Starship Asterisk*

Summer Triangles over Japan

Explanation: Have you ever seen the Summer Triangle? The bright stars Vega, Deneb, and Altair form a large triangle on the sky that can be seen rising in the early northern early spring during the morning and rising in the northern fall during the evening. During summer months, the triangle can be found nearly overhead near midnight. Featured here, the Summer Triangle asterism was captured last month from Gunma, Japan. In the foreground, sporting a triangular shape of its own, is a flowering 500 year old cherry tree, standing about 15 meters tall. The triangular shape of the asterism is only evident from the direction of Earth -- in actuality the stars are thousands of light years apart in space.

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it doesn't matter where in the entire universe the three stars are . . . they will always form a triangle unless in a straight line.

willi0000000 wrote:it doesn't matter where in the entire universe the three stars are . . . they will always form a triangle unless in a straight line.

Almost correct... There will be 6 lines of direction where only 2 stars of the stars will be visible, the third being hidden behind one of the other two.

I like the cherry tree. It made me wonder if the flavor of the cherries change over time with the age of the tree?

Beautiful photo. Thanks for the labeling. It helps a lot!

I find this photo really soothing and enchanting! I really like seeing cherry blossom trees, they're so delightful! Seeing the Summer Triangle in the photo makes me think what a telescopic widefield mosaic of the constellation of Aquila with Ha by Rogelio Bernal Andreo look like? Within the boundaries of Aquila are many planetary nebulae (including NGC 6781 and NGC 6778), supernova remnants (a few are W51 and W44), lots of dark nebulae (LDN 673 is a particular favourite of mine) as well as the exotic binary system SS 433.

I think it would be nice to lie on the ground under the cherry blossom tree with my future soulmate and look up at the stars together.

starsurfer wrote:I find this photo really soothing and enchanting! I really like seeing cherry blossom trees, they're so delightful! Seeing the Summer Triangle in the photo makes me think what a telescopic widefield mosaic of the constellation of Aquila with Ha by Rogelio Bernal Andreo look like? Within the boundaries of Aquila are many planetary nebulae (including NGC 6781 and NGC 6778), supernova remnants (a few are W51 and W44), lots of dark nebulae (LDN 673 is a particular favourite of mine) as well as the exotic binary system SS 433.

I think it would be nice to lie on the ground under the cherry blossom tree with my future soulmate and look up at the stars together.

I dunno. Somebody went a little overboard with the spiky fence there. They don't seem to want people near that tree.

I like the Summer Triangle. The three bright stars, Vega, Altair and Deneb, all belong to spectral class A and look so alike, and yet they are so dissimilar. First magnitude Altair, the second brightest-looking one of the stars at the end points of the Summer Triangle, is a modest star for its spectral class, only eleven times brighter than the Sun. Vega, the brightest-looking one and the (seemingly) bluest of the three, is almost fifty times brighter than the Sun and is seen pole on from the Earth, which means that we see deeper into its hot interior, making it look bluer. Distant Deneb, seemingly the puniest of them, is a true supergiant about fifty thousand times brighter than the Sun, with a radius about a hundred times that of the Sun. So if Deneb was to magically replace the Sun at the center of the solar system (thankfully, that is impossible), this white-hot supergiant would reach half-way from the center of the solar system to the Earth. Imagine!

Today's APOD is a very nice picture!

Ann

Cherry trees seem to garner "Fruits of the Lens" quite dramatically

http://www.boredpanda.com/sakura-cherry ... apan-2014/

"Fruits of Research" too

http://www.davidreneke.com/mysterious-g ... rry-tree/#

And they seem to be celebrated everywhere!!

http://www.emmettcherryfestival.com/

Guest wrote:

willi0000000 wrote:

APOD Robot wrote: Summer Triangles over Japan

<<The triangular shape of the asterism is only evident from the direction of Earth --
in actuality the stars are thousands of light years apart in space. >>

it doesn't matter where in the entire universe the three stars are . . . they will always form a triangle unless in a straight line.

Almost correct... There will be 6 lines of direction where only 2 stars of the stars will be visible,
the third being hidden behind one of the other two.

