ring around the rosies

by Ted Frimet

carmen sandiego ?

A few months ago, AAAP Program Chair, Ira Polans, invited Dr. James Lowenthal of Smith College to lecture our club on a Tuesday night, in Princeton. Dr. Lowenthal wooed us with his Hubble Space Telescope (HST) time, and his nascent discovery of multiple gravitational lensing events. I am especially indebted to Dr. Lowenthal for taking the time, and for extending an invitation to peruse his name, on open source images. All of which can be found as a MAST data retrieval request from, the archival hot seat at STSCI.

If you go back a few issues, and re-visit Fiddle-Dee-Dee (https://princetonastronomy.wordpress.com/2018/05/01/fiddle-dee-dee/)
you will find our first attempt to colorize HST images.

Now that time permits, post lecture of course, we visit, however contritely, three images produced by the progeny of of Dr. Lowenthal’s space telescope time.

Below is a reprint of HST Proposal 8191, obtained from
last visited on July 7, 2018

We propose deep WFPC2 imaging and STIS slitless spectroscopy of two of our ultra-deep VLA fields. Those 4- and 6-cm maps have 1-Sigma levels of 3 and 11 Mu-Jy, respectively, comparable to VLA observations of the HDF, and show 14 and 9 sources in statistically complete samples. Keck spectroscopy and imaging to B, R, I ~26.5 have identified most of the sources as compact, luminous starbursting and interacting galaxies at redshifts z es1; about 25 at z>1.5. Our goals here are: {1} identify the remaining sources; {2} pinpoint regions of star formation; {3} quantify the incidence of interaction using spatially-resolved kinematics; {4} quantify morphologies; and {5} constrain the evolution of these faintest of radio sources. Only the HDF and one other field have such deep VLA, HST, and Keck data, and there is strong evidence that field-to-field variations are significant. WFPC2 images with F814 will provide the resolution needed to measure morphologies on sub-kpc scales, identify interaction- induced star-formation, and distinguish AGN from non-AGN components. Slitless spectroscopy with STIS will reveal faint emission-line sources invisible in our Keck images and will provide spatially-resolved kinematics, necessary to disentangle the star forming components in interacting systems. The VLA fields extend over some 8 min each, so both WFPC2 and STIS can be used simultaneously.

Giddy with the tedious nature of the above abstract proposal, we ventured forth, with the good doctor’s permission, to colorize some, if not all of his open source material. It is in the spirit of this good old graphic digital designers intent; an attempt to highlight what may not have been visible in the plain, and very ordinary black and white deep field HST images, for our lecturers intended purpose.

Clearly, what you are about to view are not the many-color girded view of HST deep space photographs. It is, however, the result of combining three very well related images that represent the gravitational lensing effects that Dr. Lowenthal was studying. It is noteworthy and memorially correct to note, here, that Dr. Lowenthal discovered more gravitational lensing effects, than any other well placed study, in recent memory. I could further enhance the image to produce a self-evident Einstein Ring. However, that would be as mischievous as the HST graphic artist painting an UV emitting White Dwarf, well, white!

So, without further adieu, here is my first, and probably last attempt at false-coloring Hubble Deep Space, highly luminous, and strongly lensed sub-millimeter galaxies. All source images used are public release in the Mikowsky archives, with study done by Dr. James Lowenthal.

red channel:
RA (J2000) 08 44 44.043
Dec (J2000) +44 31 58.56
start time 2001-01-25 14:58:28
end time 2001-01-25 15:05:52
exposure time 400.000

green channel:
08 44 43.981
+44 31 59.91
2001-01-22 11:24:44
2001-01-22 11:32:08

blue channel:
08 44 44.149
+44 32 00.79
2001-01-27 10:24:56
2001-01-27 10:32:20

Each frame was “centered-on” in Photoshop, and a minor curve was applied

Further credit to:

Papers related to proposal id:
The morphology of nine radio-selected faint galaxies from deep Hubble Space Telescope imaging — Roche, Nathan D. et al 2002MNRAS.337..840R

Here are the three “untouched” images:

And here is our composite graphic:

This entry was posted in Mid Summer 2018, Sidereal Times and tagged . Bookmark the permalink.

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