Olivia Lim has never known a universe unpopulated by alien worlds.
Before she was born, a handful of planets had already been discovered beyond our own solar system. While she was growing up in St. Hubert, Que., that handful grew to thousands. As she was preparing to enter university, a star called TRAPPIST-1, located just 40 light-years away, was shown to host multiple Earth-sized planets. Now, as a PhD student at the University of Montreal, Ms. Lim is about to be handed the most exquisite astronomical instrument ever devised to find out if any of the planets circling TRAPPIST-1 have atmospheres.
“It’s surreal,” she said. “On a daily basis, what I do is I sit in front of my computer and I code. … It’s so down-to-earth. But at the same time, it’s very out in space.”
Out in space is where Ms. Lim and legions of other astronomers will be focusing their attention after the launch of the James Webb Space Telescope, which could take place as early as Christmas morning based on weather conditions. The US$10-billion NASA observatory is designed to peer at the edges of the known universe, as well as zoom in with unprecedented clarity on nearer targets, including TRAPPIST-1.
An imagined view of the TRAPPIST-1 system. Canadian astronomers will be among those using the James Webb Space Telescope to determine which of the system's seven planets have atmospheres.NASA/JPL-Caltech
The promise of Webb is a chance to see what no one has seen before. In Ms. Lim’s case that could mean picking up the signature of an atmosphere when one of the planets that orbits TRAPPIST-1 crosses in front of the star. “If the planet has an atmosphere, then part of the light of the star is going to get filtered through the atmosphere,” she said. If certain wavelengths of light are absorbed more than others, the result may reveal the composition of the atmosphere. “In the best-case scenario, it would be possible to detect water vapour.”
More than 25 years in the making, Webb is the first telescope large enough and precise enough to make such a measurement from space, where the infrared light that is most revealing about other worlds is not blocked by Earth’s atmosphere. And that’s just the beginning.
“Everything we receive in the first year or two will be new discoveries, in a sense, because we just didn’t have the technology to do these types of observations before,” said Els Peeters, an astronomer at the University of Western Ontario. Dr. Peeters is co-leading a team that will be among the first to test Webb’s abilities by gathering data on the dust and gas that surround massive stars in the iconic Orion Nebula – places where the raw materials for future stars and planets are made.
One of Webb's first projects will involve peering at dust and gas around massive stars in the Orion Nebula.NASA, ESA, M. ROBBERTO ( SPACE TELESCOPE SCIENCE INSTITUTE/ESA), HUBBLE SPACE TELESCOPE ORION TREASURY PROJECT TEAM
But the road to discovery has not been easy. Since it was conceived in the mid-nineties, the telescope has had to overcome technical hurdles, budget issues and years of delay. More recently, even its name has been in question because of a debate over the legacy of James Webb – the NASA administrator who led the agency during the lead-up to the Apollo moon landings but who is alleged to have participated in discrimination against gay and lesbian employees when he was a U.S. State Department official.
Indeed, so long and arduous has been the telescope’s journey to the launch pad, and so profound its potential impact, that its success will usher in not just the next step in cosmic exploration but an entire new generation of explorers. It is notable how many of them are women. This is partly the result of a blind competition that allocated time on the telescope based on the scientific merit of proposals. Many who were successful are also located in Canada, where researchers are leading or co-leading 26 projects slated for Webb’s initial round of observations. Collectively, Canadian astronomers are guaranteed 5 per cent of the telescope’s time by virtue of the fact Canada provided two of the instruments that will fly aboard Webb.
“The engagement is very high,” said Sarah Gallagher, an astronomer and science adviser with the Canadian Space Agency. “It’s not the only thing going on, but it’s a really big part of the community’s activity.”
Earth
orbit
SUN
Moon
orbit
Hubble orbit
570 km
L2
Note: Graphic is not to scale.
Webb will orbit Lagrange point 2 – a spot 1.5 million kms from Earth, where the gravitational pull from Earth and the sun balance out – allowing the observatory to remain in a stable position
Earth
orbit
SUN
Moon
orbit
Hubble orbit
570 km
L2
Note: Graphic is not to scale.
Webb will orbit Lagrange point 2 – a spot 1.5 million kms from Earth, where the gravitational pull from Earth and the sun balance out – allowing the observatory to remain in a stable position
Earth orbit
SUN
Moon orbit
Hubble orbit
570 km
L2
Note: Graphic is not to scale.
