ESA is currently carrying out studies with industry concerning the feasibility of merging the satellites, and is keenly interested in foreign involvement to save mission costs. The timing is right for Canada to enter as a full partner into this program by providing necessary hardware for one or both satellites. There is great scope for Canadian industry to benefit, and enormous potential for public interest in the scientific results.
Whether merged or separate,
the combination of FIRST and Planck is a program with extraordinary capabilities,
far beyond any other experiments being contemplated at similar wavelengths.
Planck promises to map the entire Cosmic Microwave Background (CMB) at
all scientifically interesting frequencies and angular scales, and will
thereby provide an answer to the most fundamental questions about the origin
and final fate of the Universe. FIRST will provide a breakthrough in high
spatial and spectral evolution imaging in the far-infrared and sub-millimetre
range, which will result in the discovery of the first galaxies to form
after the Big Bang, as well as a wealth of information on the formation
and evolution of galaxies, the structure of our own Galaxy, and the nature
of comets.
Background
The recent report by the Space Studies Board of the U.S. National Academy of Sciences? rated the number one priority in all of astronomy to be the "determination of the geometry and content of the Universe by measurement of the fine-scale anisotropy of the cosmic microwave background". The number two priority is the "investigation of galaxies near the time of their formation at very high redshift".
There is an exciting opportunity for Canada to become involved in both of these endeavours through joining the FIRST/Planck program.
The FIRST/Planck program is a successor to NASA's Cosmic Background Explorer (COBE, launched in 1989), and is likely to provide much more definitive and exciting conclusions. Results from COBE touched off a media storm, reaching the front page of virtually every major newspaper around the globe. Intense worldwide television coverage followed. The results captured the imagination of scientists as well as the public; Stephen Hawking remarked "it's the greatest discovery of the century - if not of all time''. We expect that the FIRST/Planck program will further excite the public's desire to understand our origins.
The Planck Surveyor is a dedicated Cosmic Microwave Background experiment designed to image the temperature fluctuations over the whole sky, with unprecedented sensitivity and angular resolution, using both bolometer and HEMT technologies. It has been selected as 'M3', the third Medium class mission of the European Space Agency's (ESA) Horizon 2000 Scientific Program, due for launch early in the next decade.
FIRST, the Far-Infrared and Sub-millimetre Telescope, is a Cornerstone (CS4) ESA mission that will perform photometry and spectroscopy in the 85- 600 m m range. It will have a 3.5-m telescope and a payload of three instruments housed inside a superfluid helium cryostat. These instruments will allow studies of our own Galaxy as well as the most distant galaxies with incredible sensitivity at wavelengths that are unobservable from the ground.
ESA now considers these two satellites to be part of the same scientific program. Both are planned to launch into an orbit near the Earth-Sun L2 point. The joint cost has been set at 630 MAU (around Can. $900M). Studies are currently being conducted to investigate the possibility of merging the two satellites onto a single spacecraft or single launch vehicle, or whether enough costs can be saved to fly the satellites separately (the scientifically preferred solution). The timing is therefore ideal for Canada to become involved. In considering a possible Canadian role, it is important to understand that ESA is responsible for the spacecraft, integration, launch, and mission operations, but has a limited involvement in the instruments.
There are three scientific reasons for contributing directly to the spacecraft. First, saving ESA money will allow design flexibility to permit a better realization of both satellites than would otherwise be possible. Second, contributing to mission costs will give Canadian scientists full involvement in all the science resulting from Planck. Third, joining the mission for FIRST gives access to data from the 'survey', which is expected to be extraordinarily exciting. In order to accomplish these things, Canada must contribute to ESA's mission costs at a significant level.
NASA has already committed itself to both of these efforts. Participation in FIRST is part of NASA's strategic plan for 2000- 2004, and U.S. investigators and companies will play a critical role in instrument development and some aspects of the spacecraft, at more than US $80M. Planck is part of NASA's longer-term mission set, with full participation by U.S. scientists and industry in the instrument teams, currently at the ~ US $10M level.
Science Summary
FIRST: One of the major breakthroughs that can be expected from FIRST is the discovery of large numbers of dust-enshrouded proto-galaxies. Recent observations by the Hubble Space Telescope and the best ground-based telescopes are beginning to provide the first direct information on how galaxies appeared only a few billion years after the universe began. Lessons from star-forming regions in the local universe indicate that very young galaxies are likely to contain such large amounts of gas and dust that they are difficult, if not impossible, to see at optical wavelengths. Observations of these 'proto-galaxies', which are critical for building a complete picture of galaxy formation and evolution, require sensitive, space-based observations such as will be possible with FIRST.
FIRST will also provide us with a wealth of new and detailed information on the interstellar medium in our own Galaxy and other nearby galaxies. Such studies, covering a wide range of chemical abundances and star formation activity, are an important complement to the proto-galaxy observations, which generally cannot resolve the details of the internal structure of the distant galaxies. The combination of state-of-the-art receivers and large collecting area will allow FIRST to make the first detailed studies of high-excitation spectral lines in the interstellar medium of external galaxies.
Planck: Precise measurements of the angular power spectrum of the CMB will revolutionize our understanding of the Universe as a whole. Planck will measure the spectrum of these fluctuations down to around 5 arcminutes, to an accuracy close to the fundamental limit, providing essentially all the available information about the large-scale composition of our Universe. It is expected to reveal key information about the nature and amount of dark matter, the precise initial conditions which laid down the seed fluctuations which grew to form all the objects we observe today, and to finally decide just how fast we are expanding, and whether we will continue to expand forever.
