Giant Magellan Telescope: Past, Present and Future of Space Exploration with Ground Based Telescopes

An in-depth conversation with Professor Wendy Freedman on the topic of space exploration with ground based telescopes. We discuss the history of space exploration using ground based telescopes, and try to imagine the future. Professor Wendy Freedman gives a detailed description of the features of the Giant Magellan Telescope, a ground based extremely large telescope under construction. We discuss the challenges involved in constructing the GMT and talk about the research opportunities that this extremely large telescope, once completed, will present.

Professor Wendy Freedman is one of the world’s most influential astronomers. Freedman is a professor of Astronomy and Astrophysics at the University of Chicago. She was also the chair of the board of directors of the Giant Magellan Telescope project from its inception in 2003 to July 2015. More than a decade ago, Wendy Freedman led a team of 30 astronomers who carried out the Hubble Key Project to measure the expansion rate of the universe. Her research now focuses on measuring both the past and present expansion rates of the universe, and on characterizing the nature of dark energy – the mysterious force that causes the universe to accelerate its expansion.

A Correction Note (Audio at 14:10 minutes): While discussing 60-inch telescope at Mount Wilson Observatory, we got the dates mixed up. The telescope was commissioned in 1908; the ‘First Light’ was on December 8, 1908. Astronomer Harlow Shapely used this telescope to make a number of observations about our galaxy the Milky Way. However it was not until 1917-18 that he concluded, based on his observations, that the Sun was not at the centre of our galaxy.

By |November 6th, 2016|Podcasts|
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New Horizons’ Pluto Flyby with Dr Mark Showalter

After traveling three billion miles, over a period of almost ten years, NASA’s New Horizons spacecraft is on its way to Pluto to perform first ever Pluto flyby. In this podcast Dr Mark Showalter, senior research scientist and principle investigator at the SETI institute, describes in detail the nature of this mission and what to expect in terms of scientific findings. Dr Showalter describes different features of the spacecraft, talks about the instruments on-board, and discusses the challenges involved as the spacecraft approaches Pluto.

Dr Showalter works on some of NASA’s highest profile missions to outer planets. He has been a member of Cassini Mission Science Team for nearly a decade, and is involved in the observations of Jupiter’s rings using New Horizons spacecraft. A frequent user of Hubble Space Telescope, Dr Showalter has to his credit the discovery of Jupiter’s outer most ring, Saturn’s moon PAN, and two moons and two faint rings around the planet Uranus.

Pluto is an interesting and complicated alien world. The Pluto system has four moons that orbit around the central binary system, which consists of Pluto and its large moon Charon; Dr Showalter explains the Pluto system in detail. Dr Showalter discusses the duration of the flyby and how close the spacecraft will come to Pluto and its moons; he then touches upon the following points:

  • What are main observations that the scientists intend to make and what are main expectations that the scientists have in their minds as the New Horizon spacecraft is about to flyby Pluto.
  • The New Horizons spacecraft has the capability to fly beyond the Pluto system. After the Pluto flyby, what is next for the New Horizons spacecraft? Where will the spacecraft go from there?
  • Whatever direction the spacecraft takes after the Pluto flyby, for how long will the spacecraft be able to communicate? How much fuel the spacecraft has and how long will it stay in the communication range? Will this spacecraft follow the footsteps of Voyager-1 and Voyager-2 and will continue travelling beyond the solar system?

As the spacecraft approaches Pluto, Dr Showalter and his colleagues are getting ready to manage a number of crucial aspects of this mission. Dr Showalter discusses his role in this mission. An interesting question that arises at this point is that, as the spacecraft approaches Pluto, if an anomaly is spotted, would the team have enough time to send a command to the spacecraft from such long distance, and would there be enough time to get any such command executed on time to deal with any anomaly.

Dr Showalter talks about the “Our Pluto Campaign” launched by SETI: SETI has invited public to help name features on Pluto. I finish this podcast by asking Dr Showalter about upcoming space missions that are being planned, and about new developments in his area of research.

By |May 20th, 2015|Podcasts|
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Are we alone in the universe? Search for Extraterrestrial Intelligence.

Are we alone in this universe? This is a fascinating question. While addressing this question Arthur C. Clark said, “two possibilities exist: either we are alone in the universe or we are not. Both are equally terrifying”.

In 1940 physicist Enrico Fermi posed a question, “if it seems likely the universe may host other life forms, how come we haven’t seen any signs”. This question is known as the Fermi’s Paradox that acknowledges apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilization and lack of evidence for such civilizations. Fermi posed this question in 1940, and in 2014 earthlings still don’t have any evidence that there is life out there.

Dr Jill Tarter holds the Bernard M Oliver Chair for SETI Research at the SETI (Search for Extraterrestrial Intelligence) Institute. Jill Tarter led project Phoenix which studied about seven hundred and fifty nearby star systems. She serves on the management board for the Allan Telescope Array; this is SETI’s new effort to search for extraterrestrial intelligence. She received two public service medals from NASA and was named one of the one hundred most influential people of the world for year 2004 by time Magazine.

I invited Dr Jill Tarter to this episode of Bridging the Gaps.

Question and topics that we touch upon in this podcast are:

  • The origin of the idea of using microwave radio signals to search signals from other solar systems.
  • Establishing SETI Institute: using human technology to detect possible existence of technology of extraterrestrial origin
  • Searching a radio or an optical signal that is intentionally engineered: how do we differentiate a signal that might have been intentionally and intelligently engineered from the signals that occur naturally.
  • Project Phoenix: perhaps the most sensitive and most comprehensive search for extraterrestrial intelligence
  • Cataloguing seventeen thousand star-systems that could possibly host habitable planet.
  • Process of identifying and differentiating those stars that have no possibility of hosting habitable planets from those stars that could possibly host habitable planets.
  • Initially the focus of SETI research was nearby habitable star systems, but now that a number of planets orbiting around starts (exoplanets) have been discovered, how has the discovery of exoplanets changed the SETI research?
  • SETI’s Dorothy Project (2010): a massive observational campaign covering a large number of planets detected by Kepler spacecraft
  • Mining and analyzing data collected as a result of large-scale surveys of sky as part to general astronomy to find ET signals.
  • Why don’t we make the search for extra-terrestrial intelligence an integral part of general astronomy?
  • Dealing with hoaxes: verification mechanisms that SETI has put in place in case a potential ET signal is detected
  • If an ET signal were detected how would SETI announce it? Would it be kept secret or would it be made public immediately?
  • Post detection task force and post detection protocol
  • How would the discovery of life out there impact earthlings? What would it change?
  • Recent research on extremophiles suggests that life at microorganism level has an amazing flexibility for surviving in extreme environments, there is an emerging view that not only life can exist in environments previously considered inhabitable, perhaps it can also travel through space from one planet to another planet.
  • Searching a habitable earth like planet out there
  • Why search for Extra Terrestrial Intelligence should be kept going?
  • Future research directions and expected developments in the field of astronomy and search for extraterrestrial intelligence

Resources:

By |December 28th, 2014|Podcasts|
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