May 21, 2019, the Laser Interferometer Gravitational-Wave Observatory (or LIGO) detected a signal that came from the merging of two black holes.
Wow! Where to begin. One of the world’s first gravitational wave detectors, LIGO, is a pair of laser interferometers located 3,000 km apart or about 1,800 miles. Locations are the Hanford Observatory in Washington and the Livingston Observatory in Louisiana. This detector is incredibly sensitive, detecting some of the weakest signals known to man. A short video summarizes the first observation made by LIGO told directly by the leading scientists in the endeavor. These scientists, Rainer Weiss, Kip Thorne, and Barry Barish, won the 2017 Nobel Prize in Physics for the discovery. LIGO is supported by the National Science Foundation (NSF), Caltech, and MIT.
We have come a long way with our understanding of the Universe and general relativity. Gravitational waves (GWs) are detected as disturbances in the interferometer. We can measure the duration and the frequency evolution of the signal and from that, we can apply general relativity theory to understand what took place and where for the GW event to occur. In 2015, LIGO reported the first ever detection of such an event, and it was determined to be from the merging of two black holes. These black holes merged to form an ever larger black hole.
Since then, LIGO and the twin observatory, VIRGO in Italy, have made several more observations of GW events! Isn’t that amazing? Most of the observations are consistent with general relativity (GR) modeling for binary black hole mergers with a single binary neutron star merge event, GW170814. All of these events are unique for different reasons but I will focus on the most recent detection yet, GW190521.
GW190521 is another binary black hole merge event, with the observed measurements being completely consistent with GR numerical simulations where they have assumed a quasi-circular compact binary coalescence – this is basically fancy talk describing two black holes slowly spiraling together in their respective circular orbits until collapsing and merging together. So, they were able to determine the most likely scenario to generate a GW signal with the same properties as GW190521 was a binary black hole system that ended with the two black holes merging together to form an altogether larger black hole.
First of all, this is amazing that this kind of research is possible. I just – wow. I mean, right? This is just incredible. The unimaginable has been imagined and then brought to life! Thank you, Albert Einstein. Second of all, this binary black hole (BBH from now on) merge event is special for two main reasons.
1) The two black holes that merged together have been measured to be 85 and 66 times the mass of the Sun, which we denote using M☉. The primary black hole (BH), the 85 M☉ one, is especially intriguing. The current understanding of stellar evolutionary theory for very massive stars predict that no black holes should be formed from stellar collapse between about 55 to 120 M☉. Of course, there are uncertainties surrounding where exactly this mass “gap” really lies but, the physics and modeling all appear to predict the same thing — no black hole remnants should be formed from stars between 55-120 M☉, give or take. But how much give or take? In the second report characterizing the astrophysical properties of GW190521, they report that the probability one of the black holes that merged together has a mass within the mass gap is 99%.
2) The mass of the final BH from the merge event is estimated to be ~150 M☉. This is the first strong evidence for the existence of an intermediate black hole. An intermediate black hole is a black hole that ranges in size from ~100s to ~100,000s the times the mass of the Sun. LIGO has detected several BH merge events, but only from stellar-mass black hole systems so far. GW190521 is the most massive BBH merge event observed to date!
The LIGO community announced the detection only just Sept. 2, 2020. Below is the GW detection signal from both LIGO detectors and VIRGO, and the signal represented in the time-frequency domain in the images displayed in the bottom panels. The signal was very short, with a duration of only 0.1 seconds and ranged in frequency from 30-80 Hz.
I believe it was first reported in Physical Review Letters here, of which the above image is adapted from. A really cool short video is shared below that nicely reiterates what I’ve just mentioned (and then some!).
Other cool materials are available here: https://www.ligo.org/detections/GW190521.php including a video of a numerical simulation of a binary coalescence that reproduces GW190521 (which I also display directly below because its COOL).
