Life and work of Pakistani astrophysicist at NASA
Since I was a child, I have been fascinated by the alluring night sky, the glittering moon and countless stars over the horizon. All throughout my childhood, space sciences and astronomy remained my passion.
While researching personalities from all around the world in those fields, I always wondered why despite the fact there is no dearth of talent in the country, I was unable to find any instance of Pakistanis working for the National Air and Space Administration (NASA).
I got in touch with Dr Mohsin Siddique, director of the theoretical physics department at the National Center for Physics, Islamabad.
Through him I had the privilege of connecting with Mr Mansoor Ahmed, a Pakistani astrophysicist, who has been associated with NASA for almost 35 years and is currently serving as the associate director of the Astrophysics Projects Division, as well as the programme manager for the Physics of the Cosmos programme and the Cosmic Origins programme at NASA Goddard Space Flight Center, Maryland.
Mr Ahmed has spent most of his career working at the Hubble Space Telescope (HST) programme in different capacities, including as flight operations manager and the project manager for HST operations.
He was the deputy project manager of the James Web Space Telescope (JWST) and the project manager of the Laser Interferometer Space Antenna (LISA) mission, a collaborative endeavour between NASA and the European Space Agency.
Here, I ask the impressive gentleman his success story, from his childhood in Peshawar to his work with NASA.
You were born and grew up in Peshawar. Can you tell us your family background? Do you recall any interesting story from your childhood/teenage years?
My father was a Subedar-major in the army. We lived in Peshawar, near Fort Bala Hissar.
For the first five years of my education, I went to a Christian mission school and from sixth grade onwards, I attended the Government Higher Secondary School.
Our house was across the street from Naaz cinema, the only cinema in the city that played English-language films. This is where I got my first exposure to films.
My father took me to see The Vikings and I was hooked from then on, even though, I didn’t really understand any English at that time.
My answer to the question ‘What do you want to be when you grow up?’ was: ‘I want to become the ticket collector at Naaz cinema so that I can see every film playing there.’
One day, I was visiting some relatives who lived right next to the Pakistan Air Force base in Peshawar and I witnessed an F-86 land on the runway. As the plane taxied, I could see the cockpit and the pilot.
The pilot waved at me as he passed by and right then my career goals changed. I wanted to be a fighter pilot.
At Government High School, a close friend of mine, Ayub, told me about the Air Force cadet academy in Lower Topa, a tiny town near Murree.
It consists of a boarding school that selects 60 children each year as pre-cadets, to prepare them to enter the air force flying academy after FSc. Ayub said he was applying and encouraged me to the same.
Fortunately, both of us got selected and we entered Lower Topa in May of 1966, at the age of 13.
In Pakistan it is not common for parents to support their kids to pursue astronomy as a profession. Can you tell us how much encouragement you received from your family during the early years of your career? Would you encourage your own child if they were to prefer the same profession?
I think there are two aspects to this question. Parents are concerned about the livelihood of their children when they grow up.
They are concerned whether their children will be able to earn a living and support a family. So, their tendency is to push their kids towards careers that are known to provide a good living.
Unfortunately, most often their preferences are also tainted by the apparent status of certain careers in our society. They end up ignoring the interests and aptitudes of their children in areas that may not rank high in the status hierarchy in Pakistan.
It is very likely that if allowed to pursue their own interests, children would really thrive in any career choice they make, whether it be engineering, medicine, music, business, sports, etc.
Taking astronomy as an example, even though there may not be too many job opportunities in astronomy in Pakistan, if a child is genuinely interested and has the right aptitude in the subject, encouraging them to pursue their passion may result in an illustrious career that might answer the most profound mysteries of the universe, possibly getting worldwide recognition.
I recognise it is a tough choice for parents, especially in Pakistan, where there is a stigma attached to certain careers and which are generally discouraged.
In my situation, I am not sure if my parents would have encouraged me to become a ticket collector at Naaz cinema but they definitely did not stop me from pursuing a career in the air force.
In the case of my children, I believe in allowing them to pursue their passions, be it astronomy, plumbing, or driving a taxi.
It is easy for me to say so because in the US, there is generally no stigma attached to any career and a person can make a decent living in any job, as long as they are willing to work hard for it. And if one has a career which follows their passion, it is easy to put one’s back into it.
