Answered Questions


Q: Hello! I have been wondering about exoplanets lately, could they possibly harbour INTELLIGENT life? I would imagine microorganisms could fairly easily evolve under the right conditions, but intelligent
life? I would define intelligence as being self-aware. I would love to hear back from you if you have the time. Thank you so very much, hope you have a lovely day. Nicole 

A: Thanks for your question. There is a possibility that some exoplanets could harbor intelligent life. We have not yet detected any life, intelligent or other. You raise an interesting thought. Astronomers are looking for signs of *any* kind of life on exoplanets. For example, we are looking for a combination of gases such as oxygen, methane, carbon dioxide and water vapour in the atmosphere of an exoplanet in the habitable zone of another star. If you look at our Earth, you will find these gases, and hence we want to find something similar out there. This will only tell us that there is some kind of life on that planet, not necessarily intelligent life. To find intelligent life, other signatures may be needed. Maybe a rise of CO2 emissions over time or radio emissions.

– Dr Ravi Kumar Kopparapu, BMSIS & NASA Goddard

Q: 1. What are the constraints for planetary habitability? – Anuj Vasil 

A: This is an active area of discussion in astrobiology and the answer will keep evolving with more knowledge about planetary systems and the possible detection of life. Since the only planet we know inhabiting life in the Earth, most astrobiologists believe that a planet with oceans like the earth will most likely be habitable. The most popular definition today is that if a planet possesses climatic conditions so that it can sustain liquid water on its surface, the planet is considered habitable. The main factors determining habitability based on his definition is the number of stellar photons (starlight) falling on the planetary atmosphere and composition of the atmosphere itself. There are other physical and chemical factors which could sustain extremophiles (microbes living in extreme conditions) on other planets, which extends the definition of planetary habitability.
Dr Dimitra Atri, BMSIS 
Q: 2. What is the estimated time frame for inhabiting a different planet?
– Anuj Vasil 
A:  I am assuming the question is for human life. The timeframe would strongly depend on the similarity of the planet with the Earth. If a planet is very similar to the earth, very little effort would be required to create conditions suitable for human life and therefore can be accomplished very quickly. On the other hand, if the planet is very different from the earth, it would take a lot of time and effort to modify the atmosphere and other physical parameters such as atmospheric pressure, temperature, composition etc. to make it suitable for human life.
– Dr Dimitra Atri, BMSIS 

Q: Light is the fastest travelling thing in the universe. But imagine we were as big enough that whole solar system could seem no big than a pencil then we could easily see light travelling at a slower speed. What I meant here is that light can’t be the fastest travelling thing in the universe. I think more large the thing is more distance it can cover i.e time travels slowly to the Big things whereas faster to the tiny things. It’s just my assumption. Please give me
answer on this. Nikhil Ghulanawar

A: Light is not only the fastest traveling particle in the universe, but the speed of light itself represents an upper limit on the speed of any massive object in the universe. The reason that the speed of light is an absolute speed limit is that space and time themselves are really relative. As a person, object, or particle increases in speed, time slows down and lengths get smaller. So even as an observer moves closer to the speed of light, they will always observe light moving exactly at the speed of light. An object that approaches the speed of light also increases in mass as it gets faster, which means that traveling at the speed of light would require the object to have infinite mass! So it’s really Einstein’s theory of relativity that tells us that the speed of light does put an absolute speed limit on the motion in the universe.

–  Dr. Jacob Haqq-Misra, BMSIS

Q: Sir, the universe is said to be expanding, but, not with uniform velocity instead it is accelerating. If big bang was a blast then the universe should slow down. Was a bigbang a white whole? – Midhun 

A: Observations of the cosmic microwave background radiation indeed indicate that the universe is expanding an accelerating with increasing velocity. The increase in velocity is described by cosmologists as occurring during a period of “inflation” that occurred immediately after the Big Bang. Inflation is a theory that suggests a rapid period of expansion in this very early period of the universe, with a less rapid rate of increase occurring today. Most cosmologists accept the idea that inflation occurred in the universe’s past because results from missions like the Planck spacecraft and WMAP provide data that point toward a period of early inflation. The study of inflation remains a current topic of research in cosmology and astrophysics.

A white hole is a hypothetical area of space that is the inverse of a black hole, such that it cannot be entered from the outside. Very little is known about white holes, if they exist at all. Very little is also known about the conditions that caused the Big Bang, although some cosmologists have speculated on this idea. A few physicsts have explored the idea that black hole caused the Big Bang, and others have suggested that a white hole could also have worked. Nevertheless, there is currently no observational data to indicate whether or not this is actually where our universe came from.
 Dr. Jacob Haqq-Misra, BMSIS

Q: If interplanetary and interstellar space were an ecosystem of sorts and if non-planetary based creatures inhabited it and if such a life form or life forms were growing and swarming around tabby’s star and consuming its visible light, what waste products might be produced? Thanks for the speculation! If these “space critters” exist perhaps swarming occurs on such a timescale that very few might be visible to human 2016 technology.
Also, if space critters eat star energy could the waste be stepped down energy such as extremely low frequency.  Finally, would the equation be; human recording of Tabby’s star total emitted electromagnetic radiation equals expected emissions from that type of star minus energy used in space critters growth rate? – Jim Hale

A: The second law of thermodynamics tells us that it is impossible to convert from one form of energy to another with 100% efficiency, which means that there will always be some waste heat generated in any system. This is the reason that perpetual motion devices are impossible—because some energy will always be lost to the environment, no matter how many improvements are made.

