Radiation astronomy/First superluminal source in Indus

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This is an Aladin at SIMBAD image of ICRF J230343.5-680737, a Seyfert 1 galaxy in the constellation Indus. Credit: Aladin at SIMBAD.

The first superluminal source in Indus is unknown.

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

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

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

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

This is a lesson in map reading, coordinate matching, and searching. It is also a project in the history of superluminal astronomy looking for the first astronomical superluminal source discovered in the constellation of Indus.

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 superluminal sources, you'll run into concepts and experimental tests that are an actual search.

First step[edit]

Main sources: Step/First and First step

The first step is to succeed in finding a superluminal, or possible superluminal, source in Indus.

As superluminal, or possible superluminal, sources may be rather rare, a first place to look is superluminal astronomy. Compare sources mentioned in the lecture with SIMBAD coordinates for the source and the constellation figure to see if it is in the constellation. For example, the quasar 3C 273 at J2000.0 RA 12 29 06.695 Dec +02 03 08.66 is not. Nor is 3C 380 (also known as 2C 1569, 4C 48.46, 6C 182813+484244), or 3C 345.

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 superluminal 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 superluminal source observers.

Astronomical sources[edit]

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 superluminal sources is included in the Science section of the lecture/article superluminal astronomy.

Traveling superluminal sources[edit]

Many superluminal sources do not remain in a constellation for lengthy periods. Some of these are or may be associated with 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.

Backgrounds[edit]

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.

Superluminal rays are a form of radiation that is currently part of the radiation intersecting the Earth. More information about radiation is in radiation astronomy.

Constellations[edit]

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

The Wikipedia article about the constellation Indus contains a high school level description. The figure at top right shows the sky map of Indus. 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.

"The constellation was one of twelve created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman[1] and it first appeared on a 35-cm diameter celestial globe published in 1597 (or 1598) in Amsterdam by Plancius with Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in Johann Bayer's Uranometria of 1603.[2][3] Plancius portrayed the figure as a nude male with arrows in both hands but no bow.[4]"[5]

The shape, size, and to some extent its location as a constellation has changed over time.

Also, in the Wikipedia article is a list of stars in Indus. As most superluminal sources may not be stars, checking the constellation entry for notable sources may be more productive.

Searching catalogs[edit]

Main sources: Sciences/Catalogs and Catalogs

In the lecture/article superluminal astronomy in its science section is a list of older catalogs of superluminal 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 superluminal sources to see if any may be within Indus.

If you find any that are, skip down to the section Superluminal sources in Indus 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 source[edit]

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

Wikipedia sources[edit]

A. Constellation article

Under "Notable features" in the Wikipedia article on the constellation Indus is the list of stars in Indus. Click on this link. In the table of this Wikipedia article is alpha Indi (α Ind). To the right are coordinates:

Right ascension (RA): 20h 37m 34.032s and Declination (Dec): -47° 17' 29.40".

Find these coordinates on the Indus map at the right.

To evaluate the star as a superluminal source, skip ahead to section Superluminal sources.

B. Wikipedia search

Another way to look for superluminal sources in the constellation is to perform a search on Wikipedia. Try "superluminal indus" without the quotes. This yields 1 return which is Sagittarius (constellation). Trying "superluminal" yields 176 entries.

Scroll down the list for some clear text stating that a superluminal source in Indus is discussed.

If you find one, skip ahead to the section Superluminal sources.

SIMBAD sources[edit]

Another way to find possible superluminal sources in Indus 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 "otype='QSO' & region(polygon FK5,00 00 00.0 -40.0,20 00 00.0 -40.0,20 00 00.0 -75.0,00 00 00.0 -75.0)", without the quotes. This tells the SIMBAD computer you are interested in a polygonal region of the celestial sphere around on the coordinates for the constellation Indus.

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: 619" should appear. Click "Back" to see the tan box again.

Adding an object type such as & otype='QSO' to the region request reduces the returned number to those that are, or may be, superluminal sources in a polygon around Indus. But, all of the otypes listed at Object classification in SIMBAD may contain superluminal entities, sources, or objects, yet may not state that any are superluminal sources.

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 superluminal sources may be listed. You have to click on one of objects in the list.

If a flare source is a likely source of superluminal rays, which it may because flares on a galactic scale may also generate superluminal rays, then entering otype='Fl*' should locate likely superluminal sources.

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

Other otypes such as Seyfert galaxies (otype='Sy1', 'Sy2', AGN, for example) or supernovae (otype='SN') may provide superluminal, or potential superluminal, sources.

SAO/NASA Astrophysics Data System[edit]

In the naming of sources per constellation, the genitive is in common use. For Indus, the genitive is Indi.

