Akarsh Simha


Picture of Akarsh with his 28-inch f/4 telescope taken at the 2024 Golden State Star PartyPosing with my 28-inch telescope at Golden State Star Party 2024

Sketch of the Whirlpool Galaxy made at the eyepiece of Akarsh's 18 inch telescope over the span of 2 hours under the excellent skies of Massacre RimSketch of the Whirlpool Galaxy made at the eyepiece of my 18-inch telescope

Brief bio

I am in my 30s and presently live in the San Francisco Bay Area in California. I have experience as a theoretical and experimental physicist with skills in optics, applied mathematics and fluid dynamics, and as a software engineer with skills in machine learning, compilers and software frameworks. Even though I did not formally study computer science/engineering save for a few classes, it has been a passion of mine since high school. Association with peers studying computer science during undergraduate college, the Google Summer of Code program, as well as working on the open source project KStars for many years honed my skill with computers before I started my career as a software engineer.

I got a PhD in Physics from the University of Texas at Austin. I was advised by Phil Morrison and co-advised by Mark Raizen. My thesis was on theoretical and experimental aspects of Brownian Motion in Liquids. I was very fortunate to work both on theoretical and experimental aspects of the same problem, picking up a diverse set of skills in the process. My publications are listed on Google Scholar.

I then worked at Apple, Inc. in several different aspects of machine learning – a training framework (thought of as a compiler), training/evaluating/deploying several neural-network models on the iPhone and Mac, building model-in-the-loop data annotation tools, contributing to model-training infrastructure, defining and supervising the delivery of complex training data for novel models, and on a model-deployment framework. In addition, I had an opportunity to rotate for 3 months into an LLVM-based GPU compiler team contributing to performance optimizations. One of the features that I am proud of contributing to was the static subject lifting feature on iOS released in 2022 that can be used to make stickers, that was highlighted in Apple's WWDC keynote as well as in an Apple machine learning blog post.

In my personal time, I have fun doing astronomy as a hobby, tinker around with Linux machines, learn math and astrophysics, go hiking / car camping / road tripping / photographing, build small DIY things, write code (especially for KStars), and work out.

Professional Background

My resume is available here, updated May 2024.

Amateur Astronomy and selected personal projects

My curiosity with the night sky began in a set of books with pretty pictures I came across in 9th grade, and I always wondered if I could some day see some of those cool-looking nebulae and galaxies. Around the same time, I found KStars as part of my Linux install. Trying to install every distro of Linux shipped with the "Linux For You" magazine was a pastime in high school. Eventually I found out that I could go to the Association of Bangalore Amateur Astronomers and build my own telescope!

That kicked it off. Once I built my 8-inch f/8 telescope, I was hooked to visual observing, i.e. putting my eyes at the eyepiece and looking at objects. I have tried my hand at astrophotography and figured that I get enough technical problem-solving at work and in my other hobbies to have another hobby of that sort. I also find observing with my own eyes much more personal -- the idea that photons from a galaxy a billion light years away traveled through space to impinge on my retina delights me. My primary passion within visual observing is to look at things beyond the solar system, especially galaxies.

I primarily use a 28" f/4 telescope and an 18" f/4.5 telescope. The latter is on a Gregg Blandin equatorial platform. Typically, I don't like to bind myself to a specific observing list and like to pick objects that interest me from various sources including the Deep Sky Forum, Adventures in Deep Space and Larry Mitchell's TSP lists. I have a somewhat outdated listing of the 1000+ deep-sky objects I have logged notes on over here

A long while ago, I created a pipeline to auto-generate observation logbooks for deep-sky observing using KStars and LaTeX. The code isn't particularly clean or something I'm proud of, but I am definitely pleased with the results. Here is a link to The Logbook Project. The code is on my Github.

One of my recent projects has involved adapting plate solving to visual hobby astronomy, by attaching a camera to my finder scope. Ever since I developed this system, I have stopped star-hopping. The system uses a combination of open-source plate-solving software and a custom personal software stack integrating an Arduino-based 9-axis IMU to provide a way to turn my telescope into a push-to system. Details can be found here. The part I'm most proud of is the cool math that went into building this system -- the IMU recalibration algorithm is based on quaternions and I remember the moment when I finally fixed a sign mistake in several pages of algebra and the system started working as expected! The source code for this project can be found here.

Over the years, I have developed a DSS Query web tool, which is designed for amateur astronomers' needs: it resolves object names using SIMBAD, fetches images of the sky from various services, and allows you to adjust rotation to match your eyepiece view. Also can click on a position in the image and it will query SIMBAD to find the designation nearest to the cursor. It also makes querying other surveys like PanSTARRS, Hubble Legacy Archive etc. easier. It also makes annotating a DSS image with labels easy, so you can share it on forums etc. JavaScript and web programming isn't exactly my forte, so this was mostly built to scratch an itch.

I have also compiled a List of Peculiar Galaxies that I observed which showed interesting structure at the eyepiece of my 18" telescope.

I reverse-engineered the binary format used to store the Mitchell Anonymous Catalog in the no-longer-sold MegaStar5 planetarium software, and released it with Larry Mitchell's permission and support here. This is a catalog of galaxies created by Larry Mitchell through a laborious manual examination of the POSS plates, at a time when these galaxies were uncataloged and did not have LEDA / PGC designations. Larry's monumental work was only available through the MegaStar5 software prior to this effort.

Astronomy Talks

Publications

My professional publications are also available on Google Scholar.

Experiments on Brownian Motion

Theory (Low Reynolds-number fluid dynamics)

Other physics

Amateur Astronomy

Some links of interest


You may contact me at akarsh at kde dot org