Above: Numerical simulation of two black holes that inspiral and merge, emitting gravitational waves. The black holes have large and nearly equal masses, with one only 3% more massive than the other. The simulated gravitational wave signal is consistent with the observation made by the LIGO and Virgo gravitational wave detectors on May 21st, 2019 (GW190521).
A New Frontier: Gravitational Wave Astronomy
Einstein predicted in general relativity theory that changes in the gravitational field will travel through the universe at the speed of light. These are gravitational waves and were only first confirmed in 2015. In 2020, we discover the most massive black hole merge event observed to date, and it happens to be pushing the limits of what we understand about the evolution of massive stars and, the nature and formation of intermediate sized black holes. Today, there are currently no confirmed intermediate black holes (IMBHs). There are several candidates, most of which reside in dwarf galaxies and are associated to low-luminous active Galactic centers. However, having no firmly identified IMBHs leaves many questions unanswered. How do IMBHs form? What conditions are necessary? The final BH responsible for GW190521 may give us clues and perhaps, future detections by LIGO and VIRGO may further reveal the Universe’s secrets.
I’ve been reading into this some and will discuss a short letter that investigates the origin of the primary 85 M☉ BH of GW190521 in the coming blog post!
This particular object I began looking more into right around the time I was also preparing for the written qualification exams at Clemson University. PHEW that is a stressful time to look back on. Maybe I’ll write more about the PhD process in the program in another blog post but, for now, let’s focus on the second Fermi object I investigated. I had a task to gather data for 12 newly detected very high energy sources – or VHE, which we will define at an energy E > 50 GeV which is among the highest energy for light, the gamma-ray range. The gamma-ray space telescope, Fermi, had just discovered these sources and were reported in 2016 (free and public pdf version available here). I was looking at multiple sources at once but, one particular source, led me somewhat down a rabbit hole and led to my second paper (in review but hopefully close to acceptance and publishing!) on the multi-wavelength analysis of the supernova remnant, G3447.1-0.1, which is found to be a likely origin for the newly discovered gamma-ray emission at the edge of the remnant. Does this sound familiar? It should! My first report was also on the discovery of gamma-ray emission on the edge of the Vela supernova remnant (SNR). Coincidence? Yes. Lol. Though this time the physics was a little more complicated but, all the more exciting!
First thing I noticed was this new gamma-ray source was pointing to the SNR G344.7-0.1, pictured below.
Admittedly my only experience so far with gamma-ray objects was the emission we identified as a shock-cloud interaction on the west edge of the Vela SNR and, so far, I was looking at another SNR with gamma-ray emission appearing on the west edge which overlapped with bright radio emission and a strong infrared filament. The bright radio emission can be seen in the left panel above. The green color is showing you where the radio emission brightens which is seen to be on the north and western regions. Similarly, we see brighten infrared emission in the northern-central and western regions as shown in the middle panel. Do you see the red filament in the middle panel? This coincides with the gamma-ray position and bright radio emission. Interesting.
By the way, the above images can be found in the following reports: (left) Eagle et al., 2020 (arXiv pdf version here), (middle) Combi et al., 2010 (arXiv pdf version here), and (right) available here.
So what does this mean, exactly? Well, in general, where one might see increased emission accompanying high energy emission, like this gamma-ray source, points to some kind of interaction that would accelerate these particles to radiate at the varying wavelengths. Each wavelength provides us different information about the particles responsible for the radiation and how they must be interacting with their environment. This also means we can infer what that environment is made up of.
Recall my first report we were able to determine the presence of a small neutral hydrogen cloud that was found to coincide precisely with the western wall of the Vela SNR that paired with the observed gamma-ray emission there. We can plausibly describe the gamma-ray emission as arising between the remnant’s forward shock – that is, it’s outer layer that was blast into the interstellar medium first at the time of explosion – is running into its surroundings and is colliding with and disturbing the material.
