Thursday, July 09, 2015

Blobs in Space!

Interesting times, but not much time to comment on them.

The Sun is doing it's thing as always. Not much too special to talk about today. For more data go to

 AIA 211 Angstrom band is red, AIA 193 Angstrom band is green, and AIA 171 is blue

In our back yard the robotic missions to Minor Planets Ceres and Pluto are really getting interesting.

Dwarf planet Ceres as seen by NASA's DAWN mission
NASA's DAWN mission to Ceres is continuing its second mapping orbit. The CERES Image Of The Day website is worth looking at every now and again. The image on the right was taken on  Feb. 19, 2015 from a distance of nearly 29,000 miles (46,000 kilometers) from Ceres.

Fun Ceres facts: It is about 590 miles across, and accounts for about 25% of the entire asteroid belt's mass. Yet it is less than 1/14th of the mass of Plute, the other dwarf planet of note at the moment.

It is amazing to finally see non-deconvolved images of Pluto that actually look like something other than a blurry blob. [Read more at] Original images from JHU Applied Physics Lab.
New Horizon's image of Pluto and Charon taken on 06/29/2015 at a distance of 18 million km.

Sharpless 308. Copyright Kfir Simon
Bubbles. About 5,000 light years away from us is the beautiful Wolf-Rayet (stellar) bubble Sharpless 308. It is about 60 light years in diameter, and only 70,000 years old. The genetically modern human ancestors of ~98% or more of your DNA were present and still hanging out in Africa, but some were about to set off on extended holiday. [Credit: Kfir Simon, as seen on APOD]

Speaking of Wolf Rayet stars, how about Wolf Rayet galaxies? Why, it's a Hubble image of the famous SBS1415+437. (Just kidding, this galaxy is not well known, even among the so-called Wolf Rayet galaxies.)
The Wolf-Rayet galaxy SBS1415+437. Credit NASA/HST/Aloisi et al?

Go read the background at's Image of the Week. Although it is not clear from the Image of the Week site the image is probably that described in Aloisi et al, 2005, ApJ, 631, L45 which detected the presence of old (1+ Gyr) stars in SBS1415+437., which had bearing on an old (by now) debate about whether the so-called Wolf Rayet galaxies in the local Universe where young galaxies just experiencing their first burst of star formation (Answer: In general no, they're not).

I of course chose the bubble, superbubble, Wolf Rayet galaxy, and NGC 6503 images because I did some work on wind-blown bubbles, superbubbles, WR galaxies and NGC 6503 back in the days I was a professional astronomer. Red and green Solar images are for Micah and Caelan, who are very into that type of solar imagery at the moment.

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