The Economist - UK (2021-11-20)

84 Science & technology The Economist November 20th 2021

Andsincethesensoryexperiencesassoci­

atedwithnewfoodscanbeoverwhelming

tothem,autisticchildrenaremorelikely

thanotherstohaverestricteddiets.Sub­

tractingthiseffectleftnoremainingsig­

nal.Theteamthusfoundnoconnection

betweenautism and microbial diversity

beyondthatbroughtaboutbyautisticchil­

dren’sfoodpreferences.Norwasthereany

detectable connection between autism

andparticularbacterialspeciesofthesort

suggestedbypreviousstudies.

Onthefaceofthings,thisisatodds

withthefindingsofthetreatment­by­mi­

crobiome­tweaking camp, led by Rosa

Krajmalnik­BrownofArizona State Uni­

versity. Her initial studies, admittedly

smallinnumber,suggestedfaecaltrans­

plants—usedinextremecasestotreatin­

fectionwithanintestinalbugcalledClos­

tridiumdifficile—hadapositive effecton

thebehaviouraltraitsofchildrenonthe

autismspectrum,aswellasontheirgas­

trointestinalsymptoms.Sheisnowsuper­

visingclinicaltrialstotestthesefindings

morerobustly.

Whetherthereisreallya contradiction

remainstobeseen.DrKrajmalnik­Brown,

while acknowledging the quality of Dr

Gratten’sanalysis,stillthinksit cannotex­

plainawaytheresultsshesawinthepre­

liminarytrials.Butitisalsopossiblethat

faecaltransplantation,byrelievingtheun­

comfortablesymptomsbroughtaboutdi­

rectly by unbalanced microbiomes, im­

provesthebehaviourofchildrenwithau­

tism,yetdoessowithoutaffectingtheneu­

ralunderpinningsofthecondition.n

ASATsandtheISS

Fragmentation grenade

“S

orryfortheearlycall”,thetransmis­

sion from ground control to the Inter­

national Space Station (iss) in the morning

of  November  15th  began,  “but  we  were  re­

cently informed of a satellite break­up and

need  to  have  you  guys  start  reviewing  the

safe­haven  procedure.”  That  meant  the

crew  of  the  iss—a  joint  venture  between

America,  Canada,  the  European  Space

Agency,  Japan  and  Russia—had  to  seal  off

some  of  the  modules  in  which  they  live

and work and retreat to the two space cap­

sules currently moored at its airlocks, lest

debris  from  the  break­up  puncture  their

living space. 

The  source  of  the  debris  was  a  Soviet­

era  spy  satellite,  Kosmos­1408,  in  an  orbit

100km or so above, and at an angle to, that

of the iss. A few hours earlier this had been

blown  to  smithereens  in  a  Russian  anti­

satellite­missile  test  which  turned  the

two­tonne  hulk  into  some  1,500  pieces  of

debris large enough for American radars to

track (meaning a few centimetres or great­

er  across),  and  countless  more  smaller

fragments. The exact extent of the cloud of

debris could not be known, but it looked as

if the isswas passing through it, and would

do so repeatedly.

America  condemned  the  test  as  “reck­

less”, stressing that it endangered not just

the five astronauts on the iss(four Ameri­

cans and a German) but also the two Rus­

sian  cosmonauts,  one  of  whom,  Colonel

Anton  Shkaplerov,  is  currently  the  sta­

tion’s commander. Russia’s defence minis­

ter,  Sergei  Shoygu,  was  quoted  in  tass,  a

Russiannewsagency,assayingthat “a cut­

ting­edge system of the future” had “hit an

old  satellite  with  precision  worthy  of  a

goldsmith.  The  remaining  debris  pose  no

threats to space activity.”

That  was  not  true.  When  a  satellite  is

destroyed  in  this  way  the  debris  starts  off

close  to  the  satellite’s  previous  position

and orbit. That was the situation when the

isswas put on alert hours after the test. Ov­

er days, the debris spreads out along the or­

bit,  forming  a  ring  around  Earth.  Over

weeks, lateral spread turns that ring into a

shell.  This  diffuses  the  risk.  But  if  Ameri­

ca’s  assessment  of  1,500  fragments  holds,

the test will have increased the total num­

ber  of  trackable  bits  of  space  debris  by  al­

most 10%. And all space debris poses some

threat to space activity.

The  fallout—or  rather,  the  fall­cease­

lessly­around—from  the  Russian  test  is

not quite as bad as that from a similar Chi­

nese  test  carried  out  in  2007,  which  ac­

counts  for  3,500  bits  of  trackable  debris.

But it is worse than the debris from an Indi­

an test which took place in 2019. That used

a target in a very low orbit, and as a result

most  of  shrapnel  has  since  re­entered

Earth’s  atmosphere.  The  same  is  true  of

America’s  own  most  recent  satellite­

smashing  escapade,  in  2008,  which  de­

stroyed a re­entering satellite said to have a

dangerous amount of fuel on board. 

Why  do  countries  keep  doing  these

things?  One  reason  is  the  link  to  missile

defence.  An  ability  to  destroy  a  satellite

with a missile launched from below, as the

Russians  did,  is  also  an  ability  to  destroy

an  intercontinental  ballistic  missile  dur­

ing the part of its flight which puts it above

the atmosphere. America prizes that abili­

ty,  and  others  seek  it.  But  testing  missile­

defence  systems,  or  for  that  matter  anti­

satellite weapons, does not require the cre­

ation of copious orbital debris with no pri­

or warning. (The Outer Space Treaty of 1967

requires  countries  to  consult  with  each

other  before  doing  anything  which  might

lead to “potentially harmful interference”.)

Such flamboyant recklessness seems to be

more  about  proving  a  point.  It  is  possible

that the timing of Russia’s test, coinciding

with  its  build­up  of  troops  on  the  Ukrai­

nian border, was intended as a signal. 

Brian  Weeden  of  the  Secure  World

Foundation,  an  organisation  devoted  to

the sustainable and peaceful use of space,

says the test “calls into question [Russia’s]

commitment to dealing with the threats to

the  long­term  sustainability  of  space  and

their  expressed  desire  to  prevent  an  arms

race in outer space.” One way in which that

desire  is  purportedly  expressed  is  in  the

“Treaty on Prevention of the Placement of

Weapons in Outer Space and of the Threat

or  Use  of  Force  against  Outer  Space  Ob­

jects”,  which  Russia  and  China  started  to

promote at the unin 2008. America and its

allies are not keen—in part, America says,

because it does not place limits on ground­

based anti­satellite systems. 

Earlier this month, though, the unGen­

eral  Assembly  voted  in  committee  for  an

“open­ended  working  group”  on  possible

norms, rules and principles for the respon­

sible  and  peaceful  use  of  space.  Despite

Russia  and  China  voting  against,  because

they  prefer  their  treaty,  open­endedness

may provide enough scope for some sort of

agreement.  But notsoon.  unprocesses,

like space debris,can stay up in the air for a

very long time.n

A Russian anti-satellite test also tests the international order in space

Just how many escape pods do we have?!