Radiation astronomy/First submillimeter source in Carina

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Observations made with the APEX telescope reveal the cold dusty clouds from which stars form. Credit: ESO/APEX/T. Preibisch et al. (Submillimetre); N. Smith, University of Minnesota/NOAO/AURA/NSF (Optical).

The first submillimeter source in Carina is unknown.

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

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

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

The early use of sounding rockets and balloons to carry submillimeter detectors high enough may have detected submillimeter 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 submillimeter astronomy looking for the first astronomical submillimeter source discovered in the constellation of Carina.

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 submillimeter sources, you'll run into concepts and experimental tests that are actual research.

First step[edit]

Main sources: Step/First and First step

The first step is to succeed in finding a submillimeter source in Carina.

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 submillimeter 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 submillimeter source observers.

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

Traveling submillimeter sources[edit]

Many submillimeter 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.

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.

Submillimeter waves are a form of radiation that is currently part of electromagnetic 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 Carina. Credit: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg).
Carina is in Hevelius' map (1690). Credit: Johannes Hevelius.

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

"Carina [the Keel ...] was formerly part of the larger constellation of Argo Navis (the ship Argo) until that constellation was divided [in 1763] into three pieces, the other two being Puppis (the poop deck), and Vela (the sails of the ship)."[1]

The Argo Navis constellation [at second right] is from Uranographia by Johannes Hevelius in 1690. The view is mirrored following the tradition of celestial globes, showing the celestial sphere in a view from "outside".

"Argo Navis is the only one of the 48 constellations listed by the 2nd century astronomer Ptolemy that is no longer officially recognized as a constellation."[2]

"The Maori had several names for what was the constellation Argo, including Te Waka-o-Tamarereti, Te Kohi-a-Autahi, and Te Kohi.[3]"[2]

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.

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

Catalogs[edit]

Main sources: Sciences/Catalogs and Catalogs

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

If you find any that are, skip down to the section Submillimeter sources in Carina 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 submillimeter source listed for the constellation Carina. 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 Carina is the list of stars in Carina. Click on this link. In the table of this Wikipedia article is Canopus (α Car). To the right are coordinates:

Right ascension (RA): 06h 23m 57.09s and Declination (Dec): -52° 41' 44.6".

Find these coordinates on the Carina map at the right.

To evaluate the star as a submillimeter source, skip ahead to section "Submillimeter sources".

B. Wikipedia search

Another way to look for submillimeter sources in the constellation is to perform a search on Wikipedia. Try "submillimeter carina" without the quotes. This yields 7 returns which include the Hubble Space Telescope, several submillimeter telescopes, and several entries that mention Carina and submillimeter.

Scroll down the list of 7 looking for some clear text stating that a submillimeter source in Carina is discussed, like HD 95086 b.

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

SIMBAD sources[edit]

Another way to find possible submillimeter sources in Carina 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(06 23 57.09 -52 41 44.6,10m)", 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 Carinae, or Canopus, 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: 3" should appear. Click "Back" to see the tan box again.

Adding an object type such as & otype='smm' to the region request reduces the returned number to those that are submillimeter sources, zero within 10 m of alpha Carinae. Using 10d instead with & otype='smm' yields 19 submillimeter sources. But, all of the otypes listed at Object classification in SIMBAD may contain submillimeter stars, yet may not state that any are submillimeter 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 submillimeter sources may be listed. You have to click on one of objects in the list.

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

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

SAO/NASA Astrophysics Data System[edit]

In the naming of sources per constellation, the genitive is in common use. For Carina, the genitive is Carinae.

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

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

If it does not try another bibcode link.

Submillimeter sources[edit]

There are several ways to evaluate a submillimeter source for the constellation Carina.

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 submillimeter waves. Does the article mention whether or not the source is a submillimeter 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 submillimeter source in Carina edit the "Non-submillimeter sources in Carina" section near the bottom of the page with an entry similar to "# Alpha Carinae 25 December 2013 at 20:12 Wikipedia article "Alpha Carinae", 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 submillimeter source in Carina edit the section below "Submillimeter sources in Carina" with a similar entry.

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

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

Is the primary star of alpha Carinae a submillimeter star, or a submillimeter source?

Wikimedia commons[edit]

Another possible website for submillimeter sources is Wikimedia Commons. Try entering "submillimeter Carina" without the quotes.

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

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 "Car".

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 10336 otype='smm' 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 submillimeter source.

If you have already found a submillimeter 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 submillimeter source, edit the "Non-submillimeter sources in Carina" 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 submillimeter source in Carina (did you check the coordinates vs. the map of Carina?), make an entry something like the ones in the section "Submillimeter sources in Carina".

SAO/NASA Astrophysics Data System sources[edit]

If the abstract states that a submillimeter source in Carina is detected or studied, consider entering it in the section "Submillimeter sources in Carina" 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 submillimeter source on or before the date of publication. The time stamp followed by four ~s for your verification as determiner in the section "Submillimeter sources in Carina" completes your entry.

Challenging an entry[edit]

Any entry in either the section "Submillimeter sources in Carina" or "Non-submillimeter sources in Carina" 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 submillimeter 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 submillimeter 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 millimeter waves 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 submillimeter waves to see if the source has a reference indicating it is a submillimeter 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 "Submillimeter sources in Carina". 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 submillimeter source in Carina are detected, which one(s) would you list in the section "Submillimeter sources in Carina" 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 submillimeter source?

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

Submillimeter sources in Carina[edit]

  1. "Observations made with the APEX telescope in submillimetre-wavelength light at a wavelength of 870 µm reveal the cold dusty clouds from which stars form in the Carina Nebula. This site of violent star formation, which plays host to some of the highest-mass stars in our galaxy, is an ideal arena in which to study the interactions between these young stars and their parent molecular clouds."[4] "The APEX observations, made with its LABOCA camera, are shown here in orange tones, combined with a visible light image from the Curtis Schmidt telescope at the Cerro Tololo Interamerican Observatory. The result is a dramatic, wide-field picture that provides a spectacular view of Carina’s star formation sites. The nebula contains stars equivalent to over 25 000 Suns, and the total mass of gas and dust clouds is that of about 140 000 Suns."[4] The article is dated to November 16, 2011. --Marshallsumter (discusscontribs) 04:31, 15 March 2014 (UTC)

Non-submillimeter sources in Carina[edit]

Oldest record[edit]

SIMBAD annotations[edit]

For any particular source, the SIMBAD record may indicate that it is not a submillimeter 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 submillimeter source in Carina was probably discovered since 70 b2k.
  2. If stellar flares have origins similar to solar flares, then flare stars produce submillimeter waves.

See also[edit]

References[edit]

  1. "Carina (constellation), In: Wikipedia". San Francisco, California: Wikimedia Foundation, Inc. February 15, 2014. Retrieved 2014-03-14. 
  2. 2.0 2.1 "Argo Navis, In: Wikipedia". San Francisco, California: Wikimedia Foundation, Inc. February 7, 2014. Retrieved 2014-03-14. 
  3. Maud Worcester Makemson (1941). The Morning Star Rises: an account of Polynesian astronomy. Yale University Press. 
  4. 4.0 4.1 T. Preibisch et al. (November 16, 2011). "The Cool Clouds of Carina". ESO. Retrieved 2014-03-13. 

External links[edit]

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