For Tabby’s star, this suggests that any orbiting debris, whether cometary fragments or alien technology, should heat up as they absorb starlight and likewise emit waste heat in the form of infrared energy. The same goes for any system in the universe, including all biological life (humans too) and even hypothetical swarming, non-planetary beings. If there are beings floating around Tabby’s star as you suggest, then we should expect to see an excess of heat energy generated as a result.

Now, the amount of waste heat generated might be far less than we could detect, so it remains possible that we just don’t have good enough detection methods to identify the debris/whatever around Tabby’s star. The possibility also remains that whatever is causing the unexplained absorption around Tabby’s star could be (perhaps deliberately?) shifted into even lower wavelengths. Perhaps the waste heat is being reflected away from our vantage point, or perhaps extra work is being done to keep the system cool and beneath our detection threshold. The one thing we do know is that something is blocking light from Tabby’s star, and this energy has to go somewhere. This could tell us something new about how planetary dust works, or it could be energy used for a distant form of extraterrestrial life.

Whatever the explanation, whether weird life or unknown physics, the resolution to the mystery of Tabby’s star will be sure to teach us something new about the universe!

-Dr. Jacob-Haqq Misra, BMSIS


  1. I am an honors student at OPHS in Kansas City, Missouri. I am researching extraterrestrials for a senior exhibition and would appreciate any research assistance you could provide. My essential question is: Is the existence of extraterrestrials a hoax?
  2. If Earth were to send out a radio signal, and an ET were to respond, how long would it take for the signals to travel across many light years?
  3. What changes in the training of astronauts would occur if there was contact made with extraterrestrial beings?
  4. How many years will it take for Earthly technology to be able to colonize other planets if it is possible at all?

Daulton Coats


  1. There is no evidence as of today, April 3, 2016, of the existence of any life beyond Earth.
  2. Total time taken (years) = 2 x distance in light years + time taken to respond. For example, if one were to send a signal to a planet 100 ly (light years) away, and they take one year to figure out the content of the message and respond to it, it would take a total of: 2 x 100 + 1 = 201 years, to get a response back to the Earth.
  3. Any change is astronaut training is highly unlikely in case contact is made with extraterrestrials. Since the distance between stars is huge it could take them decades (see answer above) or more to travel to Earth.
  4. It is possible, but it is against planetary protection laws agreed upon by the international community. Currently, research is done on other planets with the aim of having minimal impact on the environment and avoid contamination as much as possible. If in the future a colonization effort is made, it could take decades to set up basic infrastructure (with current technology) to be able to support human life on that planet.

-Dr. Dimitra Atri, BMSIS

Q: I have always wanted to know more about the prospects of researching on hypothetical types of biochemistry. Also, how far is biochemistry as a subfield used in research for astrobiology? What kind of questions will it help solve or how far is it useful in this field? How would a typical career path be for an astrobiologist? It would be of great help if it were possible to contact somebody in direct association with this field. – Julia Jose

A: Biochemistry as a subfield in Astrobiology: Thank you for your question. Astrobiology is a field of research that encompasses areas of investigation all the way from cosmology to molecular biology, including sciences such as cosmochemistry, geochemistry, biogeochemistry, biochemistry, paleo-biochemistry, and paleobiology, to name some. In this vast breadth of sciences, biochemistry based studies have played a crucial role in, especially, deciphering processes and mechanisms that might have allowed for the transition from chemistry to biology, on the early Earth. THAT includes seminal work that was started by Drs. Stanley Miller and Harold Urey in 1953, which set the stage for prebiotic chemistry and biochemistry based work. In particular, Dr. Leslie Orgel, whom I consider to be one the fathers of the field of prebiotic chemistry, set the tone for the various kinds of studies that biochemists have since then undertaken to decipher the chemical origins of life! Biochemistry based and related studies have enabled delineating several processes including those relevant to understanding how precursors of informational and catalytic molecules might have been formed under certain early Earth conditions. Furthermore, it has shed light on how the resultant monomers could have self-assembled in particular niches to result in RNA, RNA-like molecules, and other small peptides. These are just a few examples from the very long list of things that the field of Astrobiology has ascertained from biochemical studies. Overall, biochemistry based work has enabled to discern several important processes fundamental to the emergence of life on Earth.