The average person in Pakistan is not familiar with even basic scientific facts and interest in pursuing a career in the field of science is generally low. How do you think this situation can be addressed?
I believe the effort to instil within students a love for science needs to start at the very early stages of education. Children have a much greater curiosity and far more open minds than adults.
As we grow older, our perspectives get narrower and biased. We need to design science curriculums in a way that is engaging and easy to understand at the elementary level.
More emphasis should be placed on hands-on exercises and demonstrations, and not on memorisation of material. For this to take place, we need to train teachers on how to present the information in an interesting way.
I also feel that we separate science and arts students too early on in the stages of their educational development. Science courses should be made compulsory for a longer period – perhaps until the 12th year of education.
To further motivate young students into hopping onto the science and technical tracks, schools should encourage prominent scientists, engineers and technically-oriented professionals to visit and give talks about their interesting careers.
You have a bachelor’s degree from University of Maryland and a master’s degree from George Washington University in mechanical engineering. If you could do it again, would you take a different academic path?
This is a very interesting question to answer. First, I must admit, there is no direct path connecting my current career at NASA to my educational goals when I was a student.
As I mentioned earlier, my career goal was to become a fighter pilot. I was happily pursuing it in Lower Topa when I became unfit for flying due to my weak eyesight.
My parents had already migrated to the US while I was still in Lower Topa, and once unfit to fly, I was given the option to join my parents there. I exercised this option.
When deciding my educational path, I was still driven by the love of flying and figured I should study aeronautical engineering so that I can still work with jet planes.
As I started my bachelor’s degree, it became apparent that job opportunities in aeronautical and aerospace engineering were diminishing. The Apollo Program was coming to an end and there was no real vision that NASA was pursuing.
So my advisor recommended that I change my major to mechanical engineering. Out of all my courses, I enjoyed thermodynamics and heat transfer the most.
The US was entering a period of energy crisis and the government was focusing on commercialising alternate, renewable energy resources, such as solar and wind energy.
These needs were in line with my academic training and I was encouraged to continue my master’s degree in the area of energy resources. As luck would have it, NASA was in need of someone with heat transfer expertise, which opened the door for me into the organisation.
The point I am trying to make is that, where I am today is because of the circumstances that ended up in my favour. There were several occasions where I could have made different choices and pursued a course of studies resulting in a different career.
Who knows if that career would have been as exciting as the one I have now. So personally, I would not want to go back to my student days with the risk of not ending up where I am today.
You have spent most of your career working for the HST programme. Can you tell us what makes the Hubble Telescope so incredible?
Hubble is not only a scientific marvel but an engineering one as well. The idea of putting a telescope in space was a masterstroke.
Even though we have telescopes on the ground, they suffer from several limitations. They can only observe at night and for a relatively short duration until the sun rises again.
Our atmosphere also limits the wavelengths of light that the ground-based telescopes observe. With Hubble being above our atmosphere, it can see much more clearly and is not limited by the day-night cycle.
All the stars we see in our night sky with the naked eye all belong to our galaxy, Milky Way. Other galaxies are much farther away and the light coming from them is extremely dim.
To take their pictures, Hubble must stay pointed at the distant galaxies for a long time.
You can compare this to taking a picture in the dark without a flash. You must keep the camera shutter open for a long time, keeping the camera absolutely still or the picture will be blurry.
Hubble can stay pointed at an object billions and billions of miles away for days, while travelling around the earth’s orbit at 18,000 miles per hour. Over the period of the observation, it doesn’t jitter more than 0.000002 degrees.
These are some of the engineering capabilities that allow Hubble to unearth the amazing scientific discoveries that it has.
Do you have a favourite science result that came from Hubble, especially considering the fact that you have been an active part of the Hubble repair mission?
It is very difficult to narrow down the most favourite result from Hubble; there are so many beautiful pictures of exploding stars and merging galaxies that everyone would be amazed by.
The most profound image in my mind is the Hubble Deep Field image. We decided to point Hubble to a tiny, seemingly dark spot in the sky where there was nothing the naked eye could see.
Hubble stayed at that spot for 11 days, capturing any photons that might come from that direction to construct the final picture (remember my example of taking a photo in the dark).
