Now that our traffic seems to be flowing again, I guess I can post my regular Monday blog. Apparently there are BOINC database issues that are clogging the system, so I hope that problem's been flushed out. I predict that by the end of this week, I will have only one SETHI datacube left to finish. At the moment I have 137 done, leaving only 7 to go. Five of those are on lando, one on vader, and one on thumper. The one on thumper is the one I expect to be incomplete by week's end, because it's having this problem I get sometimes where it can't find the beamfile associated with a spectrum, so I have to restore the file manually. I also caught up to Matt again in making beamfiles for new spectra. The HI database is up to 15,697,801 spectra.

At our group meeting today we talked mostly about getting multibeam SETI@home going. It's getting really close, as Eric's successfully made a client that works on Windows, and he's trying to get one compiled on Mac OS. So, any day now I'm sure. AstroPulse is coming along too.

So now that hockey's done for the season, except the awards show as my wife likes to remind me, I have no excuses for not getting tonnes of work done. I had a nice little trip up north last week, and in about 6 weeks we'll be taking a family road trip across the continent in a somewhat triangular route, with Florida and Manitoba being the other vertices besides California.

Friday I'm going to see Sleepytime Gorilla Museum and Cheer Accident in SF. Matt lent me a bunch of music by Cheer Accident so I'll hopefully recognize some of the songs they play.

Now that our traffic seems to be flowing again, I guess I can post my regular Monday blog. Apparently there are BOINC database issues that are clogging the system, so I hope that problem's been flushed out. I predict that by the end of this week, I will have only one SETHI datacube left to finish. At the moment I have 137 done, leaving only 7 to go. Five of those are on lando, one on vader, and one on thumper. The one on thumper is the one I expect to be incomplete by week's end, because it's having this problem I get sometimes where it can't find the beamfile associated with a spectrum, so I have to restore the file manually. I also caught up to Matt again in making beamfiles for new spectra. The HI database is up to 15,697,801 spectra.

At our group meeting today we talked mostly about getting multibeam SETI@home going. It's getting really close, as Eric's successfully made a client that works on Windows, and he's trying to get one compiled on Mac OS. So, any day now I'm sure. AstroPulse is coming along too.

So now that hockey's done for the season, except the awards show as my wife likes to remind me, I have no excuses for not getting tonnes of work done. I had a nice little trip up north last week, and in about 6 weeks we'll be taking a family road trip across the continent in a somewhat triangular route, with Florida and Manitoba being the other vertices besides California.

Friday I'm going to see Sleepytime Gorilla Museum and Cheer Accident in SF. Matt lent me a bunch of music by Cheer Accident so I'll hopefully recognize some of the songs they play.

Congratulations Kevin . . . Nice goin' Sir! and that goes for the Rest of you @ Berkeley too . . .Thank You for a job well done . . .

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BOINC Wiki . . .

Science Status Page . . .

I predict that by the end of this week, I will have only one SETHI datacube left to finish. At the moment I have 137 done, leaving only 7 to go.

Congratulations Kevin . . . Nice goin' Sir! and that goes for the Rest of you @ Berkeley too . . .Thank You for a job well done . . .

Alas, my prediction is turning out to be wrong already. I'm happy to say that 3 more cubes finished in the last day, but since Jeff & Matt had to reboot lando today, I had to restart a couple of them. At least they were nice enough to wait for one of them to finish, since it was about 99% done when I got the news. So I have 140 done, and I expect one more to finish this week, and hopefully the last 3 will be done next week. So here's what 97.222222% of the Arecibo sky looks like, as seen by the flat feed:

WOW Kevin, that looks awesome!!! Thanks for sharing that. Very interesting!

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...So here's what 97.222222% of the Arecibo sky looks like, as seen by the flat feed:

Jun12SETHI.gif

Looking good and interesting.

When does that hit the publications list?... ;-)

And what's the stats for having got that lot together?

(So who says s@h isn't Science!)

Regards,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

---

Paul
(S@H1 8888)
And proud of it!