Let’s break down my first findings:
There is bright radio emission to the west of the SNR G344.7-0.1 as can be seen in the left panel above. This may suggest the remnant is interacting with its surroundings, much like the scenario just described.
There is a bright infrared filament that outlines the west wall of the remnant, overlapping with the bright radio emission seen and also coincides with the X-ray boundary of the SNR (we will see in the next post that the radio emission mostly follows the filled X-ray center appearance of the SNR).
The infrared emission suggests the remnant has recently swept up dust and shocked it that then radiated in the infrared regime.
At this point in time, I was leaning towards thinking it was another shock-cloud interaction. In my defense, the pieces seemed to be falling in a way that a shock-cloud interaction made sense but, also keeping in mind, it was my only exposure so far. I needed to keep an open mind.
I still had questions. If it were a shock-cloud interaction, then where is the cloud? Can I prove the presence of one? We knew at the time the SNR was in a dense environment in this part of the Galaxy based on its appearance across the light spectrum and by measurements of the surrounding densities but, the SNR’s distance was too uncertain to reliably pinpoint the existence of gas clouds in the same region of this remnant.
Furthermore, there is even higher energy gamma-ray emission found to the southwest of the remnant, in the TeV range! It was first detected by HESS, a system of Imaging Atmospheric Cherenkov gamma-ray telescopes that operate on the ground. HESS stands for the High Energy Stereoscopic System and more information on it can be found here. There were no other sources that were found to be in the same location as the HESS emission found at that time (which extends over a decent amount of space, it’s not just a point source). They labeled the HESS source as “dark” because they could not identify its origin due to the lack of information at other wavelengths. But now, we have a lead!
It was suspected before that the HESS TeV emission and gamma-ray emission from Fermi were coming from the same source. We plotted their flux data on the same plot and saw the data flowed well together, and could plausibly be from the same emission mechanism (above, left panel). The right panel shows the extent the HESS source has. It was unclear at the time what was unfolding here. If the TeV emission is connected to the supernova remnant, and the remnant is gamma-ray emitting on the western edge, how does it all fit together? What is going on?
Fours years ago I had just moved from Radford, Virginia to Clemson, South Carolina to begin my participation in the physics PhD program at Clemson University. I was devastated to leave Radford – I think I had developed a fairly strong bond to the town from my four years spent living and studying there. I think some of it was also being young and aware that Radford was the first “home away from home” for me and I was leaving it. And a sprinkle of the reality that is taking on bills and life on my own in a new way, even farther away from home. Home home. Out of state. Where I know no one. And am not familiar with any surrounding regions. And am really nervous of my ability to even participate in a PhD program of any kind. Yeah, so lots of feelings. Of course excitement was there, too. I’d experienced a big change before and loved every minute (going away to college) and I was fully aware of the opportunity that lie ahead of me at Clemson! With big life changes comes the usual fear of the unknown but so should being open to a new chapter of your life, one that could bring great things to you (but easier said than done amirite). What’s that saying? You know, ‘replace fear of the unknown with curiosity’?
The astronomy community, the LG (local group), at Clemson, spring 2018 (two years into the program). This photo makes me laugh because apparently I had told Ross (the one crouching) that he was blocking someone and apparently he was not.
I put a lot of pressure on myself that year. Entering graduate school is when I realized that I had anxiety issues and it was hitting the point where I could no longer ignore its impact on my life. I talk more about it here. When I entered Clemson, I began teaching introductory astronomy labs in conjunction with taking full time coursework. The Clemson physics and astronomy department does a placement test to help you figure out the proper track for your PhD program. I ranked the lowest score of my incoming class. They suggested to me that I take year zero, which would require two years of full time course work and re-visit courses that I was weak in (thermo, quantum, haha just kidding, all of them). I was the only one to enroll in year zero courses from my class and was the only graduate student among undergraduates for the entire first year of graduate school. I registered this as my first failure. I’m already falling behind, great. But, I was taking this seriously. I asked the department chair at the time, what are your success rates for students if they follow their recommended tracks? The students who do not succeed are almost always students who were recommended year zero and choose against it and failed trying to muscle through courses they couldn’t understand. Personally, I’d rather take six years to earn my PhD than just not earn my PhD at all. So, even though for whatever reason (ahem, imposter syndrome) I felt a little embarrassed being the only graduate student in my year zero classes, I signed up for them, and it turned out to be possibly the smartest decision I could’ve made at the time. (P.S. I’m pretty sure the only person to “look down on me” for being in year zero was myself and if it wasn’t, kindly fudge ’em.).
