The Decadal Survey of Astronomy and Astrophysics set three goals for the decade : searching

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1 The Decadal Survey of Astronomy and Astrophysics set three goals for the decade : searching for the first stars, galaxies, and black holes; seeking nearby habitable planets; and advancing understanding of the fundamental physics of the universe. 1 With these goals in mind, it also suggests a research program for the next decade to set the astronomy and astrophysics community firmly on the path to answering some of the most profound questions about the cosmos. 2 However, due to the 30% cut in discretionary spending, it is necessary to trim these projects down to those that are most essential for future scientific progress. The three projects discussed in this report: the Thirty Meter Telescope (TMT), Laser Interferometer Space Antenna (LISA), and Wide Field Infrared Survey Telescope (WFIRST), are all valuable scientific projects that ranked highly in the decadal study; however, the TMT stands out as the least important project for a variety of scientific, economic, and political reasons. Thus it is the recommendation of the Office of Management and Budget that federal funding be withheld from the Thirty Meter Telescope project. Criteria In analyzing the potential of each proposed project, a number of scientific and political metrics were used to determine their relative merit. First, consideration was given to the scientific promise of each project, consisting of its potential impact on current scientific theories as well as its ability to address the goals of the U.S. scientific program. Additional scientific factors that were considered included the uniqueness of the project, i.e. whether there were currently operating or planned projects that could accomplish some of the project s goals, and the possible synergies with proposed or operating projects. Secondary consideration was given to the political aspects of each project, including the reliance on international cooperation, public relations issues, and the effects on public-private cooperation. Also considered was the effect of the project on the United States international competitiveness in the given research field. Finally, as all of the projects were estimated at similar costs and technical risk, these typically important metrics were ignored. 3 The combination of these factors, along with input from both the public and the scientific community enabled the OMB to determine which project should not be funded. 1 National Research Council, Committee for a Decadal Survey of Astronomy and Astrophysics. (2010). New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: National Academies Press. ES-1. (hereinafter Decadal Study ). 2 Id. 3 Peter Meyers. Private Correspondence (January 5, 2011).

2 Wide Field Infrared Space Telescope ( WFIRST ) The Wide Field Infrared Space Telescope is a 1.5 meter wide-field-of-view near-infrared-imaging and low-resolution-spectroscopy telescope, which will investigate the fundamental nature of dark energy. 4 Dark energy is ubiquitous throughout the universe, accounting for about 70% of its mass-energy, and yet is only know to interact via gravity. 5 Since we cannot see or feel it, it has been impossible to detect directly, and its existence has only been inferred from our cosmological models and its gravitational effects. WFIRST proposes to take wide field infrared images, and using weak gravitational lensing, supernovas, and baryon oscillations, measure the expansion of the universe, with the hope of more accurately measuring the cosmological constant which drives this expansion. Gravitational lensing is the bending of light around an object, with the degree of bending determined primarily by the mass of the object. Using this property, WFIRST will image billions of galaxies to determine their distance and rate of expansion. In addition, WFIRST will use type 1A supernova, which occur somewhat regularly in every galaxy and with the same brightness, to determine the distance to the imaged galaxies. WFIRST will also measure the baryon acoustic oscillations produced when the universe was only 370,000 years old to further constrain the cosmological constant. 6 The combination of these measurements promises to greatly advance our understanding of dark energy, which has been one of the most pressing questions in astrophysics since its discovery. The WFIRST proposal also contains a plan to search for planets in the center of our galaxy. By imaging the galactic bulge of the Milky Way, the telescope will capture instances in which a planet's orbit around a star in the center of the galaxy causes the manner in which light is bent around the system to change slightly. This effect is called gravitational microlensing, and the information gathered from imaging the effect can be used to calculate the mass of the planet and the distance at which it orbits its star. This part of the mission will allow for a survey of the number of planets in the densest region of our galaxy, and make a large contribution to the burgeoning field of exoplanet studies, which currently lacks the ability to perform such a large scale survey. Each of the experiments carried out by WFIRST will, if successful, make great strides towards the goals outlined by the decadal study. As a result, the WFIRST project meets the highest scientific expectations of an 4 Decadal Study, at Report of the Dark Energy Task Force. June 6, < Id. at 37, and Decadal Study, at 2-10.

