How is the distance to stars measured?

Ever since I started writing about my research period at the Indian Institute of Astrophysics, I have been getting questions about space from many of my readers. So, instead of blabbering on about the proceedings of day 3, I decided to answer one of their questions.

The most common question I got dealt with measurements, a la, just how do we know something is this big, this far, this heavy etc. when we cannot even approach it, let alone handle it, to measure such properties. So I decided to write a brief, mostly qualitative, answer to this question about distances: how exactly do we know how far a certain star or planet is from us? Continue reading

Have we crossed the Great Filter?

One of the biggest arguments regarding the existence of aliens are the famous Drake equation and the equally famous Fermi paradox. I wrote about them four years ago and debated that aliens may still exist in spite of these arguments against them, and I still stand by that belief.

I was reminded of this again recently when I read about a so-called Great Filter theory that attempts to explain the standard sceptic’s question: if aliens exist, where are they? why haven’t we seen or met them yet?

Stemming from astrobiology, the idea behind the great filter is that a civilisation or species reaches a developmental wall it cannot cross. Continue reading

History or Physics?

Nobody can quite say which of these two men’s great words outdo the other. As Thomas Carlyle said, “History may be called, more generally still, the Message, verbal or written, which all Mankind delivers to everyman,” or, as Lord Kelvin himself put it, “When you can measure what you are talking about and express it in numbers, you know something about it.”

Although I knew the answer, I have been pondering over the need to study history ever since fifth grade when I first remember studying it. I still have no justification to study it except for the sake of entertainment. Continue reading

Our Universe: marble or wood?

If there is any fundamental quality of nature that has eluded physicists and sparked debates of a fearful scale, it is the question as to whether the universe has a simple (beautiful) underlying principle that runs quite everything in existence.

Undoubtedly, the dream of every physicist is, as Leonard Lederman creatively summed it up, ‘…to live to see all of physics reduced to a formula so elegant and simple that it will fit easily on the front of a T-shirt.” On a serious note, this highlights the strong belief in most physicists that nature is elegance and simplicity bundled into one. Continue reading

To commemorate my short tryst with the study of our Universe, I decided to compile a set of seven of

To commemorate my short tryst with the study of our Universe, I decided to compile a set of seven of the best photographs available, each describing one of seven phenomenon/bodies that have eluded physicists or struck them as remarkable.

In order, we have,

  1. Neutrinos (Super-K Neutrino Observatory)
  2. Wormholes
  3. Black Holes (‘Black Holes ain’t so black!’ courtesy Hawking, Stephen, A Brief History of Time)
  4. Supernovae (Eye Supernova)
  5. Saturn’s Rings
  6. Nebulae (Horse Head Nebula)
  7. Galaxies
Continue reading