Talk:Radio astronomy

VLBI definition

I altered the definition of VLBI to point out that VLBI differs from conventional interferometry by the need to record data and ship it before it can be correlated. — Preceding unsigned comment added by 192.87.1.200 (talk) 20:03, 16 January 2003 (UTC)

UHF 37

UHF channel 37 is reserved in North America for radio astronomy. I have linked here from North American broadcast television frequencies; can someone who knows better explain what the particular significance of that frequency is? (I know it's an important spectral line of something, and that's as far as I can take it.) 18.24.0.120 04:50, 28 January 2004 (UTC)

Nikola Tesla

I have re-edited the entry about Nikola Tesla. Tesla's observation is definitely not a "Historical development" since it did not lead to any development and in fact Tesla had an erroneous theory about where the signals were coming from (Talking with Planets). Since this wasn't "Radio astronomy" or even an established "Radio astronomy" fact the inclusion of Tesla in this article may not meet Wikipedias notability requirements. It is at best a footnote so I have made it such. Halfblue 15:39, 14 January 2007 (UTC)

Earliest observation

Main article: Teslascope

In 1899, the eccentric Nikola Tesla, in accord with many other plans of his, planned to build a tower in a experimental station at Colorado topped by a copper ball that he would turn into a sensitive radio telescope. While investigating atmospheric electricity in 1900, Tesla noted repetitive signals that he deduced must be coming from a non-terrestrial source. Although Tesla mistook this to be radio communication from intelligent beings living on Venus or Mars it may have been the earliest observation of an astronomical radio source (A 1996 analysis indicated Tesla may have been observing Jovian plasma torus signals).

I have moved the (above) section on Tesla's observation to talk because it seems to be non-notable re: the topic of the article. I think the standard for including this in a basic article about Radio Asronomy would be "is this what would be found in the Radio Astronomy chapter of a standard Astronomy text book". So far based on my research, the answer no. The section heading is also incorrect - "Earliest observation" implys that Tesla did in fact make an observaion of an astronomical object, and the sources don't support that. Halfblue 17:52, 9 May 2007 (UTC)

It was the earliest observation. It was misunderstood. It has been noted in many books (his biographies, etc.) about Tesla.

It's not in alot of Radio Astronomy textbooks, but it is from reliable analysis ... Radio Asronomy textbook have ignored this, probably though ignorance ... please don't remove referenced material. J. D. Redding 03:00, 15 May 2007 (UTC)

The idea that Tesla made observations of an astronomical source (Jovian plasma torus signals) is a theory, not a fact. So you cannot say "It was the earliest observation". Adding a theory to an article that is supposed to be about the basics of Radio Astronomy violates Wikipedia's NPOV guidelines re: Undue weight. "If a viewpoint is held by an extremely small (or vastly limited) minority, it does not belong in Wikipedia (except perhaps in some ancillary article) regardless of whether it is true or not; and regardless of whether you can prove it or not." So this would be ok in a Tesla article but not in a Radio Astronomy article. Wikipedia is also not the place to publish original research. Halfblue 01:42, 19 May 2007 (UTC)

This is noted in several biographies of Nikola Tesla. The biographers are not a "minority". It is verifiable and reliable. Please do not removed the referenced material. J. D. Redding 04:47, 19 May 2007 (UTC)

Do note ... The Almanac of Science and Technology: What's New and What's Known is not a bio of Tesla and it even state this. A small paragraph on this is not giving undue wieght. This is not OR nor is it a "extremely small (or vastly limited) minority" held view (many people know this, such as the almanac writers). J. D. Redding 04:56, 19 May 2007 (UTC)

The report was so vague, that nobody could duplicate the observation, either immediately or decades later, or determine conclusively whether anything on Earth or elsewhere was actually observed. When scientific work is done so sloppily that it can only produce fruitless speculation, it may be of biographical interest but it lacks scientific importance Jim.henderson 13:11, 19 May 2007 (UTC)

Please explain how it is "fruitless speculation"?

The observation can be duplicated by building the apparatus that he used ...

Have you heard of this before? Or is it so jarring that you are putting it down?

Please don't edit to prove your point ... and please do not removed the informaiton ...

Tesla developed the technology to do this ...

