People_of_Space: Laurence Profile picture
@ET_Exists is a USAF Veteran, Mars Geologist, 10-Year Recovering Alcoholic, Practicing Catholic, and Self-Published Author.
18 Oct
About my book, “Outer Solar System Moons: Your Personal 3D Journey” (Printed and digital copies can be purchased at

I got the itch to author this after the success of my colleague’s book, “Mars: Your Personal 3D Journey” by @AntonioParis! 1/n
All of the 3D images were made in @Photoshop and the final draft was made in @powerpoint. While the entire process was very arduous and frustrating at times, the result has been nothing short of rewarding, as the book is finally starting to sell bigly! The very positive...2/n I’ve received has made the journey worth it, so far, and I hope to author another book again, someday. I’m extremely grateful to Dr. Jessica Noviello for her amazing Introduction and feedback prior to publishing, and the quote from @AstroDocScott in the...3/n
Read 4 tweets
18 Oct
About Me (@ET_Exists)...

I grew up in the San Francisco Bay Area and after wasting time post-high school trying to figure out what I wanted to major in, I enlisted in the @usairforce where I served six years as an Aircraft Mechanic. I had a childhood fascination with...1/n, so I opted to major in Astrobiology @FloridaTech. I struggled academically, but conducted two years of successful exoplanet research with Dr. Darin Ragozzine, and decided to transfer to @SESEASU to be closer to home and since it was a clean transfer I was able to...2/n
...graduate the exact same time I would have had I stayed @FloridaTech (May ‘17). I had switched to geology because I wanted to study something I could see and didn’t see myself writing code the rest of my career and enrolled as a Non-Degree Grad Student studying Europa w/...3/n
Read 8 tweets
15 Oct
Next year the biggest astronomical event visible from the UK will be a Partial Solar Eclipse on 10 June 2021. Some parts of the world will see an Annular Eclipse. I've got plans to capture the Partial one from here.
This will, weather permitting, be only my second go capturing a Solar Eclipse. My first time was back in March 2015. I had my Sky-Watcher Telescope, Canon 1200D camera and Nikon L810 camera for pictures. This is one of the pictures I took. Image
Next year's eclipse will only be about a third obscured from here and the rest of the UK. Nevertheless I'm planning to use my Sky-Watcher again, and Celestron telescope to capture the big event. This is the smiley face view I hope to see. Image
Read 8 tweets
15 Oct
After the Geminids meteor shower the next big Astronomical event is a Solar Eclipse on 14 December. However not visible from the UK. Handily there is a big Astronomical occurring after that, visible all over the world. A super conjunction on 21 December. Jupiter and Saturn.
Jupiter and Saturn will appear so close together they will nearly look like one object. Should be an amazing sight in Binoculars and telescopes. Also a great photo opportunity. Will be tricky to observe and capture from the UK though.
The planets will be very low on the horizon from my location and mid northern latitudes. Won't be possible for me to see them from my house so I'll have to take all my doings to another spot. I'll need a clear southern horizon looking to the southwest. I know the perfect spot.
Read 12 tweets
7 Oct
Good morning! My week on People of Space is dedicated to the theme of women in space and STEM. We've looked at the @UNOOSA #Space4Women programme, and space books by women, with forays into the works of Margaret Cavendish (1600s) and Barbara Ward (1970s).
And what a week it's been! Women are pretty thin on the ground in NobelPrizeLand, but first of all was the good news that Andrea Ghez was awarded a Nobel Prize for Physics for her work on black holes (with Reinhard Genzel)… #WomeninSTEM
Then the Nobel Prize for Chemistry was won by Emmanuelle Charpentier and Jennifer A. Doudna "for the development of a method for genome editing."… #WomenInSTEM
Read 20 tweets
7 Oct
Ready for some World Space Week cuisine? #WSW2020
First of all, the Russian dressing!
1/2 cup mayonnaise
1/3 cup ketchup
1 tablespoon white wine vinegar
1 tablespoon onion finely minced
1/8 teaspoon salt
1/8 teaspoon pepper
Read 13 tweets
5 Oct
Good morning everyone! I've just been in an amazing panel about satellites and #Space4Women - I'll post the link to the video here or over at my regular account when it's up. #WSW2020
Today is pretty flat out - later on I'll be chairing a session at the Australasian Space Health Symposium as well as presenting a paper. Is the paper finished? What an interesting question which I will decline to answer at this time. #WSW2020
You can find more details about the Australasian Space Health Symposium here. I'm pretty sure it's not too late to register (it's free)… #WSW2020
Read 4 tweets
5 Oct
A quick round-up of more space books by women! The Secret Life of Stars by @lisaharveysmith #Space4Women #WSW2020
Read 5 tweets
5 Oct
Time for my third book in this series on space books by women: Spaceship Earth (1966), by Barbara Ward, Baroness Jackson of Lodsworth - a pioneer in the philosophy of sustainability and social justice #Space4Women #WSW2020
The concept of 'Spaceship Earth' is usually associated with Buckminster Fuller and his 'Operating Manual for Spaceship Earth' (1969) - but Barbara Ward published her book 'Spaceship Earth' in 1966. #Space4Women #WSW2020
The origins of 'Spaceship Earth', however, actually pre-date the Space Age! In 1879, the US economist Henry George wrote: 'It is a well-provisioned ship, this on which we sail through space'. More history here:… #WSW2020
Read 13 tweets
22 Sep
So let's see what a Pulsar looks like from the surface to the interior
The outer crust of Pulsars is made of nuclei (like iron) in a sea of electrons. As we go deeper inside, the nuclei are more rich in neutrons (like exotic nuclei in our labs)
As we enter deeper into the Pulsar, extreme densities start to distort the nuclei, twisting them into strange shapes, resembling "pasta" 🍝 (yes, you read that right) 😉
Read 7 tweets
22 Sep
Pulsars are effectively laboratories in Space that allow us to probe the behaviour of dense matter & its fundamental constituents
But what about laboratories? Nuclear experiments? Particle accelerators? The most powerful heavy ion colliders we can build on Earth? Why do we need to study Pulsars so far away in Space?