Hypothetical types of biochemistry reg.: Work from recent decades, in particular, has significantly strengthened the theory that propounds the plausibility of the existence of pre-RNA worlds. In here, alternate types of biochemistry are thought to have predominated, and these could have resulted as a consequence of certain selective pressures shaping the molecular landscapes prevalent then. Given this, the importance of studying other hypothetical types of biochemistry is implicit as they could enable the characterization of molecular alternatives that would have populated these proto- and pre-RNA worlds (for e.g. you could look up reviews by Dr. Hud and colleagues for more relevant information in this regard).

Career path: If anything, there isn’t a typical career path in Astrobiology, in my opinion! As has been detailed in previous answers, one can do a Ph.D. in Astrobiology related questions after having graduated from any field of science, engineering or even math! As Dr. Sanjoy Som has already alluded, it’s best if you could keep your education broad (see his answer for more details). After a Ph.D., if one wishes to pursue an academic career, one can seek a postdoctoral POSITION in any of the Astrobiology labs depending on their favorite area of research. Other career options typically include pursuing a career related to science education, science policy, science outreach, science communication and science administration. If you have more specific questions, you can email me directly at

Dr. Sudha Rajamani, Faculty at Indian Institute of Science Education and Research (IISER), Pune

Q: If the magnetic field of the Earth protects us from harmful space
radiation, is it theoretically possible to engineer a shuttle with
artificial magnetic field mimicking that of Earth to keep off
radiation for long-term space travel to, say, Mars? – Anonymous

A: There are two components which protect us from harmful charged
particle radiation from space, the earth’s atmosphere, and its magnetic
field. Out of the two, the atmosphere plays a major role in protecting
us from this radiation. More information on this can be found here:

However, in a spacecraft, the only reasonable solution is to generate
a magnetic field which is of much higher magnitude compared to the
earth’s, to compensate for the lack of atmospheric shielding. Such a
shield is currently in development at CERN, which aims to demonstrate
the effectiveness of this technique by the end of the year. More
information can be found here:

-Dr. Dimitra Atri, BMSIS

Q: I read online that a 20 mile wide comet could endanger the Earth in 2030. The claim was made by the author Graham Hancock. Should I be concerned? Here is the website:  Radja Callier

A: Author Graham Hancock claims that debris from the tail of a passing comet will endanger global civilization in the year 2030, but such a suggestion is completely inconsistent with the findings of modern astronomy. Hancock points to the Comet Encke as the source of this destruction to come; however, Comet Encke is a relatively small object measured to be of only about 5 km in diameter, which would be incapable of causing such widespread destruction even if it somehow were to strike Earth. NASA, the European Space Agency, and other organizations keep close watch on the skies for any objects that could threaten civilization or major cities, and astronomers are continually working to discover smaller and smaller objects that could pose risk to humans. Although smaller impacts, such as the Chelyabinsk meteor that entered Russia in 2013, could still catch us off guard, scientists have made detailed enough surveys of the sky to eliminate the possibility that any civilization-destroying impact will happen in at least the next several hundred years.

-Dr. Jacob-Haqq Misra, BMSIS

Q: I have completed my 12th recently. I want to go towards astrobiology and I want to know what subjects should I pursue my Bachelor’s degree? Where in India should I apply for such a focus? And could you also tell of a tentative career path after my Bachelors?     Nikhil Ghulanawar

A: At the moment, there are no dedicated courses available at graduate level for astrobiology in India. However, there are some labs in reputed institutions where active research is being done in astrobiology and related subjects. Here, you can pursue projects at graduate level and can also continue for a PhD. You may have to select the institute depending on your subjects in 12th class. There is the Indian Institute of Science Education and Research (IISER), Pune (prebiotic chemistry/origin of life) and IISER, Kolkata (origins and evolution of life), IIT-Roorkee (prebiotic chemistry), Kumaun University, Nainital (prebiotic chemistry), and Birbal Sahni Institute of Palaeobotany, Lucknow (geology/paleobotany). Astrobiology is a multidisciplinary branch of science and you can start with any stream like biology, chemistry, physics, astronomy, geology, or mathematics and become an astrobiologist.

– Dr. Preeti Nema, BMSIS

Q: I want to be an astrobiologist. I have an immense interest in space exploration. Which particular branch of engineering would you suggest I study which would help me become an astrobiologist?  – Pradip Chatterjee

Q: I am a student of class 12 with physics, chemistry, and biology. Is there any scope for me in the field of astrobiology? – Oshin Rawat

A: Hi Pradip/Oshin. I’m so glad you are interested in Astrobiology! Check out my answer to this question on SAGANet. As you’ll see, any kind of discipline will be good to study astrobiology, including engineering. Just make sure your education is broad (for example, as an engineer, take a biology and/or a geology class if you can, and make sure to know programming and statistics). If your university doesn’t offer such courses, check out websites like Coursera to see what is offered. In my view, think of astrobiology as a scaffolding that allows scientists from different disciplines to talk to each other and answer some of the most fundamental questions in science, so it doesn’t really matter what engineering program you follow or which science field you pursue, as long as you gear your research towards astrobiology. Good luck!

– Dr. Sanjoy Som, BMSIS, NASA-AMES