Radiation astronomy/First radio source in Pisces

The first radio source in Pisces is unknown.

The image shows 54 Piscium, its red dwarf companion and a Saturn-sized planet. One of these may be a radio source. Credit: NASA / JPL-Caltech / T. Pyle (SSC).{{free media}}

The field of radio astronomy is the result of observations and theories about radio sources detected in the sky above.

The first astronomical radio source discovered may have been the Sun.

But, radio waves from the Sun are intermingled with other radiation so that the Sun may appear as other than a primary source for radio waves.

The early use of sounding rockets and balloons to carry radio detectors high enough may have detected radio waves from the Sun as early as the 1940s.

This is a lesson in map reading, coordinate matching, and researching. It is also a research project in the history of radio astronomy looking for the first astronomical radio source discovered in the constellation of Pisces.

Nearly all the background you need to participate and learn by doing you've probably already been introduced to at a secondary level and perhaps even a primary education level.

Some of the material and information is at the college or university level, and as you progress in finding radio sources, you'll run into concepts and experimental tests that are actual research.

If stellar flares have origins similar to solar flares, then flare stars produce radio waves.

First stepEdit

The first step is to succeed in finding a radio source in Pisces.

Next, you'll need to determine the time stamp of its discovery and compare it with any that have already been discovered.

Over the history of radio astronomy a number of sources have been found, many as point sources in the night sky. These points are located on the celestial sphere using coordinate systems. Familiarity with these coordinate systems is not a prerequisite. Here the challenge is geometrical, astrophysical, and historical. The coordinates are usually supplied by the radio source observers.


Def. a natural source usually of radiation in the sky especially at night is called an astronomical source.

A source of astronomical information on older detections of radio sources is included in the Science section of the lecture/article radio astronomy.

Traveling radio sourcesEdit

Many radio sources do not remain in a constellation for lengthy periods. Some of these are the Sun and sources apparently in orbit around the Sun. The Sun travels through the 13 constellations along the ecliptic (the plane of the Earth's orbit around the Sun): the 12 of the Zodiac and the constellation Ophiuchus. These are described in source astronomy.


To introduce yourself to some aspects of the challenge may I suggest reading the highlighted links mentioned above, and if you're curious, those listed under the section "See also" below.

Radio waves are a form of radiation that is currently part of electromagnetic radiation intersecting the Earth. More information about radiation is in radiation astronomy.


This is an image of the International Astronomical Union (IAU) sky map of the constellation Pisces. Credit: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg).
Pisces is in Hevelius' map (1690). Credit: .

The Wikipedia article about the constellation Pisces contains a high school level description. The figure at right shows the sky map of Pisces. Around the edges of the map are coordinates related to longitude and latitude, but with the Earth rotating on its axis every 24 hours the celestial coordinates must remain fixed relative to the background light sources in the sky.

Pisces is a constellation of the zodiac. Its name is the Latin plural for fish.

The Vernal equinox is currently located in Pisces, due south of ω Psc, and, due to precession, slowly drifting below the western fish towards Aquarius.

The shape, size, and to some extent its location as a constellation has changed over time. The second figure at right is an earlier version.

Pisces originates from some composition of the Babylonian constellations Šinunutu4 "the great swallow" in current western Pisces, and Anunitum the Lady of the Heaven, at the place of the northern fish. In the first Millennium BCE texts known as the Astronomical Diaries, part of the constellation was also called DU.NU.NU (Rikis-nu.mi, "the fish cord or ribbon").[1]

Pisces is associated with Aphrodite and Eros, the who escaped from the monster Typhon by leaping into the sea and transforming themselves into fish.[2] In order not to lose each other, they tied themselves together with rope. The Romans adopted the Greek legend, with Venus and Cupid acting as the counterparts for Aphrodite and Eros. The knot of the rope is marked by Alpha Piscium (α Psc), also called Al-Rischa ("the cord" in Arabic).

