause
little damage. However, with the 1 km-wide objects, we must do
two
things--track and divert. We must track them, so we know what is
coming
towards us, and divert them to avert Armageddon.
We have the technology to track the objects, but we are tracking
only
about 10 per cent. of them. We cannot save the world if we see
these
objects too late. Ideally, we want a few years' notice of a
potential
impact. We could then nudge them into a modified orbit using
rockets or
nuclear explosions, as in the films "Armageddon" and
"Deep Impact", or
we could use a more exotic solution involving solar sails. The
nudge
need only be small because, in cosmic terms, Earth is a small
target--it is easier to miss us than to hit us. A little tap to
divert
the orbit soon enough will mean that life goes on as the rock
flies by.
There are about 2,000 near-Earth asteroids and possibly a similar
number of extinct comets not yet found and not bright enough to
be
discovered with existing instruments. Objects less than about 10
km
across can be diverted in principle, as long as we have years, or
perhaps decades, in which to plan. Larger objects, and even the 1
km
long-period comets, are harder to deal with because we have less
warning, but they constitute only a small part of the threat, or
actuarial risk.
The blockbusters show the way. As the films show, there are a few
enlightened people beyond Hollywood who are trying to deal with
the
problem in a serious fashion. The Spaceguard Foundation is an
international organisation which aims to track all large Earth-
threatening objects--all the global killers--and its work could
be
crucial to our future.
According to NASA, the estimated cost of setting up six
telescopes and
a global network comes to about £36 million, with roughly £6.25
million
a year running costs. That would be spread among various
countries,
with none paying more than £5 million towards set-up, and
perhaps about
£500,000 a year running costs. The United Kingdom has important
expertise and people who can make a real contribution to the
international effort.
Governments internationally should establish formal recognition
of
Spaceguard and the United Kingdom should establish a national
centre to
contribute to the international effort. Armagh observatory is a
world-
renowned centre of excellence, considered one of the best centres
of
minor planet astronomy anywhere. It is the right place for our
Spaceguard centre to be located, and perhaps the Minister will
consider
visiting it.
To set up the centre and the feasibility study group would cost
about
£4.56 million over 10 years; that is less than £500,000 a year,
and
would provide an important first step to the larger project. For
comparison, that is less than 2 per cent. of the cost of the
millennium
dome. McDonald's has given £12 million sponsorship to the dome,
which
is more than the entire cost of UK participation in Spaceguard
over 10
years. That is an amazing statistic.
Impacts of objects of about 1 km across represent a greater cost
than
£100 million in human life alone. Any insurance company must
take
seriously the opportunity to detect a danger for £1 million a
year to
save possibly £99 million a year. It is only because it is
unusual to
think about the space threat that action has not already been
taken.
Diverting the objects that are heading towards us is more
expensive,
but I have to believe that if we find something coming towards us
the
human race will be sufficiently focused to work together to
divert what
would literally be a global catastrophe.
In the past, asteroid impacts have had something of a giggle
factor.
Those talking about them have been seen as cranks. At last, we
have a
Minister who takes the issue seriously. He has been well advised
by his
experts to do so. Some hon. Members may have been laughing about
it,
but one does not see many dinosaurs laughing about it these days.
One is more likely to die in an asteroid impact than to win the
national lottery, unless one does the lottery for 100,000 years,
in
which case one will probably both win the lottery and die in an
asteroid impact, although I suspect that only Glenn Hoddle is in
a
position to find out.
I ask the Minister not to commit the Government to massive
expenditure,
but simply to arrange meetings between his Department and experts
such
as Professor Mark Bailey, who follows my grandfather in being
director
of Armagh observatory, Major Tate from Spaceguard UK and many
other international partners in the field.
I am sure that such meetings will underline the importance of
serious
UK involvement. This is not idle scaremongering. I do not set
myself up
as Parliament's Nostradamus any more than I set up the Minister
as the
Government's Bruce Willis, set to save the world from global
catastrophe; although one never sees the Minister and Bruce
Willis in
the same room at the same time.
The last time a huge asteroid hit the Earth, it wiped out the
dinosaurs. We are next in line for extinction. I am sure that new
Labour does not want to be responsible for wiping out humanity
and
allowing the cockroaches to inherit the Earth. We have come too
far to
let it all end in a searing moment of heat and light and the long
dark
winter which would follow.