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

I don't see how we will be able to do a whole lot with Parkes. The whole dish has an area of only 0.32 hectare. The area of the whole dish of Arecibo is about 7.3 hectares; we might use as much as four hectares with the Alfa receiver, but I don't remember exactly. We can't use the whole dish at Arecibo; otherwise we would be limited to seeing only the zenith.

---

Now that our traffic seems to be flowing again, I guess I can post my regular Monday blog. Apparently there are BOINC database issues that are clogging the system, so I hope that problem's been flushed out. I predict that by the end of this week, I will have only one SETHI datacube left to finish. At the moment I have 137 done, leaving only 7 to go. Five of those are on lando, one on vader, and one on thumper. The one on thumper is the one I expect to be incomplete by week's end, because it's having this problem I get sometimes where it can't find the beamfile associated with a spectrum, so I have to restore the file manually. I also caught up to Matt again in making beamfiles for new spectra. The HI database is up to 15,697,801 spectra.

Kevin

Hi Kevin

I'd like to get your thoughts and opinions on the following:

International Lunar Observatory/Association

Introduction

The International Lunar Observatory (ILO) is a multi-national, multi-wavelength astrophysical observatory, power station and communications center that is planned to be operational near the South Pole of the lunar surface as early as 2009.

The International Lunar Observatory Association (ILOA) is the organization that supports the ILO and its follow-on missions through timely, efficient and responsible utilization of human, material and financial resources of spacefaring nations, enterprises and individuals.

History

The ILO mission was conceived during the historic International Lunar Conference 2003 (5 th meeting of the International Lunar Exploration Working Group (ILEWG)). A distinguished panel of lunar scientists, entrepreneurs, policy makers, advocates and others gathered to discuss the next vital step in human exploration of the Moon within the decade. What manifested was the Hawaii Moon Declaration, a one-page “Ad Astra per Luna” manifesto, written and signed by conference participants. Soon after the positive momentum, the ILO mission began to take shape.

An ILO Advisory Committee was established in 2005, consisting of about 50 supporters from the international science, commerce and space agency communities. The Committee convened for the ILO Workshop in November 2005 on Hawaii Island to discuss the organizational, scientific/technical and financial/legal direction of the ILO.

International, Commercial and Individual Support

Pivotal to the success of the ILO is the cooperation and support of the world’s major spacefaring powers, most notably the USA, Canada, China, India, Italy, Japan, and Russia. Fundamental to ILO advancement are the private and commercial enterprises–which catalyze, organize and help attract the support of nations. The impetus behind a unified international mission is to engage the human and material resources of these nations, enterprises and individuals into a pioneering and peaceful mission that benefits all of humanity

Current Progress with Nations

Hawai‘i

The formation of the ILOA in 2006 has initiated multiple outreaches, strategies and communications with supporters of the ILO. Relationships with Mauna Kea Support Services, Canada France Hawaii Telescope (CFHT), West Hawaii Astronomy Club, the Onizuka Space Center and the Hawaii Island Space Exploration Society, have been established.

Canada

The ILO was presented to Canada Astronomical Society (CASCA) in Calgary in June 2006, as well as the Canada Aeronautics Space Institute and the International Institute for Space Law conference at McGill University in Montreal in June 2006. The ILOA has neighborly (CB: we share the same front lawn) relations with CFHT, allies in the Canada Space Agency as well as Optech and MDA.

China

For several years, the ILOA has shared strong rapport and mutual support with chief China lunar scientist Ouyang Ziyuan, who explicitly has advocated a telescope on China’s first lunar lander Chang’e-2 mission. An ILO astronomy MOU was established with National Astronomical Observatories R&D Planning and Funding Director Suijian Xue in April. Additional rapport and ILO interest exist with Shanghai Astronomical Observatories, Chinese Academy of Sciences, China National Space Administration and the Chinese Society of Astronautics.

