Me: true, but depending on the type of observation made, and post observation analysis by experts (astronomers for instance), one can rationally rule out certain things in certain circumstances. Often we can say that it cannot possibly be X (Venus) or X (aircraft) or X (meteors) leaving the observation something outside what we can easily categorise. The question here is whether the observation represents new phenomena without having to answer using the ET hypothesis. IMHO some observations certainly appear to represent new phenomena - following this line of conservative arguing. I wonder if Tyson thinks there is nothing worth investigating or says that there is nothing worth investigating, whilst understanding the opposite is true.
An online response to my comment: Traveling at the speed of light, which is impossible, it would take around 100,000 years to reach the earth from the nearest possibly inhabited planet in our galaxy. Then one could ask why make such a trip in the first place and if such a journey was accomplished why not announce one
Me: I was addressing the observations without referencing the ETH - just as Tyson was doing with his conservative argument. In this case speculation about ETs is a secondary matter compared to whether new phenomena have been observed in the atmosphere. It's a classic case of not putting the cart before the horse. Thus when unusual objects are observed, being scientifically minded, we need to evaluate what was seen or recorded first and then consider very carefully what known phenomena they may correspond with. When we have good observations of phenomena that do not correspond with known phenomena then that should be considered a mystery to science and worth further investigation. If we find data indicating new phenomena we can then speculate as to its origins - whether it is a local natural occurrence or whether it may represent an impossible extra solar incursion.
And, as scientists investigating the natural world, if we were able to send probes to other star systems, of which there are estimated to be 2000 habitable worlds within 60 light years of the Earth (based on analysis of the Kepler space telescope data published in the Proceedings of the National Academy of Sciences), we would logically avoid direct contact with any intelligent life so as to make observations on their existing society. If we did announce ourselves our probes would risk upsetting their culture and we'd lose the chance to make predictions on how intelligence species evolve - whether certain types of eco systems generate intelligent life forms that self destruct. On planets with no intelligent life then we could probably be more adventurous without causing any culture shocks.
Also, if there is intelligent life on the planets in our neighbourhood and they have technology 100,000 years ahead of us then they may be able to bridge the gap between the stars. And if you travel at the speed of light for 100,000 years you would have crossed the entire galaxy. Accelerating at 1g you could attain near light speed in about a year. However, avoiding obstructions would certainly be an issue. Surprisingly Wikipedia's entry on 'faster than light' travel provides a good summation of space travel to nearby stars at close to light speeds and effects of time dilation:
QUOTE: Since one might not travel faster than light, one might conclude that a human can never travel further from the earth than 40 light-years if the traveller is active between the age of 20 and 60. A traveller would then never be able to reach more than the very few star systems which exist within the limit of 20-40 light-years from the Earth. This is a mistaken conclusion: because of time dilation, the traveller can travel thousands of light-years during their 40 active years. If the spaceship accelerates at a constant 1 g (in its own changing frame of reference), it will, after 354 days, reach speeds a little under the speed of light (for an observer on Earth), and time dilation will increase their lifespan to thousands of Earth years, seen from the reference system of the Solar System, but the traveller's subjective lifespan will not thereby change. END QUOTE
________________________________________
The overall problem with Tyson's declaration that UFOs do not necessarily equate to aliens, and that your own lack of expertise requires you to not jump to conclusions, and that the sightings could be anything mundane, is the wrongful implication that ALL unusual sightings do not represent new phenomena. Some sighting reports are well documented and may show evidence of real phenomena. Nuclear physicist Stanton Friedman points out similarly erroneous statements regarding this subject made by Carl Sagan:
Source:
http://spookyweather.blogspot.com/2014/01/response-to-neil-de-grasse-tyson-quote.html
