What is the mysterious red rectangle around HD 44179?

[Dotini]

How charming!

(Photo: ESA/Hubble and NASA)

http://www.usatoday.com/story/tech/sciencefair/2016/04/08/star-red-rectangle-nasa-hubble/82796522/

 

[jfizzix]

If I had to guess, I would say at least some of the "rectangularity" in the image is likely due to the shape of the aperture on the telescope looking at it. Rectangular irises make rectangular streaks, and hexagonal irises make hexagonal streaks. The nebula is definitely more rectangular than what could be explained by aperture effects, which is pretty darn cool.

See for example this Hubble photo of Sirius

(Source: http://hubblesite.org/newscenter/archive/releases/2005/36/image/a/format/large_web/)

Here, the star is round, but there are well-defined streaks at 90 degree angles. These streaks are purely due to aperture effects.

Pretty, though :)

 

[Drakkith]

I don't think i has anything to do with the aperture shape. From the photo's source:

The reason for its rectangular appearance is because we're seeing the nebula from an unusual angle. The star is likely shooting out cone-shaped gas clouds, which to us seem to form a rectangle, NASA said.

Besides, most telescopes have round apertures. I don't think I've ever seen one without a round aperture.

Here, the star is round, but there are well-defined streaks at 90 degree angles. These streaks are purely due to aperture effects.

Those spikes are diffraction spikes, which have little to do with the shape of the aperture as far as I know.

 

[jfizzix]

Those spikes are diffraction spikes, which have little to do with the shape of the aperture as far as I know.

Those spikes wouldn't be at 90 degree angles unless the light was passing though a rectangular aperture/iris.

 

[Drakkith]

Those spikes wouldn't be at 90 degree angles unless the light was passing though a rectangular aperture/iris.

Sure they will. Take a look at the following picture.

The aperture with four spider vanes has cross-shaped diffraction spikes.

Source: https://en.wikipedia.org/wiki/Diffraction_spike

 

[jfizzix]

I stand corrected.

 

[rootone]

I don't think anything was wrong with apparatus, nature just does interesting things which are not predictable.
Nobody expected a hexagon formation on the north pole of Saturn, but there it is.

 

[Dotini]

I don't think anything was wrong with apparatus, nature just does interesting things which are not predictable.
Nobody expected a hexagon formation on the north pole of Saturn, but there it is.

Yes, this is how I think about it, too. I certainly wouldn't rush to bet the farm on the first explanation offered by a journalist. For me, the endless beauty, variety and novelty of the universe is enough to make me feel loved, charmed and amused.

 

[Dotini]

- "Strange activity at the molecular level"

- A red glow, "Extended Red Emission (conveniently ERE for short) has been known but inexplicable for more than 30 years".

- "Unusual clusters of PAHs that are charged and highly reactive but, at the same time, have a stable, closed-shell electron configuration"

These are the explanation now on offer by writers at space.com.

http://www.space.com/3658-mystery-red-space-glow-solved.html
http://www.space.com/32655-mysterious-red-rectangle-hubble-telescope-sharpest-image.html