For once in our history as a species, let us think long term and
make a
plan to ensure that civilisation can continue to flourish and
that life
in all its wonderful diverse forms can still inhabit an
extraordinary
place called Earth.
10.55 pm
The Minister for Energy and Industry (Mr. John Battle): I begin
by
congratulating the hon. Member for Montgomeryshire (Mr. Öpik) on
raising this subject. I thought his speech was an excellent
example of
a clear and interesting explanation of some good science. It is
not
easy to explain physics and astronomy, but the hon. Gentleman
showed
tonight that they are not beyond popular comprehension. He
presented
the subject with some seriousness, spiced with wit, and made a
marvellous speech to get science debated in the Chamber and,
perhaps,
outside it, more urgently than it has been in the past.
I am more than willing to give the hon. Gentleman the commitments
that
he sought tonight. First, I will take the subject seriously,
because we
should, and secondly, I will follow up the matter with my
colleague
Lord Sainsbury who, as Minister for Science, is responsible for
space
matters at the Department of Trade and Industry. I should be
happy to
have meetings with the hon. Gentleman, the people at Armagh and
officials to take the debate further. I would also be more than
happy
to find the time to visit the Armagh observatory, which is funded
by
the Government through the Particle Physics and Astronomy
Research
Council--PPARC. I take every opportunity to visit Northern
Ireland for
family reasons and I should like to visit the observatory and see
some
of the work that it does.
In recent weeks, we have discussed biotechnology and we now have
the
ability to observe activity at the cellular level, deep inside.
We have
also developed our capacity to reach far out into the universe
and we
should not ignore what we find. Indeed, we should try to deepen
our
understanding. Many of us who enjoy the sight of a shower of
shooting
stars on a clear spring night and the brilliance of a comet
against a
summer's day. Indeed, astronomy brings many youngsters into
science.
However, within the beauty of the universe there lurk unseen
dangers.
The dangers that we see, we should take seriously.
As the hon. Gentleman pointed out, dangers exist and threats come
from
things that are prosaically known as near-Earth objects. Part of
my job
as a Minister is to steer a course between the panic of the
immediate
moment and deep complacency. Somewhere between those two
parameters, we
should take the matter seriously. I wish to make it clear that
the
chances of the Earth being hit by any large near-Earth object
during
our lifetime is remote, but that is not an excuse and such events
have
happened in the past. Over geological time, it is probable, if
not
statistically certain, that similar events will occur again.
The hon. Gentleman outlined the two principal types of near-Earth
objects, comets and asteroids, which are some of the ancient
remains of
the earliest years of the formation of our solar system, more
than 4
billion years ago. Asteroids pass very close to the Earth's orbit
around the sun and there is evidence that some have hit the Earth
in
the past. Most of them, the smaller space debris called meteors,
are
too small to survive the rapid passage through the atmosphere and
burn
up with the trail of light that we know as shooting stars.
However,
larger asteroids have occasionally crashed to Earth, creating
craters
and the hon. Gentleman mentioned some of them. It is clear that
the
Earth, with other planets and moons in the solar system, has been
pelted, over geological time, by asteroids ever since its
formation.
Scientists estimate that there are currently some 2,000
near-Earth
objects of more than half a mile in diameter. On average, an
object of
those dimensions may be expected to hit the Earth only once in
100,000
years. Others have expressed that risk as being one chance in
25,000
that the average individual would be killed in an asteroid
collision.
That is not much higher than the risk of being killed in an
aircraft
collision, as the hon. Gentleman suggested. The reason for that
is that
although near-Earth objects impact rarely, they could have a
large
effect on our globe, its environment and people. The frequency of
impacts is far lower than that of aircraft accidents.
I am grateful to NASA for some of the information that I have
managed
to glean. NASA states:
"Such global catastrophes are qualitatively different from
other, more
common, hazards that we face daily, given that these common
events
occur much more frequently but affect fewer people. No individual
person should worry about being struck by a comet or asteroid.
The
daily threat to an average person from disease, car accidents,
home
accidents and from other natural disasters is much higher."
We recognise that, as NASA puts it,
"the Earth orbits the Sun in a sort of cosmic shooting
gallery . . . it
is only recently that we have come to appreciate that impacts by
NEOs
pose a significant hazard to life and property".
It is necessary, therefore, to ask what we should do, as my hon.
Friend
the Member for Linlithgow (Mr. Dalyell) suggested.
