2019-06-01_All_About_Space

1941 and 1972 that may have

been as big, if not bigger, than

Carrington, but had surprisingly

little impact. “It might be that the

biggest parts occurred over parts

of the world where there wasn't

the technological infrastructure to be

disturbed,” says Scott.

There was also a storm in July 2012

that narrowly missed the Earth and fortunately

hit a solar-observation spacecraft from the Solar

TErrestrial RElations Observatory (STEREO)

mission. It was travelling fast enough that if it had

been on target it would have triggered a modern-

day Carrington-like event. If we are not to be

so fortunate during the next solar cycle we will

need to investigate ways to provide more detailed

forecasts of what is coming at us.

“It’s like on Earth; we can say the winter will be

colder than the summer and we will get more rain,”

says O’Brien. “But what you really want to know

is if it is going to rain on the day of your party.“

However, there are challenges replicating our ability

to predict Earth weather in space.

Meteorologists utilise a vast network of monitors

collecting data 24/7 as satellites constantly track

weather systems from above in order to run their

increasingly sophisticated simulations.

And while we have models

of the solar wind and how it

propagates through space and

interacts with the Earth, we

can't look down on the entire

system as we can when tracking

tropical storms or rain fronts.

“Imagine yourself as a meteorologist

back in the pre-space age in the 1950s,

and you are trying to make sense of all these spot

measurements without the benefits of a satellite

picture. That's probably where we are with space

weather,” says Scott.

Reliable space weather forecasts will also require

a greater understanding of the relationship between

what we see on the Sun’s surface and what is in line

to hit us several hours or days later. To help in this

endeavour we have sent up a community of craft

to monitor the Sun. However, they are all primarily

scientific missions sent up to answer scientific

questions. “They are proving useful, but they are

not optimal,” says Scott, whose STEREO mission

can only provide data at the end of each day, which

isn't much use when really powerful, fast-moving

storms can get to Earth in 17 hours.

The scientific community are in regular

contact with industry and space agencies who are

working to ensure they have spares at the most

What if our

Sun became

too active?

With enough notice and

preparedness we could

negate the dangers and

simply enjoy the greatest

light show of all time

Alleyestotheskies

If major solar activity were

to threaten Earth, our solar

sciencecommunityandtheir

legion of orbiters as well as

land-based observatories

wouldneedtoworkoutthe

likelihood, scale and arrival

date of a direct hit.

Planes take the long

way around

To avoid endangering staff and

passengers with exposure to

high radiation levels, operators

of transatlantic flights would be

encouraged to avoid usual ‘over

the poles’ routes.

Astronauts take refuge

During an intense solar storm

any planned spacewalks are

cancelled and astronauts would

beaskedtosetthemselvesup

in the most shielded modules of

the station.

Satellites switched to

safe mode

Ifgivensufficientnoticeofan

incoming solar storm satellite

operators would be encouraged

to switch any orbiting units to

safe mode.

Saving power

To avoid widespread blackouts

power companies will

need significant stocks of

replacement transistors and

crew deployed on the ground

to tend to damaged parts of

their grids

The greatest light

show on Earth

Onepositiveeffectofintense

solaractivityisthechance

formorepeopletoenjoythe

northern and southern lights at

much lower latitudes than usual

are bathed in aurorae.

Solar surveyors

In order to better understand

and anticipate solar weather

spaceagencieshavesentupa

family of orbiters, satellites

and probes.

“A lot of satellite operators choose not to

worry about forecasts because they do not

have sufficient accuracy” Professor Chris Scott

Clockwise,

top left: A

CME blasting

from the

Sun's surface

in the

direction

of Earth

A massive

sunspot

around the

size of Jupiter

is identified

by the SOHO

spacecraft

in 2003

Satellite

operators

have been

warned

of the

dangers a

large solar

storm

could pose

The Sun goes

through a

natural solar

cycle every

11 years,

composed of

significant

increases and

decreases in

sunspots and

eruptions

© NASA; ESA;

Sun