It is of scientific importance ... that is why engineers have analyzed it ... J. D. Redding 13:56, 19 May 2007 (UTC)

References

Expansion material - re Tesla

Earliest observation

Main article: Teslascope

In 1899, the eccentric Nikola Tesla, in accord with many other plans of his, planned to build a tower in a experimental station at Colorado topped by a copper ball that he would turn into a sensitive radio telescope. While investigating atmospheric electricity in 1900, Tesla noted repetitive signals that he deduced must be coming from a non-terrestrial source. Although Tesla mistook this to be radio communication from intelligent beings living on Venus or Mars it may have been the earliest observation of an astronomical radio source (A 1996 analysis indicated Tesla may have been observing Jovian plasma torus signals).

Please use this to expand the article ... J. D. Redding ... — Preceding undated comment added 13:58, 19 May 2007 (UTC)

References

Furhter discussion - re Tesla

I figure this is a matter in which compromise is possible. That is, don't make out like it's a significant bit of astronomical history or claim that the Tesla report was precise enough to allow someone to replicate the observation or to determine whether anything was actually observed, but do make a link to an article about Ben Yahuda and other silliness. Jim.henderson 14:55, 20 May 2007 (UTC)

I did cut down the length.

I added other people that did work pre-1930s ...

With aid of Tesla's Colorado Springs Notes, 1899–1900, the data is precise enough to allow someone to replicate the observation ...

Put a link to Ben Yahuda's book.

There is no "sillyness", though ...

J. D. Redding 18:17, 20 May 2007 (UTC)

Tesla doesn't belong in this article because of WP:REDFLAG. If you can find a mainstream critical source for Tesla doing radio astronomy, show us. But relying on Tesla-junkies to source your claims is really not going to cut it. --ScienceApologist 11:59, 21 May 2007 (UTC)

Please stop making POV edit and removing referenced material as per usual you conduct. J. D. Redding 12:14, 21 May 2007 (UTC)

I have reverted (again) the references to Tesla (this also reverts other additions that seem not to follow Wikipedia guidelines per ScienceApologist above). The whole section seems to be a POV push and at the least needs trimming per "think of the reader".

The Tesla reference does not fit in this article in its present form for the following reasons:

• Tesla was not conducting Radio astronomy in 1899 or in fact at any other time in his career.
• It is POV to call Tesla's antenna a "radio telescope" since it may not have been directional and Tesla never had any concept that there were emissions from stellar sources (a well know primary use of a Radio telescope).
• Tesla thought that the signals he observered were "Little Green Men", not Astronomical.
• The linked article at Teslascope indicates it is a factual error to call the 1899 device a "Teslascope" since it states that a Teslascope is a "transceiver" for "the intention of communicating with extraterrestrial life on other planets". The 1899 antena was a receiver for studying atmospheric radio emissions.

All of this points to Tesla being irrelevant re: Radio Astronomy, although he may be a valid footnote in the current draft of the article if the editing problems above are addressed.

Halfblue 13:40, 21 May 2007 (UTC)

• Tesla was conducting observation of non-terrestrial sources in 1899.
• Tesla's antenna is a "radio telescope" objectively. Tesla understood directionality, Tesla helped develope radar. Tesla did think that the signals were from intelligence, primarily because of the repetitive nature of the signals. Tesla thought that the signals he observed were from intelligences on Mars [as many scientists of hte time thought that mars was inhabitated. (Please do not foist current knowledge on history)
• The linked article at Teslascope indicates the 1899 device a "Teslascope" is a "transceiver". One use is for "the intention of communicating with extraterrestrial life on other planets". The 1899 antenna was a receiver, among other uses, designed to receive non-terrestrial signals.

Various authors have cited the information in relation to radio astronomy and should be included. J. D. Redding 14:02, 21 May 2007 (UTC)

• Tesla was conducting observation of atmospheric electricity sources in 1899 and stumbled on a strange signal he thought was a non-terrestrial long range radio communication (this is not astronomy).
• Understanding directionality and building a "Radio telescope" are two different things. Telsa's 1899 equipment/antenna was for studying atmospheric electricity sources/interference and seems to be non-directional - that makes it NOT an astronomical "radio telescope" by definition.
• The wording is "The Teslascope was a radio transceiver designed by Serbian scientist Nikola Tesla with the intention of communicating with extraterrestrial life on other planets." By definition the 1899 device is not a Teslascope because Tesla would not have built a device to communicate with someone on the other end of a transmission he had not even heard yet. The James F. Corum (1996). Nikola Tesla and the electrical signals of planetary origin describes an antenna for receiving only, not the two way Teslascope. Even if we have a "Teslascope" here it is by no means a "Radio telescope" for "Radio Astronomy", it is a long range comunication device for talking with someone on the other end.