Nuclear experiments probe matter at the density of a nucleus of an atom. But what is the nature of nuclear interactions at 10x nuclear density? Known stable nuclei have same number of neutrons/protons. But Pulsars ("Neutron Stars") have many more neutrons than protons!
Read 5 tweets
22 Sep
Astrophysical data indicates that Pulsars weigh 1-2 times the Sun, within a diameter the size of a city (~10 km). What does that say about its interior? Watch this clip to find out 👇
A simple "back of the envelope" calculation (Density~ Mass/Radius^3) tells us that pulsars are the densest objects in the Universe! 😱 That their densities go beyond 10x nuclear densities here on Earth
Data also shows that Pulsars are "ultracold" (yes, you read it right) compared to the energies of its component particles (even superfluids could appear in its core!)
Read 5 tweets
22 Sep
From the multiwavelength astrophysical observations of Pulsars, information about its global structure (Mass or Radius) can be obtained
If pulsars are in binary with another pulsar, or another compact object, they show effects due to its strong gravity beyond simple Kepler's laws
From these effects, masses of pulsars in binary can be determined very accurately
Read 8 tweets
21 Sep
So let us look at some #space and ground-based telescopes that give us information about #pulsars via #multiwavelengthastronomy
Most gamma rays coming from space are absorbed by the Earth's atmosphere, so the telescopes are space based. The @fermitelescope & Integral missions have discovered many gamma-ray pulsars
In addition to the X-ray telescopes such as @chandraxray & @NASANuSTAR, the recently launched #NICER mission will help us probe the pulsar interior (I will explain this tomorrow)
Read 6 tweets
21 Sep
To understand what the compact object in the centre of the nebula is, we have to go back in time. The story began with this young graduate student at Cambridge, Jocelyn Bell
In 1967, she noticed a strange “bit of scruff” in the data from the radio telescope she had built for her project, designed by her thesis supervisor Anthony Hewish, to study quasars
The signal, extremely periodic in nature, wasn't from a quasar, and after a careful investigation she could rule out manmade sources.
Read 5 tweets
21 Sep
As soon as we are out of city limits, we see this amazing night sky full of #stars 🤩 [Photo from Brahmatal trek (3734m), Indian Himalayas, Jan 2019]
What we see above is our Milky Way galaxy, filled with approx 100-400 billions of stars 😮 ✨
But there is so much more than meets the eye! The stars we see comprise only a tiny fraction of the entire electromagnetic spectrum
Read 4 tweets
20 Sep
So ten years ago, when I was awarded the prestigious Alexander von Humboldt @AvHStiftung for postdoctoral research in Germany, I jumped at the chance 😉 #themissuniversemoment 😂
I spent a couple of amazing years doing research at @UniHeidelberg, a German Excellence University and also its oldest 🤓🏰 ImageImageImage
My workplace was the Institut für Theoretische Physik on 16, Philosophenweg (Philosopher's walk) (private house of Nobel prize winning nuclear physicist Hans Jensen) with a breathtaking view of the Altstadt (old town) 😍 ImageImage
Read 5 tweets
20 Sep
Today is Sunday, so we won't talk about work.. instead let me tell you some stories from my academic journey 😀 Image
I obtained my doctoral degree in Astrophysics from the reputed Saha Institute of Nuclear Physics in Kolkata, India in 2009. I was also awarded a medal for outstanding performance during my #PhD 🤓 ImageImage
During this time, I worked in long-term collaboration with @goetheuni in Frankfurt am Main, Germany and also won @DAAD_Germany funding for doctoral research ImageImage
Read 4 tweets
19 Sep
Favourite sci-fi books. Add yours here!
This imaginative planetary adventure from 1951 from Robert Heinlein "Between Planets" Image
Hard to pick just one Arthur C. Clarke book, but going with "Childhood's End" Image
Read 5 tweets
17 Sep
Today I want to share a few cool space resources that I've stumbled across. A thread.
@stuffinspace Stuff in Space is a realtime 3D map of objects in Earth orbit, visualised using WebGL and updated daily!
@poliastro_py is an open source Python package dedicated to Astrodynamics and Orbital Mechanics.…
Read 11 tweets
15 Sep
Optical Systems Engineering!!! What is it? Why do we do it? How do we do it? I’ll try explaining in just a few tweets. Image
For context we’re talking optical imaging cameras for satellites for earth observation, but the same ideas and processes are relevant for astronomical telescopes and other forms of payload or ground based equipment. Image
Like a traditional spacecraft-level system engineer, the Optical System Engineer is responsible for the whole optical system -> requirements, design, analysis, manufacture, assembly, verification and even sometimes in-orbit operation. Image
Read 10 tweets