In 1690, the astronomer Johannes Hevelius in his Firmamentum Sobiescianum regarded the constellation Pisces as being composed of four subdivisions:[3]

  • Piscis Boreus (the North Fish): σ – 68 – 65 – 67 – ψ1 – ψ2 – ψ3 – χ – φ – υ – 91 – τ – 82 – 78 Psc.
  • Linum Boreum (the North Cord):[3] χ – ρ,94 – VX(97) – η – π – ο – α Psc.
  • Linum Austrinum (the South Cord):[3] α – ξ – ν – μ – ζ – ε – δ – 41 – 35 – ω Psc.
  • Piscis Austrinus (the South Fish):[3] ω – ι – θ – 7 – β – 5 – κ,9 – λ – TX(19) Psc.

In 1754, the astronomer John Hill proposed to treat part of Pisces as a separate constellation, called Testudo (the Turtle)[4] 24 – 27 – YY(30) – 33 – 29 Psc.,[5] centred a natural but faint asterism in which the star 20 Psc is intended to be the head of the turtle. However the proposal was largely neglected by other astronomers with the exception of Admiral Smyth, who mentioned it in his book The Bedford Catalogue, and it is now obsolete.[6]

The stars of Pisces were incorporated into several constellations in Chinese astronomy. Wai-ping ("Outer Enclosure") was a fence that kept a pig farmer from falling into the marshes and kept the pigs where they belonged. It was represented by Alpha, Delta, Epsilon, Zeta, Mu, Nu, and Xi Piscium. The marshes were represented by the four stars designated Phi Ceti. The northern fish of Pisces was a part of the House of the Sandal, Koui-siou.

Also, in the Wikipedia article is a list of stars in Pisces.

Searching catalogsEdit

In the lecture/article radio astronomy in its science section is a list of older catalogs of radio sources. Using the constellation description in the previous section and the range of coordinates for the constellation in source astronomy, scan through the coordinates for these radio sources to see if any may be within Pisces.

If you find any that are, skip down to the section Radio sources in Pisces and make an entry. Be sure to check the coordinate era, most B1950 coordinates have changed slightly to the new J2000 set. Try the catalog designation at either SIMBAD website.

Testing a sourceEdit

There are many web sites that may have an radio source listed for the constellation Pisces. Some that you may wish to try are in the External links section near the bottom of this lesson.

Wikipedia sourcesEdit

A. Constellation article

Under "Notable features" in the Wikipedia article on the constellation Pisces is the list of stars in Pisces. Click on this link. In the table of this Wikipedia article is α Psc. To the right are coordinates:

Right ascension (RA): 02h 02m 02.81972s and Declination (Dec): +02° 45' 49.5410".

Find these coordinates on the Pisces map at the right.

To evaluate the star as a radio source, skip ahead to section "Radio sources".

B. Wikipedia search

Another way to look for radio sources in the constellation is to perform a search on Wikipedia. Try "radio pisces" without the quotes. This yields 134 returns which include an outline of astronomy, several musical groups, and many entries that mention Pisces and radio.

The outline of astronomy names no radio sources.

Scroll down the list of 134 looking for some clear text stating that a radio source in Pisces is discussed, like NGC 383.

When you find one, skip ahead to the section "Radio sources".

SIMBAD sourcesEdit

Another way to find possible radio sources in Pisces is to use search queries on SIMBAD.

Click on either SIMBAD link under "External links" below, then click on "Criteria query", or "by criteria".

In the tan box, type in "region(02 02 02.820 +02 45 49.54,10m)", without the quotes. This tells the SIMBAD computer you are interested in a circular region of the celestial sphere centered on the coordinates for alpha Piscium, with a radius of 10 arcminutes (10m), or try 10d for 10 degrees.

Notice on the page over at the right from the tan colored box: "Return". The default is "object count". Click on "submit query". In a few moments a result something like "Number of objects: 6" should appear. Click "Back" to see the tan box again.

Adding an object type such as & otype='Rad' to the region request reduces the returned number to those that are radio sources, zero within 10 m of alpha Piscium. Using 10d instead with & otype='Rad' yields 4882 radio sources But, all of the otypes listed at Object classification in SIMBAD may contain radio stars, but may not state that any are radio sources. Other otypes of radio sources include Rad (radio-source), mR (metric radio-source), cm (centrimetric radio-source), mm (millimetric radio-source), smm (sub-millimetric source), HI (HI (21 cm) source, rB (radio burst), rG (radio galaxy), or Mas (maser).

