Streaming Dark Nebulas near B44 (APOD 2009 June 15)

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Expand view Topic review: Streaming Dark Nebulas near B44 (APOD 2009 June 15)

Re: Streaming Dark Nebulas near B44 (APOD 2009 June 15)

by DavidLeodis » Thu Jun 18, 2009 7:22 pm

Thanks Case. Your post and annotated image were most helpful. :D
Case wrote:
DavidLeodis wrote:I'm not sure what is B44 in the image.
I think the center-top patch of dust in the APOD is the west end of Barnard 44. The very dense dust knots from the APOD, seem to extend from B 45, however, where the two dust lanes seem to meet (from our POV).
From what I was able to get from other sources, it looks like it isn't true that "one of the densest knots is B44, pictured near the bottom of the above image," as B44 is used to name the dark nebula from 22 Scorpii all the way to the bright Ophiuchus Milky Way. It seems that B44 is a streaming dark nebula.
Image
Edward Emerson Barnard (1857–1923) was a renowned observational astronomer. In 1887, Barnard joined the staff of Lick Observatory near San Jose, California. His achievements at Lick included the first photographic discovery of a comet; photographs of the Milky Way; and the discovery of Jupiter's fifth moon, Amalthea. In 1916 he discovered that the star cataloged as Munich 15040 in Ophiuchus had the fastest proper motion of any known star. This star has come to be known as Barnard's Star.
His great work, the Photographic Atlas of Selected Regions of the Milky Way, was published at Yerkes Observatory following his death in 1923. From this work, a list of roughly 350 Dark Nebulae, (known as "Barnard Objects") was extracted and cataloged.

Re: Streaming Dark Nebulas near B44 (APOD 2009 June 15)

by Case » Thu Jun 18, 2009 7:07 pm

DavidLeodis wrote:I'm not sure what is B44 in the image.
I think the center-top patch of dust in the APOD is the west end of Barnard 44. The very dense dust knots from the APOD, seem to extend from B45, however, where the two dust lanes seem to meet (from our POV).
From what I was able to get from other sources, it looks like it isn't true that "one of the densest knots is B44, pictured near the bottom of the above image," as B44 is used to name the dark nebula from 22 Scorpii all the way to the bright Ophiuchus Milky Way. It seems that B44 is a elongated streaming dark nebula, not a local knot.
Image
Edward Emerson Barnard (1857–1923) was a renowned observational astronomer. In 1887, Barnard joined the staff of Lick Observatory near San Jose, California. His achievements at Lick included the first photographic discovery of a comet; photographs of the Milky Way; and the discovery of Jupiter's fifth moon, Amalthea. In 1916 he discovered that the star cataloged as Munich 15040 in Ophiuchus had the fastest proper motion of any known star. This star has come to be known as Barnard's Star.
His great work, the Photographic Atlas of Selected Regions of the Milky Way, was published at Yerkes Observatory following his death in 1923. From this work, a list of roughly 350 Dark Nebulae, (known as "Barnard Objects") was extracted and cataloged.

Re: Streaming Dark Nebulas near B44 (APOD 2009 June 15)

by DavidLeodis » Tue Jun 16, 2009 12:15 pm

I'm not sure what is B44 in the image. The information brought up through the B44 link in the explanation indicates that B44 is a long dark dust stream whereas the explanation states B44 is a dense knot of dust near the bottom of the image (how near the bottom?). :?

Re: Streaming Dark Nebulas near B44

by neufer » Mon Jun 15, 2009 7:31 pm

saberard wrote:"Dark dust lit by the bright yellow star Antares highlight this photogenic starscape of the southern sky."
Simple verb-subject agreement is not rocket science; but I frequently see this sort of thing on this site. :?
"Dust" is almost always used as a descriptive term at APOD; it was probably "dust clouds" or "dust lanes" and the noun/subject got dropped for some reason (e.g., more than 140 words?).