India

The ILO has direct support within the Indian Space Research Organization (ISRO) and the Indian Institute of Astrophysics, most notably with ISRO PRL Council Chairman and cosmologist UR Rao, lunar scientist Narendra Bhandari, current ISRO Chair Madhavan Nair.

Italy

Italy was the site of the 2005 Moonbase Symposium, which received widespread Italy industry and academia support. Italy is also the site of the 2007 ILEWG conference. The Italian Space Agency (ASI) has established agreements with China and Germany on lunar rover mission planning.

Japan

Support for ILO efforts exist within the Japan Aerospace Exploration Association, notably with lunar scientists Kohtaro Matsumoto, Susumu Sasaki, Yoshisada Takizawa and Hitoshi Mizutani.

Russia

The ILOA has rapport with prominent Russia lunar scientists Vladislav Shevchenko, Viacheslav Ivashkin and Erik Galimov.



Financing

A study performed by ILO prime contractor SpaceDev states that the first ILO mission can be launched, landed and operated within a modest budget of under $50 million USD. The strategy to fund this mission includes securing $10 million in investments (possibly at $2 million a year for five years) from various supportive government entities. These entities include science and space agencies/institutions, of Hawaii (USA), Canada, China, India, Europe, Japan, and Russia. Commercial sponsorship from high-tech companies such as Google, Cisco, Yahoo and others is also sought, as well as endowments from philanthropic groups and individuals.

Presumed Facts

“Malapert” Mountain: Located about 122 kilometers from the Lunar South Pole, the adjacent mare plain just north of the 5-kilometer high “Malapert” Mountain is the intended landing region for the ILO. Near-constant sunlight (thought to be 89% full, 4% partial) provides an energy-rich environment, and the lunar peak enjoys continuous line-of-sight to Earth and direct Earth-Moon communications. The mountain dominates its surrounding area for an excellent vantage point and is near enough to expected water ice deposits -- which can be utilized for oxygen, drinking water and rocket fuel -- around the Lunar South Pole (Shackleton Crater, Aitken Basin). Given these factors, Malapert Mountain is considered to be the most suitable location for the ILO to conduct astronomy and catalyze commercial lunar development and human lunar base build-out.

In 2003, the Lunar Enterprise Corporation (LEC) hired SpaceDev of Poway, CA to serve as the prime contractor for the ILO. A Phase A feasibility study conducted by SpaceDev concluded that “it is possible to design and carry out a private commercial lunar landing mission within the next several years. The Phase B study, conducted the following year, recommended researching a safe and accurate lunar landing navigation system that can deliver the ILO to a ‘ Peak of Eternal Light .’ Also concluded was the possibility of landing the ILO to a specific target within an accuracy of about 100 meters using “currently available commercial technology.” The ILO will utilize a mix of leading-edge propulsion, inertial navigation, and celestial navigation together with established Earth based deep space tracking to achieve the required accuracy.

Richards Master Plan

An International Lunar Observatory/Association (ILO/A) Master Plan was completed in February of 2006 by Optech Space Division Director and ISU co-founder Bob Richards. The plan outlines how to build the ILO/A as a science, organizational and commercial entity that operates within the scope of investor markets, equity players, management, industry, and customers. Key players include Space Age Publishing Company, Lunar Enterprise Corporation, Space-X (of Europe), the Canadian Space Agency, the University of Hawaii and countries such as China, India, and Russia. International MOUs would be established between the ILOA and the key players, exchanging science data and commercial communications for principal funding.

The ILO will serve as a multi-wavelength astrophysical observatory that will utilize VLF, millimeter, submillimeter, and optical wavelengths. Scientific objectives of the ILO include imaging the galactic center; analyzing interstellar molecules to determine the origin of the solar system; searching for NEOs and Earth-like planets; Earth observations; planetary and solar observations; and searching for extra-terrestrial intelligence.

