Canada Partners on Upcoming Japanese X-ray Space Observatory

Launch: 2015
Status: In development

New X-ray Eyes Will Reveal the Most Cataclysmic Events in the Cosmos

Artist's illustration of ASTRO-H

Artist's illustration of ASTRO-H. (Credit: JAXA)

Imagine being able to peer into the innermost sanctums of monster-sized black holes and the remains of titanic explosions of stars. That is exactly the mission of ASTRO-H, an ambitious next-generation X-ray space telescope currently under development by the Japan Aerospace Exploration Agency (JAXA) with contributions from the United States, Europe and now Canada, through the Canadian Space Agency (CSA).

Slated for launch in 2015, ASTRO-H will include five specialized X-ray telescopes and detectors. Together, these instruments will look at cosmic sources of X-rays at unprecedented resolution. With this superb sensitivity, ASTRO-H will explore the most energetic and mysterious phenomena in the Universe, involving particles at energies that can't be readily produced in Earth-based labs.

Canadian precision technology on board

Canada is involved in one of the spacecraft's key instruments, the Hard X-ray Telescope. It will be deployed at the end of a six-metre mast that is expected to twist and bend; this is due to on-orbit vibrations and the extreme day-night transitions the spacecraft will experience as it orbits the Earth at 550 km, where temperatures swing from -30°C to +40°C.

Recognizing Canadian expertise in space optical and vision systems, JAXA approached the CSA in 2009 to explore the possibility of Canada providing an innovative measurement system for the mission's Hard X-ray Telescope. Following a mission concept design phase, Neptec Design Group of Ottawa, Ontario, was awarded a CSA contract to develop a Canadian ASTRO-H Metrology System, or CAMS. ASTRO-H Metrology System, or CAMS will be able to precisely measure the mast's distortions to a level of accuracy equivalent to the width of a human hair, allowing mission operators to calibrate the data of the Hard X-ray Telescope and significantly enhance the telescope's performance.

In return for this critical piece of hardware, Canada secures positions from Canadian institutions on the mission's Science Working Group, involving top scientists from around the world, notably from Japan, the US and Europe. Members of the group will be offered prime observing time on the space observatory soon after launch, for a period of approximately nine months. Data will then be made available to all scientists, including Canadian astronomers.

The CSA has selected three University astronomers to represent Canada on the Science Working Group and support Canada's ASTRO-H Metrology System, or CAMS Project:

  • Dr. Luigi Gallo, Principal Investigator for ASTRO-H Metrology System, or CAMS, of Saint Mary's University;
  • Dr. Brian McNamara of the University of Waterloo; and
  • Dr. Samar Safi-Harb of the University of Manitoba.

The funding support provided by the CSA will allow these scientists to pursue advanced astronomical research with the ASTRO-H mission as well as participate in the International ASTRO-H Science Working Group meetings in Japan and in other parts of the world.

Illustration of CAMS onboard ASTRO-H

Illustration of ASTRO-H Metrology System, or CAMS onboard ASTRO-H. The ASTRO-H Metrology System, or CAMS consists of two laser units (each approx. 15 cm cube) mounted on the satellite and a corner cube optical reflector installed at the end of the space observatory's 6 metre mast where the hard X-ray telescope sensors are located. Laser beams rapidly pulsate from the ASTRO-H Metrology System, or CAMS units onto the corner cube that reflect the beam back into the unit where lateral displacements are measured down to a level of accuracy equivalent to the width of a human hair (approximately 60 micrometers). By comparing the measured lateral displacement on each sensor, the rotation about the telescope's main axis can be determined and the data acquired at the time of observation can be calibrated to a much higher level of accuracy than in the absence of the Canadian measurement system. (Credit: CSA)

Leading-edge astronomy: Hunting down cosmic predators

ASTRO-H will peer down the throat of super-massive black holes that lurk at the heart of distant, young galaxies. Astronomers hope to get an unprecedented peek into the inner clockwork of the largest of these galactic predators that are billions of times more massive than our Sun.

ASTRO-H will also focus on unraveling the mysteries behind the remnants of star blasts known as supernovae. Astronomers believe that everything in the cosmos–even humans–was made from heavy elements forged in large part inside ancient supernovae. By using unmatched spectral resolution, combined with the ability to focus high-energy X-rays, ASTRO-H will make the most precise measurements ever obtained of the chemical ingredients that go into making these colossal cosmic explosions, and will probe the sites of particle acceleration to the highest energies.

According to the Canadian Principal Investigator for ASTRO-H mission, Dr. Luigi Gallo, this mission is a unique opportunity for Canada. ASTRO-H will mark the first time Canada is part of an X-ray astronomy mission that will explore the unseen Universe in unprecedented detail. Because of the CSA's contribution to ASTRO-H, "Canadian scientists get a chance to go to the front of the line in getting time to use this unique astronomical telescope," said Gallo, Professor of Astronomy at St. Mary's University, Halifax, Nova Scotia. "There is no doubt that we will be making big discoveries when it opens for business in three years time."

Dr. Gallo will be making good use of his time on board ASTRO-H to study the ebb and flow in the X-rays belched out by the supermassive blackholes. These fluctuations in the amount of X-rays are thought to be directly correlated to the amount of material being gobbled up by the black hole: any nearby stars, gas and dust clouds get swept up from the plane of the surrounding inner region of the galaxy. As matter is sucked in by the gravitational pull of the black hole, it gets torn apart and superheated, shooting radiation back out in space, which ASTRO-H will detect.

Astronomers believe early on in a galaxy's life, supermassive black holes sweep up most of the surrounding material in the galactic core. The black hole eventually quiets down as it runs out of cosmic things to eat; these voracious cosmic predators then calm down, allowing their host to become a normal galaxy (much like our own Milky Way).

ASTRO-H will be able to look at the very closest region around these giant black holes where the most intense X-ray radiations are being emitted. Not only will this give astronomers a clearer picture of how these cosmic predators evolve, but also how galaxies like our own came to be.

Dr. Samar Safi-Harb of the University of Manitoba will be investigating with ASTRO-H the high-energy phenomena associated with the supernova explosions of massive stars that form some of the most exotic compact objects in the Universe: neutron stars. These phenomena include particle acceleration of cosmic rays to extremely high energies, the formation of the heavy elements essential for life, and the physics of the extreme associated with neutron stars and their associated high-energy nebulae. Such studies will be enabled by ASTRO-H's combination of its broadband X-ray spectroscopic coverage, hard X-ray focusing capability, and the unprecedented spectral resolution offered by its X-ray micro-calorimeter.

Dr. Brian McNamara, Professor of Physics and Astronomy and University Research Chair in Astrophysics at the University of Waterloo, will use ASTRO-H to study powerful outbursts from massive black holes located at the centers of galaxy clusters. The energy released by matter falling onto supermassive black holes weighing more than one billion suns is equivalent to the mechanical energy of ten billion supernova explosions. This energy drives outflows of chemically-enriched gas hundreds of thousands of light years into space. ASTRO-H will measure the mass and speed of the outflowing gas, allowing McNamara's team to determine the rate at which supermassive black holes are growing. The measurements will also help to unravel the nature of the mysterious extragalactic "radio jets," which are streams of energetic particles flowing from the centres of galaxies at nearly the speed of light. ASTRO-H will advance our understanding of energetic feedback from supermassive black holes, an area in which Dr. McNamara is a recognized expert.