In the spirit of the curtailed APOD blurb:

• There are very few places in the Milky Way where luminous Deneb is prominently visible to the naked eye and also:
  
  • Where either faint Altair or Vega would be visible at all (much less that they should all appear
    to form a nice compact "near right angle" triangular asterism of comparably bright A stars).

    http://en.wikipedia.org/wiki/Summer_Triangle wrote:

    Code: Select all

    Name 	            Luminosity 	Distance(ly)  	Apparent magnitude 	Spectral type
    ------------------------------------------------------------------------------------------
    Deneb (Cygnus)	        70000	     3550 	             1.25  	         A2 
    Vega (Lyra)          	    52 	      25 	             0.03 	          A0
    Altair  (Aquila) 	        10  	     16.6 	           0.77              A7

In the case of any triangular asterism, a triangle can be viewed from ANY vantage point, not just earth! Only if one is looking at the three stars within their shared plane, or somewhere in the middle of the trio (where all are not visible at once) is a triangular asterism not visible.

Would be nice to point out that the entire field of view of the Kepler spacecraft is included in this image.... with hundreds (thousands?) of discovered solar systems, and many more...

I'd be curious to know if those attempting degrees in astronomy have a class in celestial coordinates. Maybe it's part of their math education. As it appears in the sky, the Summer Triangle appears as a scalene triangle with no equal sides and no equal angles. In truth the distance between Altair and Vega is about 15 light years https://ca.answers.yahoo.com/question/i ... 038AAFEAbB
with Deneb being somewhere around 1.5 to 4 thousand light years away making it, actually, closer to a very pointy isosceles triangle than as it appears in the sky from Earth.

Looking at the Summer Triangle it's hard to imagine the triangle's actual shape without plotting it on a three dimensional coordinate grid.

http://www.had2know.com/academics/trian ... nates.html

And this is why I question how astronomy students are taught coordinate systems? I don't know where to begin to in order to visualize the triangle's true shape within the boundaries of our galaxy. Seems like a good test quetion and I'd be happy for a clue?

Ron-Astro Pharmacist wrote:I'd be curious to know if those attempting degrees in astronomy have a class in celestial coordinates.

Celestial coordinates would amount to maybe a single lecture in a first year astronomy class. Astronomy majors would generally be expected to learn the mathematics of coordinate transformations and spherical trig, but it probably wouldn't be taught in an astronomy class. These things are part of the basic mathematical skills most physicists would pick up.

Ron-Astro Pharmacist wrote:And this is why I question how astronomy students are taught coordinate systems? I don't know where to begin to in order to visualize the triangle's true shape within the boundaries of our galaxy. Seems like a good test quetion and I'd be happy for a clue?

Celestial Coordinates (based on the Earth's axis of rotation) are great for figuring out where to point a telescope to observe a particular object.

But to begin to visualise things within the 3-D context of the Milky Way, Galactic Coordinates (based on the galaxy's axis of rotation, translated to the Sun) are more helpful.

Having a solid(ish) background in mathematics and analytical geometry, one of the first things I did when I started pursuing my interest in astronomy, was to gain an understanding of the transformations between Horizontal, Celestial and Galactic Coordinates. For the Solar System, there are also Ecliptic Coordinates, of which the useful origins are typically heliocentric, geocentric and tropocentric. I mainly used Wikipedia and its various online references as my guide. Knowing this stuff makes me enjoy astronomy a lot more.

Cherry blossoms
Night sky
Summer Triangle
Very nice....

My non traditional haiku ...

:---(===) *

Wonder if the Cherries are any good after 500 years???

:---[===] *

Boomer12k wrote:Wonder if the Cherries are any good after 500 years???

:---[===] *

I, too, wonder about that.

But the cherry tree is magnificent, whether its cherries are any good or not.

Ann

Craine wrote:

starsurfer wrote:I find this photo really soothing and enchanting! I really like seeing cherry blossom trees, they're so delightful! Seeing the Summer Triangle in the photo makes me think what a telescopic widefield mosaic of the constellation of Aquila with Ha by Rogelio Bernal Andreo look like? Within the boundaries of Aquila are many planetary nebulae (including NGC 6781 and NGC 6778), supernova remnants (a few are W51 and W44), lots of dark nebulae (LDN 673 is a particular favourite of mine) as well as the exotic binary system SS 433.

I think it would be nice to lie on the ground under the cherry blossom tree with my future soulmate and look up at the stars together.

I dunno. Somebody went a little overboard with the spiky fence there. They don't seem to want people near that tree.

That is your personal interpretation of the view. Problems can be surmounted with the correct amount of determination and perseverance, especially if it was about the happiness of my future soulmate (seriously where are you???!!!!).