Calling any of what Tesla did "Astronomy" with a "Radio telescope" is stretching into POV beyond what the citations support. Halfblue 01:14, 22 May 2007 (UTC)

Re-arrangement, editing, and expansion of article

I have expanded, arranged, and general edited this article to make it a more basic overview of the subject (Radio Astronomy). I am replacing the image 7c gal.gif because it does not fit WP:IMAGE criteria of a "good image", re: "large enough to reveal relevant detail" even when viewd at (full) size. Halfblue 18:25, 12 June 2007 (UTC)

Cleanups

I rm'ed this diagram to talk because it makes no sense:

...i.e. it is all WP:JARGON. It either needs very good explanation or needs clearer version like the one seen at Telescope. 70.211.139.20 (talk) 20:42, 21 December 2009 (UTC)

Restored. It is a valid diagram, although I'd agree there needs to be a bit of explanatory text for go with it (So... yes it's jargonny if you have no background in the topic). Maybe some savvy editor can add a bit to help explain ... or maybe I will later ... or ... :-) Vsmith (talk) 00:37, 22 December 2009 (UTC)

...err, encyclopedia's are written for people with no background in the topic. So a diagram that can only be read by someone with (substantial?) background in the topic is not encyclopedic (I have a pretty good background in this topic and still can't make heads or tails of it). The image has big problems re:Wikipedia:Images#Image choice and placement - the supporting text is about atmospheric opacity but this is not a an atmospheric opacity diagram such as this, the caption is more about SETI, and the image is hard to read unless you make it very big. This image seems to have been simultaneously dumped into three articles[1][2][3] on the same day with out any modification as to its usage or description. It may be useful to someone who is looking for the particular information this graph may present but Wikipedia is not a textbook or scientific journal nor an image host. 75.224.213.249 (talk) 15:01, 22 December 2009 (UTC)

history

Bibcode:1969AJ.....74..131B Extragalactic Radio Sources, JG Bolton, 1969 -- this looks like something that can be used to expand the history section. 65.94.47.63 (talk) 11:58, 11 June 2011 (UTC)

Perytons origin

This may be of interest to the authors, Perytons are caused by microwave ovens near a radio telescope Article: http://phenomena.nationalgeographic.com/2015/04/10/rogue-microwave-ovens-are-the-culprits-behind-mysterious-radio-signals Study: http://arxiv.org/abs/1504.02165 http://arxiv.org/pdf/1504.02165v1.pdf Jcardazzi (talk) 11:06, 13 April 2015 (UTC)jcardazzi

This borders on vandalism. re Orchison and Slee

...from the inside, not the out. It is very, very clear that Orchison and Slee were the authors of a paper on discoveries of solar radiation in WWII, not independent discoverers in 2002. [diff] First making the outrageously impossible claim that anyone could "independently discover" something which was common knowledge for 50 years, then blaming the source for "self-puffery," rather than their own error. Anmccaff (talk) 01:25, 25 February 2016 (UTC)

Orchison listed himself and Slee as independent discoverers in doi:10.1007/1-4020-3724-4_5. He gives a citation to a 2002 publication, but they did plenty of work on radioastronomy back in the 1940s when they worked for the CSIRO Radiophysics group. Bibcode:2006JAHH....9...35O has plenty of citations covering that. However, this is self-puffery, because if you do read Bibcode:2006JAHH....9...35O, you'll see that their worked at CSIRO was "inspired by the almost simultaneous arrival of three reports", one by Reber, one by Alexander, and one by the AORG. So they cannot be discoverers, because they did follow up work. Call that vandalism if you want, the article is accurate. Headbomb {talk / contribs / physics / books} 01:56, 25 February 2016 (UTC)

Slee did not claim to be a discoverer, and where does Orchison's article even claim he was involved?

