Over the past couple of weeks, I've had a poll over to the right asking how much you, as a taxpaying individual, would be willing to shell out on a yearly basis to support astronomy research. The median answer was $100. If I want to be fancy and take a logarithmic average (since I gave you options on a logarithmic scale, and counting the two "none" answers as "$1," because zeros and logarithms don't get along), I get $52.75. So, what do you actually pay?
That's hard to determine exactly, so the numbers I'm going to throw out probably overestimate the true amount by quite a bit, maybe even a factor of 2 or more. The numbers I quote come from this study by the American Association for the Advancement of Science, one of the largest and most prestigious scientific organizations in the US.
In 2007, the IRS processed 139 million individual tax returns. Now, the US government gets taxes from many other sources, like various corporate taxes, but let's assume that it all comes from individual returns. And let's assume that each of those 139 million people pays the same share. Bad assumptions, I know, but this is just an order of magnitude calculation anyway.
Most ground-based astronomy is supported by the National Science Foundation. Their fiscal year 2008 budget for astronomy was $233 million. So, that cost you $1.67 this year.
The largest chunk of astronomy money, though, comes from NASA's Science Mission Directorate, or SMD. NASA's SMD oversees (almost) all U.S. government funded space science, including the Hubble Space Telescope and other space telescopes, missions to other planets, and even satellites that study Earth's environment. It does not include manned spaceflight. For FY 2008, the NASA SMD budget was $5.2 billion. Now, we could potentially remove the Earth Science portion of that budget (about $1.5 billion), but the repair mission to Hubble (paid mainly out of NASA's Human Exploration budget), roughly balances that out. So, let's leave the number as is. So, the typical taxpayer share of NASA's astronomy research budget is $37.41.
Astronomy also gets money from elsewhere. Since the discovery of "dark energy", we've gotten some money from the Department of Energy's High Energy Physics research budget. For 2008, that budget was $689 million. About 2/3 of that goes to particle accelerator work, which we don't count as astronomy. But let's say that astronomers get all of the rest (which isn't true), or $230 million. In that case, your 2008 tax bill for the DOE astronomy research was $1.65.
Finally, the Smithsonian Institution gets $183 million a year for general research. Astronomy is just one portion of the Smithsonian's research budget, paying for a research institute in Boston and for portions of several telescopes. Let's assume that we astronomers get the whole budget, though we only get a fraction. In that case, your tax bill for Smithsonian astronomy comes to a whopping $1.32.
So, adding this all together, astronomy in the U.S. received about $5.85 billion in taxpayer money in 2008. If this is spread equally among all taxpayers, this comes to $42.05 per taxpayer per year, with most of that coming from NASA's space budget. And this is close to the logarithmic average of my very small and non-scientific poll. So, it looks like we astronomers have roughly the amount you are willing to pay us.
Just as a reminder, the 2008 budget deficit was $438 billion. So, if we eliminate all astronomy from the federal budget, the deficit would only be $432 billion. Not really a huge savings. In other words, Hubble is not bankrupting our government, which is good to know.