3 applicant for government funding. Politically, there are no obvious drawbacks to this project. It can be expected to be popular with both voters in favor of looking for alien life and scientists, as it was the top recommendation from the decadal study. In polls conducted on public opinion of the goals of this project, the exoplanet search tested very well, whereas the dark energy search was deemed less interesting. 7 Having considered all of the factors presented above, the OMB concurs with the decadal study in ranking the WFIRST project highest among proposed projects for the next decade. Laser Interferometer Space Antenna ( LISA ) The Laser Interferometer Space Antenna (LISA) consists of three spacecraft which will orbit the sun five million kilometers apart in an equilateral triangular formation, and are designed to detect gravitational waves. 8 Gravitational waves are deformations in the curvature of space-time which propagate outwards from sources which can range from a planet orbiting a star to a supernova explosion. 9 LISA aims to detect gravitational waves emanating from the merging of massive black holes, binary stars in our own galaxy, and the early Universe. It operates by measuring the change in the distances between the spacecraft over time, and then using this information to measure gravitational waves with a period of 10 seconds to 10 hours. 10 Essentially, as a gravitational wave passes between the spacecraft, the distance between them will change periodically. Through detailed analysis, and using reference signals in our own galaxy, it should be possible to isolate the various signals that are contributing to the measured change in distance. 11 These measurements will shed new light on a broad range of unanswered science questions, from the formation of galaxies, to general relativity and the characteristics of the early Universe 12. LISA will address two of the three focal points designated by the decadal study. The detection of gravitational waves from the orbit and merging of compact objects with massive black holes will shed light on the process of galaxy formation in an entirely new manner. Currently, observations can only be made in the 7 Internal Polling, Office of Management and Budget. 8 The LISA Mission. NASA. < 9 Chakrabarty, Indrajit. Gravitational Waves: an Introduction. < 10 Meyers, supra note This has been shown in test studies run with plausible input data. See, e.g., Mock LISA Data Challenge. < 12 LISA and the new Science of Gravitational Waves. NASA. <

4 electromagnetic spectrum, e.g. visible light, radio waves, infrared light; however, LISA will allow the exploration of an entirely new type of signal, which promises to offer new insights into each object surveyed. In addition, gravitational waves are able to penetrate the dense plasma that was present for the first 400,000 years after the Big Bang, allowing astronomers to look back farther than has ever before been possible, a prospect which promises to reveal new information about the nascent universe, and provide data which can be used to check current cosmological theories, working towards the decadal study s goal of advancing the understanding of the fundamental physics of the Universe. 13 Finally, LISA will also map the distribution of binary star systems and other gravitational wave emitters throughout our own universe, aiding in our understanding of stellar and galactic evolution. The fidelity of LISA s goals to those outlined by the decadal survey, and its ability to fundamentally change our understanding of the universe, clearly show its scientific promise. From a political perspective, LISA offers only one concern. Since the project is a joint mission with the European Space Agency (ESA), our ability to complete the project relies on an agreement with the other parties involved. Most importantly, if ESA does not name LISA as its highest priority for the decade, the United States will have to reconsider our currently proposed plan of action, as on our current budget, funding the entire project would be unadvisable. 14 Another possible hurdle for the LISA mission is that it relies on a large amount of technology that is currently unproven in long-term space missions. Our support of this project would also be contingent on satisfactory completion of a Pathfinder mission. 15 While LISA s significant possible contributions to the advancement of science make it an attractive project, in consideration of the possible hurdles that lie ahead, the OMB has ranked it second among the projects considered. Thirty Meter Telescope ( TMT ) The Thirty Meter Telescope (TMT) is a proposed project to build a giant segmented mirror telescope (GSMT) on Maunakea, as the largest optical and near-infrared ground telescope in the world. The TMT s primary mirror will be constructed of 492 hexagonal segments, and will employ adaptive optics to reduce the interference 13 Decadal Study. 14 Decadal Study, at Decadal Study, at 7-21.