Of course I didn’t come to appreciate that decision until later. There were two new aspects to my life that, at first, made me very uncomfortable. Teaching to students my age Being the dumbest person in the class and be the only graduate student there.
I struggled with both that entire first year. I had a big teaching and course workload. My first semester in graduate school, I was teaching three 2-hour astronomy labs per week, grading, reporting grades, offering feedback, working with students, facilitating projects, grading paper reports. That’s just the teaching portion. Oh yeah and for astronomy labs we had to offer weekly observing nights as a final project. So we were out once to twice per week at night observing with the students, fall and spring semesters. On top of that, I was taking three courses: electromagnetism, classical mechanics, and quantum mechanics. There were all very hard and very time consuming, even as a year zero course.
It became obvious the first lecture that Clemson undergraduate degrees in physics were way more involved and intense than where I just came from. I was impressed and also terrified. This was mostly all new material for me but it wasn’t supposed to be. I was very aware of the holes in my education and this intensified my anxiety but it also intensified my determination. I didn’t prioritize social interactions my first year in Clemson and it was another added stressor to my life. It got lonely! But I was pretty busy studying physics, after all, I was catching up and was still quite a ways behind. And, ya know, teaching.
It was a lot having to balance all of these added areas to my life and it took some time to find the right balance. I kept my head down that first year of Clemson. I consider that a long phase where I was a little seedling waiting for the right time to sprout and bloom in growth! It was a very difficult year, and the second year at Clemson was not any easier. Graduate school really is no joke. Not to mention, there are a lot of problems that we still need to address in academia, too, so we can better support each other as we progress in our careers but, it’s equally valuable to be grateful for your experiences and your fervor to overcome the negative ones and how they have helped you grow into the scientist (or whoever you are!) that you are today. That is something to always be proud of.
While yes, it was exhausting and hard work, I changed a lot as a person (for the better, I think) during that short time and learned a lot about myself along the way. There’s so much more I wanted to mention with this first year of graduate school but admittedly I have been struggling with a bit of writer’s block and can’t find the right words. Nonetheless, I hope the bit I have shared can help someone pull through an awkward time of their life, one that maybe fosters similar emotions.
2020 Version (hopefully the last ever version of a blog post addressing surviving a global health crisis)
Hey guys! Long time no talk. We’ve all been experiencing a whirlwind of emotions, current events, and not-so-swift societal changes for a longer duration of time than one might prefer.
Since March 13th-ish, I’ve been working full-time remotely from home alongside (virtually) many of you. Though I am considered one of the lucky ones as my financial stability has not been compromised from the global health crisis. I hesitate to say we are in this together because the reality is that current events have impacted each individual in wildly different ways. While yes, we are all experiencing the global pandemic together, and trying to work together to protect each other and our families, the personal impacts and perspectives are broad to say the least. My deepest gratitude and best wishes are sent to you all during this time. Thank you for your sacrifice. Thank you for your kindness. Thank you for your thoughtfulness as we navigate a new world together.
Current events have stirred up a lot of uncomfortable feelings – anger, frustration, fear, and anxiety – to name the most unpleasant ones. I feel a change coming (but I don’t know if the outcome will be good or bad). To quote the world renowned author, an Indian political activist Arundhati Roy:
Another world is not only possible, she is on her way. On a quiet day, I can hear her breathing.