The SIMBAD criteria search allows you to specify spectral types for possible stars. The criteria "sptype" (the exact spectral type): returns only the objects having the requested spectral type (i.e. sptype = 'k0' does not return 'K0III',...). And, "sptypes" should be used to retrive all objects having a spectral type containing the one specified; i.e., sptypes = 'K0' will return all objects having 'K0' as a spectral type, but also 'K0III' or 'K0IIIp', ...). This may also be comgined using an "&" to pick sources you might like.

Here again no information about possible radio sources may be listed. You have to click on one of objects in the list.

If a flare star is a likely source of radio waves, which it may because flares also generate radio rays, then entering otype='Fl*' should locate likely radio sources.

Using only otype='Fl*' on SIMBAD yields 2582 in all of SIMBAD.

SAO/NASA Astrophysics Data SystemEdit

In the naming of sources per constellation, the genitive is in common use. For Pisces, the genitive is Piscium.

Click on the SAO/NASA Astrophysics Data System link below in the "External links". Try "Pisces radio waves" without the quotes, or "alpha piscium" with quotes, followed by radio. The first returns eight primary source articles that may contain radio sources in Pisces. The second returns zero.

Click on a link below # Bibcode Authors. If the Abstract describes the detection of radio waves from a source in the constellation Pisces, go to the next section under "SAO/NASA Astrophysics Data System".

If it does not try another bibcode link.

Radio sourcesEdit

There are several ways to evaluate a radio source for the constellation Pisces.

Wikipedia sourcesEdit

Click on the link to the Wikipedia article. After you've enjoyed reading about the source, use the 'find' command of your browser to see if this Wikipedia page mentions anything about radio waves. Does the article mention whether or not the source is a radio source?

What is the current time stamp for the Wikipedia article on the source? [Hint]: look for something like "This page was last modified on 25 December 2013 at 20:12." very near the bottom of the page. For now this is an adequate time stamp.

From reading the Wikipedia article on the source, if you believe the text demonstrates that the source is not a radio source in Pisces edit the "Non-radio sources in Pisces" section near the bottom of the page with an entry similar to "# Alpha Piscium 25 December 2013 at 20:12 Wikipedia article "Alpha Piscium", without the quotes, and finish the entry with four "~"s without the quotes after the period. The date included with your designation or username is a time stamp for the entry. The last portion of the entry is the source of your information.

On the other hand, if there are one or more sentences in the article that you believe demonstrates that the source is a radio source in Pisces edit the section below "Radio sources in Pisces" with a similar entry.

Go to the section entitled, "Challenging an entry".

The Wikipedia article on Alpha Piscium mentions, "Alpha Piscium [...] is a spectroscopic binary star system with components that orbit each other every 3848.8 days (10.5 years).[7] The combined stellar classification of the system is K0.5 IIIb,[8] which matches the spectrum of a lower luminosity giant star."

From the lecture/article on radio astronomy, the radio radiation band may not have an appropriate wavelength temperature pair.

Is the primary star of alpha Piscium a radio star, or a radio source?

Wikimedia commonsEdit

Another possible website for radio sources is Wikimedia Commons. Try entering "radio Pisces" without the quotes.

This returns the one image at the top of the page.

SIMBAD sourcesEdit

To check any source (even one from Wikipedia) on SIMBAD, click of the "External link" to the "SIMBAD Astronomical Database".

At the lower right side of the SIMBAD Astronomical Database page is a "Basic search" box. There are several ways to try your target:

  1. source name: without the quotes or
  2. source coordinates: without the quotes, for example, "02 02 02.820 +02 45 49.54".

If you are looking at a SIMBAD generated table which lists possible targets, click on one.

Having SIMBAD list all of its 2582 flare stars produces an apparently formidable task. Try searching with your browser using "Psc".

Many of the flare stars listed do not include a constellation designation. Letting SIMBAD plot all of these flare stars and comparing the plot with the constellation sky chart may help.