5 from the atmosphere to the diffraction limit. 16 The current proposal includes three scientific modules to be installed at construction, with additional modules to be added as funding becomes available. The first modules will be focused on spectroscopy, allowing analysis of the composition of previously unanalyzed celestial objects. In addition, its size and adaptive optics will give the TMT a higher resolution than current space-based telescopes, allowing it to take more detailed pictures of targets identified by the next generation of space telescopes. While the scientific goals of the TMT appear simpler than the other projects considered in this report, they have the potential to reveal new information about astronomical objects from planets in our galaxy to other galaxies at the edge of the visible universe. Observations from the TMT could contribute to all of the goals set out in the decadal survey, and as a result its scientific priority is very high. 17 While TMT s is very promising in scientific terms, there are a number of mitigating factors. Politically, the decision to build on Maunakea, a mountain which is sacred in the native Hawaiian religion has caused a great deal of outrage from Hawaiian citizens. 18 Currently, the directors of the TMT program are running a public relations campaign in which they promise to donate one million dollars a year to local science education. 19 This campaign seems to be working at the moment, but government support of the project could reignite tensions. In addition, the Sierra Club has been actively fighting the project in court. 20 While the political hurdles are manageable, there are a number of other reasons that the OMB suggests cutting funding for TMT. First, there are two other competing proposals for GSMTs, the U.S.-based Giant Magellan Telescope (GMT) and the European Extremely Large Telescope (E-ELT). A letter received by the NSF from the GMT board indicates that it is nearly fully financed, but would be willing to make room for a 25% U.S. Government stake. 21 The GMT is different from the TMT in a number of ways, e.g. its primary mirror is only 24.5 meters and it is composed of only seven segments, but the goals of projects are very similar. In addition, the E-ELT has a mirror diameter of 42.5m, significantly larger than both US based proposals. In combination, the existence of these two projects means that if funding is withheld from the TMT project, a U.S.-based GSMT will still be built, and likely surpassed by a larger European GSMT, and if the TMT is funded, two U.S.-based GSMTs will be built, and 16 Charles Huajie Cao. Private Correspondence. (January 5, 2011). 17 Meyers, supra Note McAvoy, A. (2010, June 28). University of Hawaii approves giant telescope. Associated Press, < 19 Final Environmental Impact Statement: Thirty Meter Telescope Project. (University of Hawai i at Hilo). Volume Moku Loa Group News Archive. The Sierra Club. < 21 Letter from Wendy L. Freedman, Chair, GMT Board, to Dr. William Smith, President, AURA, Inc. and Wayne Van Citters, Director, Division of Astronomical Sciences, National Science Foundation (March 31, 2008).

6 surpassed. The project scientist for the TMT dismisses these concerns, claiming that the TMT project is a more practical project, while the E-ELT is more ambitious. While the TMT project may be more practical, putting practicality ahead of more ambitious projects would likely cause the US to fall from being at the forefront of astronomical research. 22 The only benefit from a U.S. investment in TMT would be a 25% share in telescope time, while the downsides include pulling funding from other promising programs, political fallout, and investing in a project which is likely to quickly be surpassed. In the opinion of the OMB, these factors make TMT the ideal candidate for budget cuts. Conclusions While all of the reviewed projects have promising scientific goals, the final recommendation not to fund the TMT is the result of three factors. First, there is already a nearly fully-financed U.S. based GSMT project, GMT, under way, and government support of the TMT might impact the GMT project s ability to raise capital. This could create a government sponsored monopoly on GSMTs, and possibly crowd out private investors. Second, the E-ELT project is planning to build a GSMT that will be significantly larger within the same timeframe, making it unlikely that the U.S. will be a global leader in this field. Third, there are a number of political issues surrounding the construction of the telescope, adding political costs to funding the TMT. Weighing these potential negatives against the scientific gains, the OMB finds that the TMT is the least beneficial project, and recommends that funding be denied. 22 Cao, supra note 16.

7 Bibliography Chakrabarty, Indrajit. Gravitational Waves: an Introduction. < Charles Huajie Cao. Private Correspondence. (January 5, 2011). Final Environmental Impact Statement: Thirty Meter Telescope Project. (University of Hawai i at Hilo). Volume 1. Letter from Wendy L. Freedman, Chair, GMT Board, to Dr. William Smith, President, AURA, Inc. and Wayne Van Citters, Director, Division of Astronomical Sciences, National Science Foundation (March 31, 2008). LISA and the new Science of Gravitational Waves. NASA. < McAvoy, A. (2010, June 28). University of Hawaii approves giant telescope. Associated Press, < Mock LISA Data Challenge. < Moku Loa Group News Archive. The Sierra Club. < National Research Council, Committee for a Decadal Survey of Astronomy and Astrophysics. (2010). New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: National Academies Press. Peter Meyers. Private Correspondence (January 5, 2011). Report of the Dark Energy Task Force. June 6, < The LISA Mission. NASA. <