Webb will orbit Lagrange point 2 – a spot 1.5 million kms from Earth, where the gravitational pull from Earth and the sun balance out – allowing the observatory to remain in a stable position
2
1
3
4
5
6
7
8
9
Primary mirror
Almost six times bigger than Hubble’s, 18 gold-plated beryllium hexagons give much greater light-gathering capability
1
Secondary mirror
Reflects light from primary mirror into science instruments
2
Sunshield
Tennis court-sized layers block light from sun, moon and Earth to keep telescope at -223C, essential to see faint infrared light without interference
3
Integrated Science Instrument Module (ISIM)
Includes the Canadian-built fine guidance sensor (FGS) and near infrared imager and slitless spectrograph (NIRISS)
4
Spacecraft bus
Controls power and other support systems
5
Spacecraft bus Control, power and other support systems
6
Earth-pointing antenna
7
Solar power array
8
Trim flap
Helps stabilize satellite
9
SIZE COMPARISON TO THE HUBBLE TELESCOPE
James
Webb
6.5m
Hubble
2.4m
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
2
1
3
4
5
6
7
8
9
Primary mirror
Almost six times bigger than Hubble’s, 18 gold-plated beryllium hexagons give much greater light-gathering capability
1
Secondary mirror
Reflects light from primary mirror into science instruments
2
Sunshield
Tennis court-sized layers block light from sun, moon and Earth to keep telescope at -223C, essential to see faint infrared light without interference
3
Integrated Science Instrument Module (ISIM)
Includes the Canadian-built fine guidance sensor (FGS) and near infrared imager and slitless spectrograph (NIRISS)
4
Star trackers
Help to keep telescope pointed at target
5
Spacecraft bus
Controls power and other support systems
6
Earth-pointing antenna
7
Solar power array
8
Trim flap
Helps stabilize satellite
9
SIZE COMPARISON TO THE HUBBLE TELESCOPE
James
Webb
6.5m
Hubble
2.4m
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
Secondary mirror
Reflects light from primary mirror into science instruments
Primary mirror
Almost six times bigger than Hubble’s, 18 gold-plated beryllium hexagons give much greater light-gathering capability
Integrated Science Instrument Module (ISIM)
Includes the Canadian-built fine guidance sensor (FGS) and near infrared imager and slitless spectrograph (NIRISS)
Trim flap
Helps stabilize satellite
Sunshield
Tennis court-sized layers block light from sun, moon and Earth to keep telescope at -223C, essential to see faint infrared light without interference
Solar power array
SIZE COMPARISON TO THE HUBBLE TELESCOPE
Earth-pointing antenna
James
Webb
6.5m
Spacecraft bus
Controls power and other support systems
Hubble
2.4m
Star trackers
Help to keep telescope pointed at target
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
For an instrument that could plausibly offer our first hints of life on other worlds, it seems fitting that Webb is the most alien-looking telescope that has ever flown.
Unlike its celebrated predecessor, the Hubble Space Telescope, it has dropped the traditional “flying can” design, which consists of a cylinder built around a single piece of curved glass that gathers and focuses the light of distant objects. The problem with that approach is that “you’re limited by the size of the rocket that you can put your telescope into,” Dr. Gallagher said. That’s why Webb will travel folded up – like an insect inside a cocoon. Only after it takes off from its launch site in Kourou, French Guiana, will it open up its giant mirror, comprised of 18 gold-plated hexagons spanning a surface area almost as large as six Hubbles.
Equally important is the telescope’s sensitivity to infrared light. This requires Webb to operate at a temperature of -228 C so that the warmth of the mirror itself doesn’t outshine the distant universe. To achieve this, the telescope will be shaded behind a five-layer thermal barrier roughly the size of a tennis court that can deflect the sun’s heat.