There are 3511 otype='Rad' listed in SIMBAD. Plotting them may be helpful or scanning them using +2 with your browser may eventually reveal at least one radio source.

If you have already found a radio source (or a table of them) using SIMBAD, click on the blue link identifier for the first to look for the date of observations.

SIMBAD time stampEdit

Peruse the SIMBAD page for a time stamp or date of last revision. [Hint: it may look something like "2012.01.09CET20:10:02" and be in the upper right.]

If the entry at SIMBAD convinces you that the source is not a radio source, edit the "Non-radio sources in Pisces" section near the bottom of this page and type in an entry similar to "# Source Name 2012.01.09CET20:10:02 SIMBAD article "SIMBAD source name".", without the first set of quotes, followed by four ~s.

If your SIMBAD analysis convinces you that you may have found a radio source in Pisces (did you check the coordinates vs. the map of Pisces?), make an entry something like the ones in the section "Radio sources in Pisces".

SAO/NASA Astrophysics Data System sourcesEdit

If the abstract states that a radio source in Pisces is detected or studied, consider entering it in the section "Radio sources in Pisces" below.

Abstract time stampEdit

On the abstract page is a Publication Date:. This may serve as a time stamp for establishing that the source is detected as a radio source on or before the date of publication. The time stamp followed by four ~s for your verification as determiner in the section "Radio sources in Pisces" completes your entry.

Challenging an entryEdit

Any entry in either the section "Radio sources in Pisces" or "Non-radio sources in Pisces" can be challenged. The time stamp can be challenged to see if there is an earlier one. The source can be challenged by an earlier source.

Wikipedia challengesEdit

Is Wikipedia a 'primary source', or does the Wikipedia article cite a source?

Even though Wikipedia has an article on the source, is it a good place to stop in testing whether the source has been detected as an astronomical radio source?

If the Wikipedia article cites a primary source, skip down to the section on "Primary sources".

SIMBAD challengesEdit

Is SIMBAD a 'primary source'?

SIMBAD is an astronomical database provided by the Centre de Données astronomiques de Strasbourg. It is an authoritative source, but they do occasionally make a mistake.

If you find a radio source within the constellation on SIMBAD, the next step is to find the earliest time stamp of discovery.

SAO/NASA Astrophysics Data System challengeEdit

Is the SAO/NASA Astrophysics Data System abstract entry a primary source?

The SAO/NASA Astrophysics Data System is an astronomical database provided by the High Energy Astrophysics Division at the Harvard-Smithsonian Center for Astrophysics of Harvard University. The abstract has been copied from the actual article in a scientific journal or other publication. Mistakes can be made and the article may record within its text exact dates when the observation or detection of radio waves actually occurred. Such a record may provide an earlier time stamp.

Primary sourcesEdit

Primary sources may be searched for possible additional information perhaps not yet evaluated by SIMBAD or not presented in a Wikipedia article about a source.

Wikipedia test sourcesEdit

For a Wikipedia article that cites a primary source, scroll down to the reference and open the reference. Read through the article looking for where the source mentioned in the Wikipedia article occurs. Some primary source authors may use source designations that are not mentioned in the Wikipedia article. To look for other designations, click on the link to SIMBAD in the "External links" on this page, enter the source name from the Wikipedia article, and see if other names are mentioned in the article.

When none of the names are mentioned, click on the link for "Google Advanced Search" in the list of "External links", enter the source name or designation(s) such as "Gliese 866", with radio waves to see if the source has a reference indicating it is a radio source source. And, look for the earliest one. Compose an entry using the primary source.

SIMBAD test sourcesEdit

Further down the SIMBAD page is a list of "Identifiers". Click on the blue bold portion.

On the page that appears should be a primary source listed after Ref:. Click on the blue link with the oldest year. This yields an earlier time stamp and entry citation like the current one in the section "Radio sources in Pisces". If you find another source or an earlier time stamp, compose a similar entry and edit the section. Additional information to add into the reference can be found by clicking on "ADS services" from the SIMBAD page.

SAO/NASA Astrophysics Data System sources testEdit

Click on either the "Electronic Refereed Journal Article (HTML)" or "Full Refereed Journal Article (PDF/Postscript)", if available.