Unfortunately, I’m no psychologist or therapist. I don’t have the answers to the world’s problems but, I am managing to survive and have a few hobbies I have found to be a little therapeutic for me and would like to share, just in case anyone needs that extra boost to provide more meaning to their daily ritual while coping with a global pandemic. Let me stress these are things I’ve personally found to be enjoyable or helpful and may not be for everyone! Plus there is still a chance that these hobbies are just manifestations of a nervous breakdown like Ben Wyatt in the show Parks and Rec when he loses his job and invents Cones of Dunshire, an extremely involved nerdy board game (no offense) and also tries his hand at claymation movies and loses it when he realizes he spent like a month on 3 seconds worth of his movie.
Yoga of all kinds
1. I’d hate to be *that girl* but ummm, it really is a game changer and I encourage anyone to at least try it. I’m talking about yoga! I know – it feels like everyone suggests yoga for every ailment these days! But it really does help balance you mentally through self discipline and learning to tune into *what your body wants*. Yoga isn’t about being crazy flexible and balancing in weird positions. I mean it can be if that’s what you want but yoga practice is all about ~what feels good~. Everything else comes next.
I really enjoy the free YouTube videos Yoga with Adriene (and Benji!). I’ve linked her here. She offers hundreds of videos varying in length, difficulty, and theme. Her themes can be general like learning the basics to yoga or it can be more specific like hip and joint targeted practices, back pain, anxiety, even kids yoga! I like going to her playlists because she has them divided up by length. If I’m feeling like a shorter, deeper yoga practice, I peruse her 20-30 minute videos. If I want something more rigorous or perhaps more variety, I peruse the 30-45 minute playlist.
Plus side: she has a super cute doggo that is in almost every video and she has beautiful house plants, haha. I also personally find her to be a personable and relatable human being.
It’s easy to do at home and only requires your ~self~ and a yoga mat or blanket.
While we are here, the breathing practice that accompanies yoga I find to be very helpful in managing daily anxiety and stress. It slowly teaches you self discipline, focus, and attentiveness to your body and what it needs. It is a way to slow down and learn to shed the worries of everyday and just be. It is connected to meditation but this is something I still have not mastered and admittedly don’t practice too often.
2. I got a plant. Lol. It was a $3 grow kit at the front clearance section of Target. It was an Impatiens kit and came with everything but water to grow them. I got it right before everything started closing down and wanted to start growing it in my new office here but just a few weeks later, we were sent home. I decided to grow it at home even though my cats have killed pretty much every indoor plant I’ve ever had and any prior roommates’ plants (sorry about that).
I managed to perch the small pot directly onto the window latch, high enough where the cats couldn’t reach. It grew over the next month and then the next and it just looked like weeds. I transferred them over into a bigger pot and put little pieces of vegetable and fruit scrap in the soil to promote fertilization in time. They began to bloom about a month ago and I just transferred them over into another bigger pot and this time I added a food spike.
Maybe it sounds super lame but I’ve enjoyed taking care of the little plant, making sure it gets enough sunlight but not too much, watering it when it needs it, and encouraging growth and blooms. It’s been a delightful experience and I was so happy when I saw the little flower buds and their unique colors! I added a few friends with time. I can’t do anything too luxurious since I’m in a smaller apartment now but I have sunlight driven plants lining our front porch and that brings me enough joy for now.
Anyway, I know a lot of us have already invested time into plant care during quarantine so I know I’m not alone!
3. Whatever that means to you. It can be yoga, running, swimming, walking, biking, etc. I encourage avoiding gyms if you can for public health and safety (that includes protecting you! ️). Besides it’s so beautiful out! I like to bring my mask and have it around my neck and I choose routes that I know will not be heavy with pedestrian traffic. I wear the mask when I approach others. Some days if it’s cooler out, I can wear the mask for my entire exercise without any issues and I find that easier; it’s a little less to worry about running into someone without being prepared. I know this can be awkward to picture for some but, it truly is effective as we see up here in the northeast (and in contrast to what is happening in the south) and what we see over in Europe, China, and throughout Asia. Wear a mask if you can during your daily exercise if it’s outdoors and in public, for just a little while longer!