1
Folded
2
Sunshield structure unfolds
3
Sunshield layers extend and separate
4
Secondary mirror deployed
5
Lateral wings of primary mirror deployed
Folded
1
Sunshield structure unfolds
2
Sunshield layers extend and separate
3
Secondary mirror deployed
4
Lateral wings of primary mirror deployed
5
1
2
3
Sunshield structure unfolds
Sunshield layers extend and separate
Folded
4
5
Secondary mirror deployed
Lateral wings of primary mirror deployed
Webb will focus on infrared range of electromagnetic spectrum, allowing it to observe objects too old and too distant for Hubble to see
Visible
X-rays
UV
Infrared
Radio waves
James
Webb
Hubble
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
Webb will focus on infrared range of electromagnetic spectrum, allowing it to observe objects too old and too distant for Hubble to see
Visible
X-rays
UV
Infrared
Radio waves
James
Webb
Hubble
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
Webb will focus on infrared range of electromagnetic spectrum, allowing it to observe objects too old and too distant for Hubble to see
X-rays
Ultraviolet
Visible
Infrared
Radio waves
James
Webb
Hubble
Infrared capabilities will allow Webb to see far enough to explore what the universe looked like around 100 to 250 million years after the Big Bang, when the first stars and galaxies began to form
Hubble
James
Webb
First galaxies
13.8
(Today)
12
9
6
3
0
(Big Bang)
Age of universe (billions of years)
THE GLOBE AND MAIL, SOURCE: GRAPHIC NEWS
What astronomers are hoping to gain from all this is not simply a better view but something new and unexpected. “It is absolutely going to be a game changer,” said Jan Cami, a professor at the University of Western Ontario who will use Webb to study large carbon molecules in interstellar space.
Canada’s role in the new space telescope was made official in 2007 when then-prime minister Stephen Harper’s government awarded a contract to the Ontario-based aerospace company COM DEV (now part of Honeywell International) to build Webb’s fine guidance sensor and a second instrument. The decision was a huge one for Canadian astronomers, particularly those who felt Canada had lost out by not taking part in the Hubble project. It was also a crucial choice for NASA, since the fine guidance sensor is what allows the telescope to stay locked onto its target.
“Every image coming out of Webb will be guided by a Canadian eye,” said René Doyon, a professor at the University of Montreal and the principal investigator for the Canadian Webb science team. “It is absolutely critical – it has to work.”
While the development of the fine guidance sensor was originally led by John Hutchings, now retired from the Herzberg Astronomy and Astrophysics Research Centre in Victoria, it was Dr. Doyon who shepherded Canada’s other contribution.
It was supposed to be a tunable filter that was part of a larger detector. But the Canadian component was dropped after a reconfiguration of the telescope, leaving Dr. Doyon to figure out what to do.
His solution involved building the instrument as a stand-alone on the flip side of the fine guidance sensor. Then, in June, 2011, he broached the idea with NASA and European members of the Webb team.
“It was a bit of a surprise when I presented it,” Dr. Doyon said. “The plan was done very much under the radar.”
The idea was well received, but it left him with one frantic year to create the near-infrared imager and slitless spectrograph (NIRISS), a device whose characteristics will make it especially valuable for exploring planets in nearby solar systems, among other targets. The instrument was delivered to NASA in 2012.
Together with the fine guidance sensor, Canada’s contribution to the project will total $117.8-million, plus $16.5-million for science support.
Canada's contribution to the James Webb Space Telescope arrives at a NASA facility in Greenbelt, Md., in 2012.Chris Gunn/NASA
A portion of that science will include exploring cosmic history by capturing light from objects so distant it was emitted when the universe was less than 5 per cent of its current age. Stretched by the expansion of space, that light has now been shifted to the infrared part of the spectrum. Webb will be the first telescope capable of perceiving it.
“We’re basically looking back as early as we can go towards the Big Bang,” said Chris Willott, an astronomer at the Herzberg centre who is the Canadian project scientist for Webb. As part of Canada’s dedicated time on the telescope, Dr. Willott and his team will use a technique known as gravitational lensing to pick up light that has been bent by the gravitational pull of giant clusters of galaxies to look at an even earlier epoch in the universe’s history.
An artist's concept of a young galaxy forming with a giant black hole at its centre. A Canadian project will use the Webb telescope to search for similar galaxies at the edge of the visible universe.NASA, ESA and J. Olmsted (STScI)
In this way, the telescope may become the ultimate conduit of the past speaking to the future. In a more human sense it has already done that, since the extended timeline of the project has meant that those who first envisioned it have passed the baton to those who will be the first to use it.
Madeline Marshall, an astronomer at the Herzberg who earned her PhD last year and is now leading a project on Webb that will look at remote galaxies harbouring giant black holes, said she has long visualized the moment when she may be the first person to see celestial objects that were previously hidden from human eyes.
“I don’t think I can explain how exciting that is,” she said, adding that all the data that Webb gathers will be made available to the scientific community within a year. “It’s not just the most experienced people that get to use it. It’s something for all of us – and that’s really great.”
An artist's impression of the telescope's launch. To avoid reflected light from Earth, the telescope is being sent to a point 1.5 million kilometres away.D. Ducros/European Space Agency