Depending on the article display, if the abstract is repeated and the article is listed as FREE, click on either the PDF or HTML version.

While scanning or reading the article look for "Observations" (or use the Find function of your browser) and the possible inclusion of dates for these. If more than one radio source in Pisces are detected, which one(s) would you list in the section "Radio sources in Pisces" below?

An example of an article reference is provided in that section.

Changing an entryEdit

From your analysis of the source so far, is it a radio source?

If you have found an earlier time stamp for the source than the one listed in the section below "Non-radio sources in Pisces" and the answer to the above question is "no", you can edit the section with your result. Or, you can leave the entries as is and try another star.

If you have found an earlier time stamp for the source than the one listed in the section below "Radio sources in Pisces", edit the section with your result. Or, if you found another radio source with a comparable or earlier time stamp, edit the section with your result.

Radio sources in PiscesEdit

  1. NGC 383 states, "NGC 383 is a double radio galaxy[3] with a quasar-like appearance located in the constellation Pisces. [...] Recent discoveries by the National Radio Astronomy Observatory in 2006 reveal that NGC 383 is being bisected by high energy relativistic electrons traveling at relatively high fractions of the speed of light. These relativistic electrons are detected as synchrotron radiation in the x-ray and radio wavelengths. The focus of this intense energy is the galactic center of NGC 383. The relativistic electron jets detected as synchrotron radiation extend for several thousand parsecs and then appear to dissipate at the ends in the form of streamers or filaments." The reference [3] is SIMBAD. This link is good and SIMBAD confirms that NGC 383 is a radio galaxy. The primary source article has bibcode=1992MNRAS.254..655P. It is a catalog of 800 compact radio sources. The observations were carried out between February 19 and 23, 1990. --Marshallsumter (discusscontribs) 22:25, 27 February 2014 (UTC)

Non-radio sources in PiscesEdit

Oldest recordEdit

NGC 383 and SIMBAD confirms that NGC 383 is a radio galaxy. The primary source article has bibcode=1992MNRAS.254..655P. It is a catalog of 800 compact radio sources. The observations were carried out between February 19 and 23, 1990.

SIMBAD annotationsEdit

For any particular source, the SIMBAD record may indicate that it is not a radio source yet above you may have found at least two refereed journal articles to indicate that it is. Use the second SIMBAD External links to directly display the SIMBAD database in France.

Enter the name source you have found into the search box. Scroll down to the Annotations :. Look for the link "add an annotation to this object". With browser open to the literature citations available, click on this link. You may need to register as a user. It's free. Post your annotation containing the literature references.


  1. The first radio source in Pisces may have been found in the 20's.

See alsoEdit


  1. Origins of the ancient constellations: I. The Mesopotamian traditions by J. H. Rogers 1998, page 19 page 19 (table 3, rows 2-3) and page 27
  2. P.K. Chen, A Constellation Album: Stars and Mythology of the Night Sky, p. 94 (2007, ISBN 978-1931559386).
  3. 3.0 3.1 3.2 3.3 Johannes Hevelius, (1690) Firmamentum Sobiescianum, Leipzig, Fig.NN
  4. Richard Hinckley Allen (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York City, New York: Dover Publications Inc.. p. 163 342. ISBN 978-0-486-21079-7. 
  5. Ciofi, C., Torre, p., Costellazioni Estinte (nate dal 1700 al 1800): Sezione di Ricerca per la Cultura Astronomica
  6. Smyth, W. H., (1884) The Bedford Catalogue
  7. S. Jancart, A. Jorissen, C. Babusiaux, D. Pourbaix (October 2005). "Astrometric orbits of SB^9 stars". Astronomy and Astrophysics 442 (1): 365–80. doi:10.1051/0004-6361:20053003. 
  8. R. O. Gray, C. J. Corbally, R. F. Garrison, M. T. McFadden, E. J. Bubar, C. E. McGahee, A. A. O'Donoghue, E. R. Knox (July 2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample". The Astronomical Journal 132 (1): 161–70. doi:10.1086/504637. 

External linksEdit

{{Principles of radiation astronomy}}