Stepping off my soap box now, I have enjoyed taking time to get to know my neighborhood by taking new routes in my runs and walks and recommend this to anyone really at any time, even without a pandemic. This could be especially important for anyone new in their area/region like me! In some ways I feel more connected to my community (especially because it has enabled me to meet neighbors!)
Maintain daily routine
4. Encourage a normal week schedule. Humans are creatures of habit and to an extent, we thrive in environments that have structure and purpose. Working remotely from home was a huge adjustment. At first it was kinda nice, felt convenient, easier. But then I started to abuse all of this time I was now spending at home. I started sleeping in all of the time, getting distracted by the pets or TV instead of working, cooking or cleaning instead of working, or calling family and talking about the pandemic instead of working (lol). And then I’d go through bouts where I would just work. Constantly. My work is all right there at my desk three feet away from where I sleep. It began to be all I thought about.
It cycled through like that. Lacking motivation and then either feeling behind or feeling energized and compensated by working a lot – sometimes at the sacrifice of physical activity. So I find encouraging an as-normal-as-possible daily routine can be crucial. I like to run in the mornings Monday through Thursday and begin work around 9:30am. Just having that one part of my schedule defined really helps layout the rest of what needs to be done. I’m also a big list person (as you’ll see here) which helps, too.
5. Find something you enjoy and find something that provides an outlet for you. This can be the same thing, if it so happens to be. For me, that is running. For you it could be reading or writing or cooking. This is up to you but it’s something I highly suggest checking in on regularly. “Have I been doing things I enjoy?” and “Have I been able to process this new life properly?“. Idk, the questions don’t have to be that philosophical, I’m just saying to check in with yourself every now and then and make sure you are dealing with new adjustments okay and if you’re not, consider what might help you do that and speak it aloud, maybe to someone that can help will it into existence with you.
Lastly, try to remember to shut off Netflix, shut off Tiktok, and spend time outside safely, maybe even sniff the crap out of your face covering so you can get a small whiff of those blossoming trees outside.
To love. To be loved. To never forget your own insignificance. To never get used to the unspeakable violence and the vulgar disparity of life around you. To seek joy in the saddest places. To pursue beauty to its lair. To never simplify what is complicated or complicate what is simple. To respect strength, never power. Above all, to watch. To try and understand. To never look away. And never, never to forget. — Arundhati Roy
This isn’t her first appearance in this blog either. Know her name: Dr. Jedidah Isler. I didn’t know this but we are from the same area. She was born in Virginia Beach, Virginia. I was born and raised in Hampton just across the bay. Dr. Isler earned her Bachelor’s degree in physics from Norfolk State University in Virginia, received her first Maser’s at
Fisk University in Tennessee, then her second Master’s at Yale, and later her PhD from Yale, just in 2014. She is well-known and renowned in the field for her research in blazars and quasars which are supermassive black holes powering an extremely strong jet of crazy energetic particles, radiating light that is detected here on Earth and then studied by experts like her. Dr. Isler had a fairly normal life growing up, in fact it seems she was somewhat similar to me! We both grew up adoring the stars but never really knew how to get into such a specific path. Though I’ll admit she sounds like she was a way better student than I was. She genuinely was always curious and pursued valuable interests and opportunities but not without ever noticing she was the only black woman there. Because of this, Dr. Isler fought more obstacles to get to this point today,
After earning her PhD from Yale in 2014, as the first African American woman to do so in physics, she went on to be a National Science Foundation Astrophysics Postdoctoral Fellow for 3 years at Vanderbilt University while she continued her research. Today – as in right now – she works at Dartmouth College as an assistant professor of astrophysics! She is not a trailblazer yet. She is currently trailblazing – at this very moment (*ALSO she is hiring!)! I’d like to honor her strength, courage, and hard work by including her as not only an amazing female astrophysicist you should know but also as the first amazing female astrophysicist you should know.