The ILO has the potential for interferometrical buildout, much like the Harvard-Smithsonian Submillimeter Array on Mauna Kea that operates the first such observatory (eight mobile antennas at six meters each operating interferometrically). Another example of cutting-edge interferometry is the 64-dish Atacama Large Millimeter Array being constructed at 5,000 meter altitude in Chile’s ultra-dry high desert. Submillimeter and millimeter astronomy is forefront cutting edge science and interferometry, operating in the .25 to 1.7mm wavelengths, and offers a multitude of beneficial applications.

ILO Features and Benefits

The ILO/A strives to pioneer and innovate several niches of human, science and technological endeavor. For the benefit of science, commerce and humanity, the ILO will serve as a(n):

a. Astrophysics facility: unique and pioneering for the next frontier of astronomy, with special emphasis on advancing Hawaii 21 st century astronomical leadership.

b. Power station: a solar device will be required to supply power to the ILO and its instruments, and may offer additional capacities for other energy-related functions.

c. Communications Center: transmission of astrophysical data; Space Age Publishing Company’s (SPC) Lunar Enterprise Daily flagship publication; commercial communications, broadcasting, advertising, and imaging. A series of lunar commercial communications workshops are being conducted in Silicon Valley through the support of the SPC California office.

d. Lunar Property Rights: automatically raise the question of “who owns the Moon?”

e. Site Characterizer: gather and report data of the surrounding area, including solar wind and radiation measurements, temperature, altitude, and seismic and meteoric activity.

f. Toe-hold for lunar base buildout: serve as a pre-cursor to future missions.

g. Virtual nexus dynamic website: develop a website that delivers real-time astrophysical data, lunar video, earthrise imagery, broadcast communications and other viable information to institutions, popular media, schools and the general public

International Lunar Observatory/Association

http://www.iloa.org


Best Wishes from:
Byron
Vancouver
Canada

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

We discuss this in our science meetings from time to time. From a scientific standpoint, it would be great to get this going since we would be able to look at so much more of the sky. The severe drop in sensitivity is the one major drawback - Parkes has around 7% as much useful collecting area as Arecibo, so we would have to limit our searches to stronger signals. Still worth doing, if you ask me.

I'm not sure what you mean by Parkes doing some signal checking, but all radio observatories have to do constant RFI monitoring to ensure that man-made signals aren't interfering with astronomical observations. I'm not aware of any SETI projects being done at Parkes right now. I think I recall Dan saying once that if Arecibo has to close, then we'd look into moving all our equipment to Australia. So that's the "plan" as I see it, if you like. :) With our limited resources, it seems best to stick with the biggest and most powerful telescope for now.

Hi Kevin

I'd like to get your thoughts and opinions on the following:

International Lunar Observatory/Association

Best Wishes from:
Byron
Vancouver
Canada

Terrible website, though I'll check it again soon to see if it gets updated like they say it will. Interesting idea, though I don't see much scientific thrust behind the concept. It also appears they are overstating their affiliation with established institutions in the astronomical community. Naturally I was drawn the Canadian section:

Canada

The ILO was presented to Canada Astronomical Society (CASCA) in Calgary in June 2006, as well as the Canada Aeronautics Space Institute and the International Institute for Space Law conference at McGill University in Montreal in June 2006. The ILOA has neighborly (CB: we share the same front lawn) relations with CFHT, allies in the Canada Space Agency as well as Optech and MDA.

OK, I was at CASCA '06 in Calgary, and the ILO was "presented" as poster #103 out of 106 posters at the conference. So what? Maybe that same poster was hung on a wall at McGill later that month. That doesn't necessarily add credibility to the project. And having "neighborly" [sic, for non-US people] relations and allies doesn't impress me either. By that logic, SETI@home has far more impressive neighbourly relations and allies.

That said, SpaceDev is a well-known company and they do good work. If they're involved, this thing has a chance of flying. It'll be interesting to see what comes out of their meeting in Hawai'i this November.

ok thanks Kevin

Best Wishes
Byron

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

We discuss this in our science meetings from time to time. From a scientific standpoint, it would be great to get this going since we would be able to look at so much more of the sky. The severe drop in sensitivity is the one major drawback - Parkes has around 7% as much useful collecting area as Arecibo, so we would have to limit our searches to stronger signals. Still worth doing, if you ask me.

