“We are all excited—and at the same time scared—
because this project is of a bigger order of magnitude
than anything we have done so far.”
What’s the best
Each day, write down
all the things you
have to do. When
you have done them,
the best feeling.
One skill every
Listen to others.
Best book you’ve
Aztec, a novel by Gary
Jennings. It’s about
somebody who never
Sailing in the
without a destination
holders. I listen to my colleagues before making a
decision, and try to make clear they can express
their opinions and that my decision will be based
on having listened to them—even if sometimes it is
completely different from their wishes.
Who are the stakeholders you’re managing?
It’s a huge community, thousands of astronomers
from the 14 ESO member states. There are the engineers. There are financial stakeholders. And then
there are the delegates from each member state. ESO
receives money from its member states, and member
states expect a return on that outlay. When issuing
contracts, we have to take into account the geographical return of money to the various member states.
Given this telescope will be the first of
its kind, how did the team test the design
before constructing it?
Computational tools can simulate the performance
of the telescope in sophisticated ways. These tools
simulate aging, gravity, thermal deformation and
optical performances. We also produced prototypes
of the critical components of the system—in particular, components that have never been used in
the past. We didn’t implement things that were not
fully tested in a climatic chamber simulating conditions on the Cerro Armazones mountain in the
Atacama Desert. These include an altitude of 3,000
meters ( 9,843 feet), strong ozone, strong radiation
and extreme dryness.
What technological challenges does this
The primary mirror will be composed of 798
hexagonal segments, each around 1. 4 meters ( 4. 6
feet) wide. All of them have to be phased to each
other as if they form one single optical surface.
So we need to place them just a few nanometers
from each other. We also need to maintain the
reflectivity surface—a challenge because dust will
be deposited on the surface of the mirror and the
reflective coating will age. From lessons learned at
Paranal Observatory, which is only 25 kilometers
( 16 miles) away, we know that we need to remove
the old reflectivity material and replace it with a
new one every 18 months to maintain the optical
quality. So every single day, we will remove two
of the 798 segments of the telescope, bring them
down to the washing and coating unit, and replace
them with fresh segments.
The project will take 10 years to complete.
What difficulties does that timeline present?
Keeping all the requirements under control. There
are requirements that affect other requirements, so if
I have a requirement on the mount of the telescope,
this affects another requirement on the primary mirror. There are thousands of them. So the question is,
How do we keep them under control? We do that
by putting all the requirements in a database and
linking them to each other. This is done by several
people who understand each system. So in the future,
if a contractor asks for a change, we can quite easily
identify what else will be affected.
To prepare the telescope site, the team
removed the top of Cerro Armazones
mountain. What did that entail?
The mountain is really in the middle of nowhere.
The closest inhabitants are more than 120 kilometers (75 miles) away. There is no road, no electricity,
no cellular coverage—nothing at all. We exploded
something like 5,000 cubic meters (177,000 cubic
feet) of rocks. I was really happy, very touched by
the fact that we were starting to prepare a platform
to look several billions of years into the past. It’s
exciting to be part of that. PM