NASA states:
"It is entirely feasible that we could divert a large
asteroid or comet
from its orbit using existing technologies. The potential
response
depends on the lead time. If we can predict the event long in
advance,
by at least 10 to 100 years, then conventional rockets and
explosives
would probably be adequate, even for bodies as large as a
half-mile."
In a sense, the suggestions in the film referred to by the
hon.
Gentleman are not as way-out and wild-eyed as people might
suggest.
I cannot respond in great detail to the hon. Gentleman's remarks
on the
Spaceguard project, but I understand that it involves certain
groups
monitoring asteroids. The Spaceguard Foundation was set up in
1996 by
astronomers in a working group of the International Astronomical
Union
to promote and co-ordinate activities for the discovery, pursuit
and
orbital calculation of NEOs at an international level, to promote
studies of their physical and mineralogical characteristics, and
to
promote a ground network, for discovery observations, and for
astrometric and physical follow-up.
Spaceguard UK complements the Spaceguard Foundation but with a
national
emphasis. The Government's British National Space Centre held a
meeting with interested parties, including Spaceguard UK, and has
since
been in contact--close contact, I hope--with Spaceguard. The
Government
are sympathetic to the aims of the project, and Government-funded
work
is contributing to all the aims, both nationally and through
international co-operation.
The UK Schmidt telescope based at the Anglo- Australian
observatory at
Silent Springs mountain in Australia has been taking large-format
glass-plate photographs of the night sky for 25 to 30 years. The
photographs are stored in the Schmidt plate archive at the royal
observatory at Edinburgh and are an ideal database for follow-up
work
on detected asteroids that can improve orbit calculations. There
is a
continuing programme to digitise the photographs and to make the
data
easily available on the internet to astronomers worldwide.
To understand better the trajectory and possible threat of
asteroids,
research is needed into asteroids themselves. The key matters to
be
understood are the materials, their shape and their structure.
Data may
be obtained by looking at the distribution and variation of
infra-red
spectra.
The UK infra-red telescope on Hawaii has been extensively used to
study
asteroids. Additional studies will continue with the new 8 m
Gemini
telescopes. The UK is contributing to that £110 million project,
and
twin instruments are located in Hawaii and Chile. They are at the
cutting edge of technology, and they will allow British
astronomers to
be at the forefront of most areas of ground-based astronomy,
including
asteroid studies.
We are also funding our share of the mission and instruments for
the
European Space Agency's important Rosetta mission, the
third
cornerstone mission in the Horizon 2000 programme. Those
instruments
will study the detailed composition of the comet Wirtanen by
landing on
it and taking samples.
The European Space Agency is mounting a study to produce a system
for
the co-ordination of worldwide capacity in NEO research, and it
plans
to run a pilot project to demonstrate the operation of a system
to
co-ordinate observations and communicate results.
The British National Space Centre is participating in work aimed
at
keeping near-Earth space as free as possible of man-made space
debris
and at tracking debris once it is identified. That information
provides
input to collision calculations that enables orbit changes to
protect
systems such as ERS-1 and ERS-2. Key groups involved include
those at
Queen's university, Belfast, and Queen Mary's college, London.
The British National Space Centre is working with fellow members
of the
interagency debris co-ordination group to agree a procedure for
the
re-entry of risk objects. The group includes NASA, the European
Space
Agency and the Russian Space Agency, and it is collaborating on
measurements of the debris environment and improvements in the
prediction of re-entry events.
To consolidate the work of the International Astronomical Union,
the
European Space Agency, NASA and many others, an international
workshop
on monitoring programmes for asteroids and comets is planned this
June
in Italy. It is proposed that after that event, there will be a
second
United Nations meeting on the subject to build on the work and
take it
forward seriously at the highest international level.
I am grateful, as I hope are other hon. Members, to the hon.
Gentleman
for raising this subject. I hope that the debate will be more
widely
read than by those who have been able to attend. The hon.
Gentleman
presented a piece of science rather brilliantly. I strongly agree
that
the issue has to be approached with the best international
collaboration. I note carefully his proposal for a centre based
at
Armagh. My colleagues and I stand ready to discuss the matter
further
with him. Our understanding of this subject is developing. The
Government welcome such positive input. I hope that the hon.
Gentleman
is reassured that the matter can be treated seriously. He dealt
with
the topic with the wit and flair that communicates the problem
beyond a
narrow band of interest. He has done something for the popular
communication of science, for which I thank him.
Question put and agreed to.
Adjourned accordingly at six minutes past Eleven o'clock.
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