I'm not sure what you mean by Parkes doing some signal checking, but all radio observatories have to do constant RFI monitoring to ensure that man-made signals aren't interfering with astronomical observations. I'm not aware of any SETI projects being done at Parkes right now. I think I recall Dan saying once that if Arecibo has to close, then we'd look into moving all our equipment to Australia. So that's the "plan" as I see it, if you like. :) With our limited resources, it seems best to stick with the biggest and most powerful telescope for now.

. . . in that case - Contact Dr. Zain Upton - of BOINC SYNERGY TeAm - i am sure 'what can be done, will, or shall - work itself out and 'he' is an Exceptionally Gifted and Very Informed Individual . . .

---

BOINC Wiki . . .

Science Status Page . . .

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

We discuss this in our science meetings from time to time. From a scientific standpoint, it would be great to get this going since we would be able to look at so much more of the sky. The severe drop in sensitivity is the one major drawback - Parkes has around 7% as much useful collecting area as Arecibo, so we would have to limit our searches to stronger signals. Still worth doing, if you ask me.

I'm not sure what you mean by Parkes doing some signal checking, but all radio observatories have to do constant RFI monitoring to ensure that man-made signals aren't interfering with astronomical observations. I'm not aware of any SETI projects being done at Parkes right now. I think I recall Dan saying once that if Arecibo has to close, then we'd look into moving all our equipment to Australia. So that's the "plan" as I see it, if you like. :) With our limited resources, it seems best to stick with the biggest and most powerful telescope for now.

. . . in that case - Contact Dr. Zain Upton - of BOINC SYNERGY TeAm - i am sure 'what can be done, will, or shall - work itself out and 'he' is an Exceptionally Gifted and Very Informed Individual . . .

Having been to Pakes/Forbes in New South Wales myself as a lay tourist. The responses to my queuries about the relationship between Parkes and SETI were taken as "cool". While not talking politics it did strike me as a matter of pride,that the Americans have an approach to space sciences yet so do the Australians. Co-operation exists yes.Answers to sensitive questions are................

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I don't see how anybody could put any sizable instrument on the Moon yet - either optical or radio. It would be too heavy to transport and land. Besides, even though gravity there is less than on Earth it's still there and would cause sag. I don't know whether temperature differences on the Moon are greater than in space or not. Maybe they could put an X-ray scope in the Moon - but there already is one in orbit - Chandra. I don't know how much that one weighs. If they put another Chandra on the Moon it might just be a duplication of effort.

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For siting astronomy instruments, the moon is an expensive technical nightmare for many reasons.

Far more effective is to put instruments into orbit or at the Lagrange points.

Meanwhile, the moon is fertile ground for adventure lobbying!

There may be something to be gained with an ISS styled 'collaboration'... At the expense of the rest of scientific progress.

Keep searchin',
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

For siting astronomy instruments, the moon is an expensive technical nightmare for many reasons.

Far more effective is to put instruments into orbit or at the Lagrange points.

Meanwhile, the moon is fertile ground for adventure lobbying!

There may be something to be gained with an ISS styled 'collaboration'... At the expense of the rest of scientific progress.

Keep searchin',
Martin

Thanks, Martin. I tend to agree with what you and Clyde have said. Just to add some fuel to the fire, here are the first two sentences for the abstract to the poster for the ILO in my CASCA booklet:

A collaboration of aerospace companies from around the world, including Canada, are (sic, should be is) developing a proposal to put a small, low-cost payload on a peak near the south pole of the Moon. The scientific goals of such a mission are not yet fully defined, and this may represent an opportunity to collect astronomical data from a unique vantage point.

So there you have it. The engineers want to do it; the science is an afterthought.

Hi Kevin,

I drop by every now and then to read what has been happening and always wonder what ever happened to the plans to extend SETI@Home to the southern hemisphere, specifically, utilising data from the Parkes Telescope in Australia. I understand they have a multibeam receiver and do some signal checking on site, but what about the deeper analysis that can be done via this project? Is Parkes sensitive enough to utilise the data from it? I know during the classic days there was a plan to utilise the data, whatever happened?