Dr. Fabiola Gianotti is currently the director-general of CERN – The European Organization for Nuclear Research – based in Switzerland. The CERN facility is mainly to study particle accelerations and mechanisms with particle accelerators like the Large Hadron Collider (LHC). The CERN facility is appropriately famous for several ground breaking discoveries since beginning operation including the famous 2012 discovery of the long-sought Higgs boson particle.
CERN is seriously a display of amazing capabilities. The LHC is the world’s most powerful particle accelerator and is made of MILES long construction of magnets. It’s a big deal. And Dr. Gianotti is a big deal because she’s in charge of it. Not only that, but she is the first female to do so. She is currently serving her second term of office as the director-general. Dr. Gianotti received her PhD in experimental particle physics from the University of Milan in Italy in 1989. She has authored and co-authored over 500 publications in peer-reviewed scientific journals and has been awarded several very prestigious awards including the Medal of Honor of the Niels Bohr Institute of Copenhagen in 2013. As a woman pursuing a career in a male-dominated field, it was no easy thing to push through barriers to get to where she is today. Today, Dr. Gianotti aims to provide ample support for her colleagues, both male and female, who have children. Many women in physics struggle to maintain a successful balance between a rewarding career in physics and having a family and sometimes feel forced to choose between the two. Dr. Gianotti speaks from some personal experience and women who work in this field can surely relate (I can). Hats off to Dr. Gianotti, helping the workplace become women-friendlier!
Dr. Jocelyn Bell Burnell is, like, a personal hero of mine. Well, all of these women are but I have a soft spot for Jocelyn because we both got wowza’d by the same thing – pulsars. Dr. Burnell, however, was the first one ever to be wowza’d by pulsars. She was even a part of naming the darn things!
In 1967, Dr. Burnell was a PhD student at University of Cambridge in the UK when she noticed a “bit of scruff” on her chart recorder while investigating the radio sky. She was taken aback by this detection and half heartedly pursued confirming the detection, thinking it was probably nothing. Suffering from imposter syndrome, she would surely believe she made a silly error before believing she just discovered a new astrophysical object. Her graduate supervisor would end up partially believing the blip, which turned out to be extremely regular in its repetition and behavior, to be extraterrestrial intelligence. So much so, he coined the object “LGM” for little green men. Later, it was understood to be an astrophysical object and today, known as a pulsar. A furiously rotating neutron star, spewing beams of light towards Earth, like a light house; A beacon of light that you can count on seeing in a predictable way.
Dr. Burnell today is very well known for this discovery and for some small controversies around the Nobel Prize in Physics in 1974 going to her graduate supervisor for the discovery of pulsars. Although, Dr. Burnell seems to hold no resentment about it. I’ve had the opportunity to speak with Dr. Burnell and she is quite a fascinating woman who now advocates loudly for women and women with children in our field. She is a big, outspoken victim of imposter syndrome (which, for other victims, like me, greatly appreciate her bravery and wisdom). She is not only the discoverer of the beacon of light from pulsars but also is a beacon of hope for all women in the physics field.
Nancy was a pioneer right around the same time Katherine Johnson was pioneering for black women at NASA. In the mid-1900s, NASA was not a workplace for women. Women were discouraged from studying math and science, Nancy being no exception.
Nancy recalls her mother showing her constellations in the night sky, grabbing her attention. She decided very young that becoming an astronomer was the path for her. In 1949, Dr. Roman earned her PhD from the University of Chicago. In 1959, she began work at NASA, where she became the first chief of astronomy in the Office of Space Science. She was also the first woman to hold an executive position at the space agency. Dr. Roman was called the mother of Hubble, the optical space telescope that was launched in 1990 and is still operating today, 30 years later. She was a program scientist who was basically the person who would convince people the mission was worth doing, as she puts it. Dr. Roman had a lot to do with how the telescope was designed and built and kept up appeal and interest from investors.