http://antwrp.gsfc.nasa.gov/apod/ap040509.html
http://antwrp.gsfc.nasa.gov/apod/ap080603.html
http://antwrp.gsfc.nasa.gov/apod/ap080104.html
http://antwrp.gsfc.nasa.gov/apod/ap070911.html
http://antwrp.gsfc.nasa.gov/apod/ap070903.html

http://mysite.du.edu/~jcalvert/astro/magnitud.htm wrote:
Red giant YELLOW Antares, α Scorpii, is of spectral class M1, with T = 3000K. The wavelength spectral maximum occurs at 1700 nm, well in the infrared. The area corresponding to visual radiation is shown shaded, corresponding to 8.1% of the total.
Image
--------------------------------------------------------------------
The sun is spectral class G0, T=5750K, so the energy spectrum is as shown. The wavelength spectral maximum is at 890 nm, in the near infrared. The area corresponding to visual radiation is shown shaded, corresponding to 36.5% of the total.
Image
--------------------------------------------------------------------
Sirius is spectral class A0, and its temperature is 10,600K. Here, the visual radiation corresponds to the peak of the curve, with λmax = 480 nm. The area corresponding to visual radiation is shown shaded, corresponding to 30.8% of the total.
Image

Streaming Dark Nebulas near B44

by saberard » Mon Jun 15, 2009 5:15 pm

"Dark dust lit by the bright yellow star Antares highlight this photogenic starscape of the southern sky."
Simple verb-subject agreement is not rocket science; but I frequently see this sort of thing on this site. I encourage the learned writers to proof-read. Let's fight dumbing down, people! :?

Streaming Dark Nebulas near B44 (APOD 2009 June 15)

by neufer » Mon Jun 15, 2009 11:12 am

----------------------------------------------------------
B44 — The Restaurant at the End of the Universe

Make a reservation now:
B44 44 Belden Place
San Francisco, CA 94104

http://apod.nasa.gov/apod/ap090615.html
----------------------------------------------------------
http://en.wikipedia.org/wiki/Places_in_The_Hitchhiker%27s_Guide_to_the_Galaxy#Milliways wrote:
  • "Ladies and gentlemen," he said, "The Universe as we know it has now been in existence for over one hundred and seventy thousand million billion years and will be ending in a little over half an hour. So, welcome one and all to Milliways, the Restaurant at the End of the Universe!"
<<Milliways, also known as The Restaurant at the End of the Universe, can only be visited practically by time travel, as it exists at the end of time and matter. Marvin the Paranoid Android is one character who manages to reach Milliways without the use of time travel, merely by being very patient. One of the restaurant's major attractions is that diners can watch the entire universe end around them as they eat. The terminal moment is followed by dessert. Reservations are easily obtained, since they can be booked once the patron returns to his or her original time after their meal, and the restaurant's bill can be paid by depositing a penny in any bank account of the present time: by the end of the universe, Compound interest will be enough to pay the extremely high bill. Depending on when in Milliways timeline they visited, the diners' vehicles may have been parked by none other than Marvin the Paranoid Android. Near-instant transportation to the restaurant can be achieved in certain rarefied circumstances, such as being next to an exploding hyperspatial field generator on the planet where Milliways will eventually be built several billion years after the explosion occurs.

Among the items on the menu are various cuts of meat from the very obliging Ameglian Major Cow and the slightly less obliging vegetables in a green salad. While water and Aldebaran liqueurs are in stock, tea is not.

Because of the special number of impossibilities surrounding all aspects of Milliways, their advertising firm penned the following slogan: "If you've done six impossible things this morning, why not round it off with breakfast at Milliways—the Restaurant at the End of the Universe!" Believing "six impossible things before breakfast" is a quote of the White Queen's from Lewis Carroll's Through the Looking-Glass.

In the book form of the series, the visit to Milliways takes place in the novel The Restaurant at the End of the Universe. In the different versions of the story, Milliways is built on the ruins of either Magrathea or of Frogstar World B. In the twenty-sixth of the radio series, when many of the main characters meet at Milliways, Thor the thunder god asks that champagne be sent to Trillian, and in the process reveals that Arthur Dent and company are seated at Table 42.

The 2005 Hitchhiker's Guide to the Galaxy movie ends with a gag about the "The Restaurant at the End of the Universe" not being at the big bang end. According to The Salmon of Doubt, Douglas Adams came up with the idea while listening to Procol Harum's Grand Hotel.>>

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