Best regards,

We discuss this in our science meetings from time to time. From a scientific standpoint, it would be great to get this going since we would be able to look at so much more of the sky. The severe drop in sensitivity is the one major drawback - Parkes has around 7% as much useful collecting area as Arecibo, so we would have to limit our searches to stronger signals. Still worth doing, if you ask me.

I'm not sure what you mean by Parkes doing some signal checking, but all radio observatories have to do constant RFI monitoring to ensure that man-made signals aren't interfering with astronomical observations. I'm not aware of any SETI projects being done at Parkes right now. I think I recall Dan saying once that if Arecibo has to close, then we'd look into moving all our equipment to Australia. So that's the "plan" as I see it, if you like. :) With our limited resources, it seems best to stick with the biggest and most powerful telescope for now.

I would like to ask a question: can the SETI technology be integrated to "piggyback" off of an array telescope? It seems that "big dish" radio telescopes are not being built any longer (and, if rumors are true, will be abandoned; i.e., Areceibo). The argument seems to go that a phased array of smaller dishes is much more effective.

Australia already has one such array in operation at Narrabri, which is called the Australia Telescope Compact Array (ATCA), and Australia is in the running as one of two nations that might be awarded the site for the Square Kilometre Array (SKA).

Now, the manual for the ATCA indicates that it can be tuned to explore around the hydrogen line (1420.40575 MHz). But I don't get the impression that this can be done at the same time as other array tuning is taking place. Is it as simple as just taking a feed off of all of the available preamplified signals? Or does the adjustments required for phasing the antennas necessarily exclude parallel explorations of different frequencies?

If it is the latter, then SETI had best be collecting money for its own array!

... can the SETI technology be integrated to "piggyback" off of an array telescope? It seems that "big dish" radio telescopes are not being built any longer (and, if rumors are true, will be abandoned; i.e., Areceibo). The argument seems to go that a phased array of smaller dishes is much more effective.

That all depends on what you want to do and in what way the "much more effective" is...

For gaining greater resolution and faster operation, then a phased array is a very good idea.

Also, a seti search is to be done using the ATA (not necessarily s@h).


However, for seti and a lot of other radio astronomy, my first question would be what the system noise floor is.

One BIG dish means that you can afford to make a very much better just-the-one much more sensitive and noise-free receiver. You should also be able to get better shielding from terrestrial noise.


Anyone got any figures for what noise floor can be achieved with the ATA or SKA systems as compared to Arecibo?

Keep searchin',
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Martin, from my audio engineering days, on a mixing desk you can reduce the noise floor by ganging channels together. With two channels, the signal goes up +6dB while the noise in the system increases by +3dB because some of the random noise cancels itself out.
Of course, if part of the original signal is noise then it would provide enhanced noise, but still a cleaner signal! If it was a different random noise at each antenna, then the summation would attenuate it.

Sources of local coherent noise not originating from the source being examined would have a different phase profile, and not be accentuated because the delay compensation is tuned to the area of interest. If this interference can be identified, then it can also be neutralized.

So, for a large array of many antennas, with the right signal path delays inserted, the S/N ratio should be greatly enhanced by the time the signals arrive in phase at the combinator, and I'd argue that the signal quality would be much higher than for just one antenna.

Perhaps the same channel combination method could be used by having several detectors/channels within one dish, where phase compensation should be minimal.

Just some thoughts...

I don't know whether temperature differences on the Moon are greater than in space or not.

They’re huge; contrary to its appearance from here when illuminated against the night sky, the Moon’s surface is typically about as dark as asphalt. Moreover, since daylight and darkness occur for a fortnight at a time, there’s plenty of time for it to warm up and cool down. According to NASA’s Planetary Fact Sheet for the Moon, surface temperatures range from “>100 K to <400 K”—say a factor of three.

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