Comment Re:Are they ever going to finish it? (Score 1) 92
Hi, I work for the Radio Astronomy Lab at UC Berkeley, which is the group that runs the Hat Creek Radio Observatory. When the observatory was founded in the 1950's, the primary consideration was radio quietness. The location is in somewhat of a natural bowl, geologically speaking, sheilding it from a lot of radio noise, but by no means all (reflections from airport radars can be seen off of Mt Lassen and Mt Shasta just to name one from many sources).
We already have the infrastructure there, so, it makes sense to build more telescopes there. The primary cost of building has nothing to do with the real estate. Leasing more land from local land owners is a small part of the cost (an extremely small one).
The physical maintenance of the antennas should not be taken lightly. With 350 of them planned for the future, at least a few, perhaps a dozen will be down for maintenance work everyday. We've already done work to streamline the process of building (one antenna a day is the goal). Plus, we simply don't have the money to do one big construction push.
For those comparing to the VLA, the cost of construction for the VLA was about $78 million dollars in ~1975 dollars (http://www.rozylowicz.com/retirement/vla/very-lar ge-array.html). Adjusting for the changes in currency valuation, that's approximately $285million in 2005 dollars (using http://www.bls.gov/cpi/home.htm to adjust). Note, that does not include the costs to research and design the system, which was many more millions.
So far, the ATA has cost less than $20million and at completion should be more capable than the VLA in many ways and cost about 90% less to build.
And, it's primary mission is to do science with SETI operations piggybacking on the surveys taking place.
You are severely underestimating the total data needs of the system. For the ATA to do the best interference mitigation that it can do, the correlator would peak at about 194GB/sec of data throughput. We won't push the correlator to do that for many reasons, but even a data rate of say 100MB/sec means that a possibly typical observation for 4 minutes would consume 24GBytes. As you might imagine, a data feed that could transport
a constant 100MB/sec away from the observatory would be prohibitively expensive.
We've been discussing making the ATA an imaging instrument, in that the raw data is thrown away after a much smaller and easier to handle "image" is generated. These sorts of design considerations will also flow into the upcoming Square Kilometer Array.
To do this imaging may require a small beowulf cluster.
So, yes, you are underestimating the size of the station wagon needed.
And finally, the RAL is a teaching institution, fully part of the astronomy department of UC Berkeley. This means we want undergrads/grads/postdocs/researchers to have access to the site and it be a teaching environment, which means that the telescopes are not just built in the middle of nowhere, to be left alone producing data in the quiet wilderness.
For more info on the array, check out the wikipedia entry:
http://en.wikipedia.org/wiki/Allen_telescope_array
P.S. Using the CPI conversion for your parents house cost of $37,000 in "the 70's" (I'll use 1975 again), the equivilent amount in 2005 dollars is: $135,068.87.
We already have the infrastructure there, so, it makes sense to build more telescopes there. The primary cost of building has nothing to do with the real estate. Leasing more land from local land owners is a small part of the cost (an extremely small one).
The physical maintenance of the antennas should not be taken lightly. With 350 of them planned for the future, at least a few, perhaps a dozen will be down for maintenance work everyday. We've already done work to streamline the process of building (one antenna a day is the goal). Plus, we simply don't have the money to do one big construction push.
For those comparing to the VLA, the cost of construction for the VLA was about $78 million dollars in ~1975 dollars (http://www.rozylowicz.com/retirement/vla/very-la
So far, the ATA has cost less than $20million and at completion should be more capable than the VLA in many ways and cost about 90% less to build.
And, it's primary mission is to do science with SETI operations piggybacking on the surveys taking place.
You are severely underestimating the total data needs of the system. For the ATA to do the best interference mitigation that it can do, the correlator would peak at about 194GB/sec of data throughput. We won't push the correlator to do that for many reasons, but even a data rate of say 100MB/sec means that a possibly typical observation for 4 minutes would consume 24GBytes. As you might imagine, a data feed that could transport
a constant 100MB/sec away from the observatory would be prohibitively expensive.
We've been discussing making the ATA an imaging instrument, in that the raw data is thrown away after a much smaller and easier to handle "image" is generated. These sorts of design considerations will also flow into the upcoming Square Kilometer Array.
To do this imaging may require a small beowulf cluster.
So, yes, you are underestimating the size of the station wagon needed.
And finally, the RAL is a teaching institution, fully part of the astronomy department of UC Berkeley. This means we want undergrads/grads/postdocs/researchers to have access to the site and it be a teaching environment, which means that the telescopes are not just built in the middle of nowhere, to be left alone producing data in the quiet wilderness.
For more info on the array, check out the wikipedia entry:
http://en.wikipedia.org/wiki/Allen_telescope_arra
P.S. Using the CPI conversion for your parents house cost of $37,000 in "the 70's" (I'll use 1975 again), the equivilent amount in 2005 dollars is: $135,068.87.