The article is not accurate, at least on this narrow part, it is slanted to reflect a POV, and the course of your edits make that very, very, obvious. Anmccaff (talk) 16:17, 25 February 2016 (UTC)

I didn't say Slee claimed that (maybe he did), but Orchison certainly did. See doi:10.1007/1-4020-3724-4_5. And which part of the current version isn't accurate? Headbomb {talk / contribs / physics / books} 17:02, 25 February 2016 (UTC)

...i.e. "see a dead link?" Again?

Let's run through this from the top. You decides, based on a tempest-in-a-teapot at The Signpost, that somebodies name had to be added. You added them with an inaccurate claim implying that Alexander had been the discoverer. Then you amended this...i.e., conceded it was inaccurate, but claimed she was the first to publish...which is also, of course, inaccurate.

I then added accurate sourceable information that showed, conclusively, that Alexander was not the first to publish, Reber was. You reverted it, and restored your POV version. The reason you cited was lack of references...which you yourself did not add, oddly. I restored an accurate version, and pointed out the lack of references for your inaccurate claim. You restored your inaccurate claim, and added a source which did not support, and could not support, your contention. Then you added a blitz of sources, one of which explicitly disagreed with your contention. I restored an accurate version, and provided a source which explicitly and accessible listed Reber as first published. You then added a laundry list of names, including one person who wrote about the subject, but made absolutely no claim to the discovery. You then changed the article, blaming the source for your mistake. (I think this is easy enough to follow just running through the history, but if anyone needs diffs, lemme know.)

That's bad editing, incompetent or POV driven editing at best, dishonest at worst. Cut it out. Anmccaff (talk) 17:24, 25 February 2016 (UTC)

Now that you've fixed your error, without indication, of course, of the change here, the reader can see that this is an extract-only of a source | already listed in full in pdf form...and that nowhere in it does Orchiston make this claim. Anmccaff (talk) 20:15, 25 February 2016 (UTC)

I will quote "One of the wartime discoveries that provided an impetus for the post-war focus on radio astronomy was the independent detection of solar radio emission in Denmark (Schott, 1947), the United States (Reber, 1944; Southworth, 1945), England (Hey, 1946), Australia (Orchiston and Slee, 2002) and New Zealand. This paper is about Elizabeth Alexander’s investigation of solar radio emission in New Zealand during 1945." Emphasis mine. Now stop it with your hissy fit.Headbomb {talk / contribs / physics / books} 20:55, 25 February 2016 (UTC)

Those are, quite obviously, the authors and dates of publication of the relevant articles, as found in the references on pages 90-92. "Bob and Mary, 1983" in this context means "the thing written by both Bob and Mary, that was published in 1983." It's a very, very common scholarly convention. Anmccaff (talk) 21:06, 25 February 2016 (UTC)

How are distances to radio sources estimated

Article does not seem to explain how the distances to various types of radio sources are or were determined, eg. is the doppler effect/red shift of radio spectral lines used ? How much is the Dispersion measure used (for pulsars and other objects) ? To what extent is finding an optical counterpart used ?- Rod57 (talk) 10:53, 15 February 2020 (UTC)

Many methods. Sometimes the object being studied is visible in optical spectrum, sometimes not. It might be determined from red shift in optical or radio spectrum, or using other methods (i.e. supernova explosions, variability of star and its apparent luminosity, etc). Rearly radio source distance can be determined just using radio methods, but sometimes it is. 2A02:168:2000:5B:3442:E8AB:99EF:2444 (talk) 13:44, 23 March 2021 (UTC)

Space-based VLBI

Should the VLBI section of the article include a mention of the emerging space- based VLBI? It may be relevant to discuss developing possibilities in radio astronomy technology.Audrey Buck (talk) 23:10, 5 September 2020 (UTC)

On This Day In Space: Jan. 10, 1946: Radio astronomy is born

Hello to all ! As in subject, according to what space.com here says (i wish that the url is absolute), the project Diana by U.S. army in 1946 declare the born of radio astronomy. why isn't even the project mentioned in the page ? Windino [Rec] 22:28, 10 January 2023 (UTC)

Interesting, but wrong. Radio astronomy was born with Jansky's announcement in April 1933. And Grote Reber was doing systematic radio astronomy by 1937. Fountains of Bryn Mawr (talk) 22:44, 10 January 2023 (UTC)