When completed, it was amazing to see that the picture was full of bright objects, thousands of them. Each one of them was a galaxy consisting of trillions of stars.
That image illustrates how vast our universe is and makes one wonder our significance (or insignificance) in this universe.
The other great discovery, which is scientifically the most significant, is that of dark energy. Before Hubble was launched, the biggest question in astrophysics revolved around the fate of the universe.
Will it continue to expand because of the initial force of the Big Bang or will it slow down and start contracting due to the gravitational pull of the matter in the universe?
What our universe will do depends on the total mass in the universe, which defines the gravitational force in the system. Sir Edwin Hubble (whom the telescope is named after) determined the critical value of the mass (known as the Hubble Constant) that would define the fate of the universe.
If the mass is less than that value, then the universe will continue to expand, eventually cooling off and dying. If the mass is more than the value, then the universe will slow down, start contracting and end up as a singularity resulting in yet another big bang, with this cycle continuing forever.
One of the primary objectives of Hubble (the telescope) was to determine the Hubble Constant. Instead, what Hubble discovered was that the universe is neither slowing down nor expanding at a constant speed, but a few billion years ago, had started to expand faster than before.
This can only happen if there is some form of energy that appeared from somewhere, and is making the universe expand faster (Newton’s first law of motion). We call it dark energy because we have no clue what it is.
Solving the dark energy mystery has now become one of the top questions in astrophysics.
The JWST is an infrared telescope while Hubble is an optical telescope. Having also served as a deputy manager for the JWST, how do you feel about the future of Hubble? Is it true that JWST enjoys greater importance than Hubble?
Hubble and JWST are equally important tools for answering the astrophysics questions. Just like Hubble cannot see infrared light, JWST cannot see optical and ultraviolet light.
Together, they can solve more mysteries than either one can by itself. Hubble continues to be in perfect health. We predict that all its systems will still be functional until 2022 and most likely beyond.
JWST will launch in early 2019. The scientific community is eagerly awaiting when both of these observatories will work hand in hand.
What can you tell us about LISA? What do gravitational waves tell us and how would LISA further our knowledge about the beginning, evolution and structure of the universe?
Up until now, all of our astrophysical discoveries have been done by analysing the electromagnetic spectrum. The visible light, which the human eye can see, and Hubble is optimised for, is just a small subset of this spectrum.
The spectrum ranges from radio waves at one end and very energetic gamma rays on the other. We have satellites in space observing most of these wavelengths and together they have informed our knowledge of the universe to date.
But the electromagnetic spectrum is generated by the stars when they are born and start to emit electromagnetic radiation.
There were no stars at the time of the Big Bang, only elementary particles that coalesced together to form electrons and protons, which in turn formed hydrogen.
The hydrogen atoms started to coalesce to form blobs of hydrogen, eventually forming a mass large enough to have enough gravitational force to initiate hydrogen fusion at the core of this blob, thus igniting the blob into becoming a star that started to emit electromagnetic waves.
This process took hundreds of thousands of years. So, there were no electromagnetic waves during this time.
We call it the dark period because there was no light, and as a result, we can only predict theoretically what happened during that period.
Gravitational waves on the other hand were generated right at the start of the Big Bang because mass always existed and mass creates gravity.
The LISA mission is being designed so that we can see the universe with gravitational waves; a completely new way of looking at the universe.
With LISA, we will be able to look at the dark period from the very beginning of the Big Bang. We would also be able to see deep inside black holes from where electromagnetic light cannot escape.
While we are in the process of building LISA, there are several ground-based gravitational observatories coming into action already.
You visited Pakistan last year and spoke at the National Center for Physics, Islamabad. What did you observe?
I had the privilege of meeting young students in several institutions in Pakistan. I must say I was very impressed by their curiosity, intelligence and interest in astronomy and astrophysics, even with the limited resources available to them.
I was very encouraged to see that there were almost an equal number of girls and boys attending the talks. A lot of them were enrolled in PhD programmes in physics, which is not an easy subject.
I have made commitments to the leadership of these institutions that I will do my best in connecting these students with scientists and engineers at NASA who can provide them guidance in pursuing careers in space-based astronomy.
I have already obtained commitments from NASA scientists to give periodic lectures online to the interested students in Pakistan.