On May 20, 2020, NASA announced it will name the next-generation space telescope after Dr. Roman. The Wide Field Infrared Survey Telescope (WFIRST) is currently under development and is set to launch in the mid-2020s. The new name of the telescope is now The Nancy Grace Roman Space Telescope. It will investigate open questions in astrophysics and cosmology such as the force behind the universe’s expansion and to search for distant planets beyond our solar system. NASA rejoices Dr. Roman’s efforts, describing her as ‘tirelessly advocating for new tools that would allow scientists to study the broader universe from space’. This is also in memory of Dr. Roman, who passed away in 2018 at the age of 93.
Cecilia is one of the women known as the Harvard Computers, which consisted of a number of women working as skilled astronomers, collecting and processing optical data at the Harvard Observatory in the late-1800s onwards. Cecilia was among Williamina Fleming, Annie Jump Cannon, and Henrietta Leavitt and others, who tirelessly studied light from stars. Studying stellar spectra, the Harvard computers made several major contributions to astronomy, including the famous stellar
classification system – Oh, Be A Fine Girl, Kiss Me! or OBAFGKM, which types the varying stars based on their optical spectra. Cecilia, in particular, made a pretty big discovery herself, which she and her PhD thesis advisor squabbled over for years. Henry Norris Russell was one of the astronomers who developed the Hertzsprung-Russell Diagram, a fundamental graph displaying stellar evolution still used widely today. Russell was sure Cecelia’s work must be wrong.
In 1925, Cecelia submitted her PhD thesis, which was comprised of extensive analysis of a huge dataset of stellar spectra, all showing enormous abundances of hydrogen and helium, a surprising result at the time. Today, it is understood that hydrogen and helium are the most abundant elements in the universe. In the Milky Way alone, it is estimated the baryonic mass is roughly 74% hydrogen, 24% helium, and all else being remaining heavier elements. In 1925, however, it was still thought that stars were made up of similar composition as the planets, like Earth. There was no reason to believe otherwise until, alas, abundant evidence shows us that indeed, the universe is made up of mostly the two lightest elements. Her discovery profoundly changed our outlook on the universe, stellar evolution, cosmology, and more. By 1956, Cecelia had accomplished becoming the first female professor at Harvard and the first woman to become department chair. She passed away in Cambridge, Massachusetts in 1979.
So technically, Jeanette was a mathematician but I’ve included her as an astrophysicist because she is well-known for her contributions to knowledge on the Sun’s sunspot cycle. Jeanette was the first African-American mathematician to be employed at the NASA’s Marshall Space Flight Center, based in Huntsville, Alabama in 1964. Jeanette grew up in Alabama when segregation and other racial discriminatory laws and behaviors were normalized.
She went to an all-black school and graduated from high school in 1956. She went on to receive her Bachelor’s and Master’s from Alabama A&M University. Her 1967 report, Survey of Solar Cycle Prediction Models, provided new methods for improving predictions of the solar sunspot cycle. She went back to school some time later to earn her PhD in computer science and went to work at the Goddard Space Flight Center in Maryland. She worked as a computer systems analyst responsible for analyzing and directing NASA systems. During her career, she remained passionate about inclusion and equity. She volunteered as an equal employment opportunity officer in her spare time. Jeanette retired in 2005 and in 2017, NASA honored Jeanette for her skill, perseverance, and positive attitude as part of the first Alabama Historically Black Colleges and Universities Roundtable Discussion.
Six extraordinary women of science and their stories
We acknowledge these women fought various obstacles in the workplace from historical and systematic oppression of their gender and for some, they were discriminated against for their race as well. We applaud these women for their courage, knowledge, and wit that it took for them to accomplish their goals in spite of added difficulty.