In addition Planck will detect the characteristic microwave signatures produced by hot gas in clusters of galaxies, allowing detailed investigation of how and when galaxies clustered together. It will also provide an incredible bank of data for investigating `foreground' material in our own Galaxy, through the production of all-sky images of unparalleled accuracy and sensitivity at nine frequencies from 30 to 857 GHz.
Canadian Research Excellence: In the context of current
Canadian research, FIRST is a natural follow-up to both the ODIN satellite
and the ground-based James Clerk Maxwell Telescope (JCMT). In the FIRST
spectral band, the JCMT is the premier ground-based instrument. Through
its partnership in that instrument, Canada has a leading technical and
intellectual role in studying the far-infrared sky. The ODIN satellite
(a collaboration among Sweden, Canada, France, and Finland due for launch
in 1998) involves university astronomers from across Canada, as well as
scientists from NRC. FIRST is an ambitious international program where
Canadians can play a prominent role because of our technical and scientific
expertise.
Several Canadian scientists play leading roles in studies of the Cosmic Microwave Background, which Planck will pursue. Two of them are already members of the small US team associated with Planck. The CSA sponsored sub-orbital program BAM is a leading experimental effort in this field. That group has decades of experience using bolometers in space to study the CMB.
The Canadian Institute for Theoretical Astrophysics (CITA) is probably {\it the} pre-eminent centre in the world for studying the problems that observations with FIRST/Planck will address. Results from FIRST/Planck, in particular on the questions of the origin of the universe and galaxy formation, will elicit broad interest from both the astronomical community and the public at large.
Canadian Industrial Expertise
The FIRST/Planck Program is technically challenging and its successful completion will involve many of the capabilities of the Canadian aerospace industry. There are a large number of subsystems of the spacecraft that could easily be provided by Canadian companies. There is sufficient expertise in Canada in several of the crucial areas, that our contribution could allow ESA to perform these missions better.
We stress that what follows are only examples; what is clear is that Canadian expertise is very well-matched for us to become actively involved in this Program, and that there are enormous potential benefits for Canadian industry.
First we list sources of items which our European colleagues have explicitly asked about:
This list is far from exhaustive and is given as an illustration that Canadian industry is well-matched to the needs of the FIRST/Planck Program. Which particular items Canada can best contribute will be a matter of negotiation between CSA and ESA.
Budgetary Considerations
Contribution to the Mission: In order for Canada to become fully engaged in the FIRST/Planck program, we have to contribute a significant amount to the mission costs. In practice, we believe this means spending around Can $20M on one or more subsystems for the spacecraft; the exact amount is clearly subject to negotiations between CSA and ESA. We expect this money to be spent entirely in Canada. Further spending on the instruments is highly desirable, but will not be possible without sharing some of the mission costs.
Mission funding of around $20M is likely to be the minimum acceptable contribution that allows Canada to fully participate in the mission; it is also sufficient for building a significant subsystem of the mission. With two distinct scientific programs, and the possibility of Canadian industry providing several smaller sub-systems, we are afforded many different options. Hence a detailed budget would be inappropriate at this time.
Canadian scientists and companies should have the opportunity to become involved in instrument development for both scientific programs. At a minimum, some nominal amount is required to maintain a direct involvement, and to provide sufficient momentum to be able to apply for other sources of funding (NSERC and industrial), should such funding opportunities become available.
Involvement in a major space mission such as FIRST/Planck requires additional funding for the scientific side of the mission, such as money for postdocs, graduate students, computers, travel, laboratory expenses, etc. We anticipate partnership NSERC/CSA funding to support the scientific and coordination activities associated with the several years around launch.
Contribution to the Instruments: For FIRST, we have a clear opportunity to contribute to the instrumentation on board the spacecraft if sufficient funds are available. We have been approached by SRON (Netherlands) as to whether Canadians would be interested in building the local oscillator control unit (LOCU) for the heterodyne receivers for FIRST. The LOCU provides the bias and control signals as well as the phase lock for the dual-polarization heterodyne channels covering the wavelength range 250 to 600 m m (450 to 1300 GHz). This instrument contains 5 heterodyne mixers, each of which will likely require 4 local oscillators (LOs) to cover the entire frequency range. Thus, there will likely be 20 independent LOs in the receiver. With the usual engineering, development, and flight models plus spares, it is likely that 60 units will have to be built. For 60 units, the cost is estimated to be Can $15-20M. The LOCU is something for which Canadian industrial expertise already exists, hence the motivation for the original inquiry by SRON. Indeed, two companies have already expressed strong interest in this contract, MPB Technologies in Montreal, and NexLink in Ottawa. So, under an optimistic funding scenario, we could also become engaged in FIRST instrumentation through additional funding of around $15M.
For Planck, there are opportunities for involvement in either of the two instruments (LFI and HFI). Canadian expertise in the CMB is certainly recognized and involvement by Canadians is welcomed. If significant further funding were available, say at the $5- 10M level, then there is great scope for Canadian scientists and Canadian industry to become fully engaged in instrument development. There is Canadian know-how in, for example, cryo-coolers and amplifier technology of the sort used on the LFI, and 3He refrigeration and bolometric technology of the sort used on the HFI. Our European and US colleagues have expressed openness to negotiating Canadian involvement in these systems.
Budget Summary: Our estimate of an optimal budget for
participation in FIRST/Planck is somewhere around the $45M level. At this
level Canada would play a prominent role in all aspects of this joint program,
and showcase Canadian industry in a high-profile setting.