Astronomy

8m-class telescope

LSST

8 m

8.4 m

Primary mirror

diameter Field of view

0.2°

3.5°

Full Moon

is 0.5°

34 ASTRONOMY • MAY 2018

With the immense amounts of data

LSST will produce nightly, it will be

essential for researchers to stay on top of

the imagery. For this, LSST scientists

have developed systems that automati-

cally process images by looking for differ-

ences between two exposures of the same

section of the sky that were taken at dif-

ferent times. This automation will allow

any changes to be noticed within a min-

ute. However, the road to understanding

the f lagged events will still require hours

upon hours of analysis.

“We need to develop these tools so that

they can operate on these quadrillions of

numbers,” says Ivezić. “Today we have

these tools if you want to apply them to

millions or even billions of objects. But if

you want to scale them up by a factor of a

thousand, it’s not a trivial thing. These

tools can mean the difference between

amorphous piles of ones and zeros and

potentially paradigm-shifting discoveries.”

Crowdsourcing astronomy

Astronomers have determined that as

many as 400 billion stars exist in our gal-

axy, while likely hundreds of billions of

galaxies exist in the observable universe.

And, with the help of new large-scale

surveys, these numbers could keep grow-

ing. Thanks to computers, scientists no

longer have to hand-count dots on pho-

tographic plates. But even with machines,

there is still far more data out there than

any scientific cohort, no matter how

dedicated, can tackle.

Enlisting the public’s help in scientific

endeavours dates back more than a cen-

tury to birdwatchers tracking aviary

migration patterns across North

America. But it wasn’t until the rise of the

internet and the online gaming culture

that citizen science projects really took

off. The idea is simple: Engage the public

by having them explore real images to

identify simple objects or patterns in a

fun, gamelike way. With citizen science,

the types of routine analyses that would

typically require months of work by a few

scientists can now be done by many more

science enthusiasts at their leisure.

One of the first groups to enlist the

public’s help at the data processing stage

was a team of scientists at NASA’s Ames

Research Center. Using data collected by

the Viking orbiters, which were sent to

Mars in the 1970s, the team developed

ClickWorkers, an online site where the

public could identify and map craters on

the martian surface, in 2000. The initial

results showed the public was both enthu-

siastic about helping and capable of per-

forming tasks accurately. Soon after, the

project was expanded.

“The majority of people participated

because they wanted to be a part of

research,” says Lucy Fortson, an astro-

physicist at the University of Minnesota

who has worked extensively with citizen

science projects. “They felt that they

wanted to do something meaningful with

their extra time.”

Today there are numerous citizen sci-

ence projects in astronomy, such as

CosmoQuest, Milky Way Project, and

perhaps most famously, Galaxy Zoo. In

Using the Australian Square Kilometre Array Pathfinder, Ray Norris plans to carry out the

Evolutionary Map of the Universe (EMU) survey to investigate radio sources in the sky. Although

2.5 million radio sources are already known, EMU expects to take on another 70 million more.

A comparison of the field of views for a typical 8-meter-class telescope and the uniquely designed

Large Synoptic Survey Telescope (LSST). LSST CORPORATION; ASTRONOMY: ROEN KELLY

Same size, different sight

SKA ORGANIZATION