Click on the SAO/NASA Astrophysics Data System link below in the External links. Try "Indus superluminal waves" without the quotes, "Indus superluminal", or "superluminal indi" with quotes, followed by superluminal. The first returns 0 primary source articles that may contain superluminal sources in Indus. The second and third return 0. But, "superluminal" returns 5451 abstracts.

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

If it does not try another bibcode link.

Superluminal sources[edit]

There are several ways to evaluate a superluminal source for the constellation Indus.

Wikipedia sources[edit]

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 superluminal rays. Does the article mention whether or not the source is a superluminal 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 superluminal source but the source is in Indus edit the Non-superluminal sources in Indus section near the bottom of the page with an entry similar to "# Alpha Indi 25 December 2013 at 20:12 Wikipedia article "Alpha Indi", 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 superluminal source in Indus edit the section Superluminal sources in Indus with a similar entry.

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

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

Is the primary star of alpha Indi a superluminal star, or a superluminal source?

Wikimedia commons[edit]

Another possible website for superluminal sources is Wikimedia Commons. Try entering "superluminal Indus" without the quotes.

Using "superluminal' without the quotes alone yields no images.

SIMBAD sources[edit]

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 "Ind".

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 156816 otype='QSO' listed in SIMBAD. Plotting them may be helpful or scanning them using +2, per the example, with your browser may eventually reveal at least one superluminal source.

If you have already found a superluminal 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 stamp[edit]

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 superluminal source, edit the Non-superluminal sources in Indus 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 superluminal source in Indus (did you check the coordinates vs. the map of Indus?), make an entry something like the ones in the section Superluminal sources in Indus.

SAO/NASA Astrophysics Data System sources[edit]

If the abstract states that a superluminal source in Indus is detected or studied, consider entering it in the section Superluminal sources in Indus below.

Abstract time stamp[edit]

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

Challenging an entry[edit]

Any entry in either the section Superluminal sources in Indus or Non-superluminal sources in Indus 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 challenges[edit]

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 superluminal source?

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

SIMBAD challenges[edit]

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 superluminal source within the constellation on SIMBAD, the next step is to find the earliest time stamp of discovery.

SAO/NASA Astrophysics Data System challenge[edit]

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 superluminal rays actually occurred. Such a record may provide an earlier time stamp.

Primary sources[edit]

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 sources[edit]

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 superluminal rays to see if the source has a reference indicating it is a superluminal source source. And, look for the earliest one. Compose an entry using the primary source.

SIMBAD test sources[edit]

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 Superluminal sources in Indus. 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 test[edit]

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 superluminal source in Indus are detected, which one(s) would you list in the section Superluminal sources in Indus below?

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

Changing an entry[edit]

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

If you have found an earlier time stamp for the source than the one listed in the section below Non-superluminal sources in Indus 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 Superluminal sources in Indus, edit the section with your result. Or, if you found another superluminal source with a comparable or earlier time stamp, edit the section with your result.

Superluminal sources in Indus[edit]

  1. ICRF J230343.5 680737, a Seyfert 1 galaxy is mentioned on the website, url=rorf.usno.navy.mil/ICRF/ICRFpaper.ps as is the phrase "superluminal motions", but this does not as yet confirm that ICRF J230343.5 680737 has superluminal motions associated with it. It may only have the high possibility of such motion nearby.

Non-superluminal sources in Indus[edit]

Oldest record[edit]

SIMBAD annotations[edit]

For any particular source, the SIMBAD record may indicate that it is not a superluminal 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.

Hypotheses[edit]

Main source: Hypotheses
  1. The first superluminal source in Indus has been discovered since 50 b2k.

See also[edit]

References[edit]

  1. Ian Ridpath and Wil Tirion (2001). Stars and Planets Guide. Princeton University Press. pp. 162-163. ISBN 0-691-08913-2. 
  2. Michael E. Bakich (1995). The Cambridge Guide to the Constellations. Cambridge University Press. ISBN 0-521-44921-9. 
  3. Helen Sawyer Hogg (1951). "Out of Old Books (Pieter Dircksz Keijser, Delineator of the Southern Constellations)". Journal of the Royal Astronomical Society of Canada 45: 215. 
  4. Richard Hinckley Allen (1963). Star Names, Their Lore and Meaning. New York: Dover Publications. ISBN 0-486-21079-0. 
  5. "Indus (constellation), In: Wikipedia". San Francisco, California: Wikimedia Foundation, Inc. February 15, 2014. Retrieved 2014-03-14. 

External links[edit]

{{Astronomy resources}}{{Principles of radiation astronomy}}