Image credit: The Cosmic Perspective / Jeffrey O. Bennett, Megan O. Donahue, Nicholas Schneider and Mark Voit.
From Azri our original question-asker on the topic of how long the Universe has been accelerating: Just when you mentioned that the universe was almost 7.8 billion years old when started accelerating: I think that calculation is based on a constant” cosmological constant! what if Dark energy was dynamical !? can one expect more than 8 bill years, lets say almost recently!
If dark energy changes over time which it
may then it s conceivable that the Universe began accelerating either slightly earlier or later than this. If dark energy was weaker in the past and is stronger now, then the Universe will have been accelerating for
“They do not see what lies ahead, when Sun has faded and Moon is dead.” -J.R.R. Tolkien
Someday, the Sun will expand, engulfing Mercury and Venus, and then some. Will we survive?
October 29, 2017
What better way to say farewell than with a slew of costume pictures from this year s (coming) Halloween? Happy Halloween 2017! From Ethan Siegel and Starts With A Bang. Keep looking to the Universe. And we ll have a lifetime of wonderful things to still explore.
Goodbye, Scienceblogs,…
October 28, 2017 Delay is the deadliest form of denial. -C. Northcote Parkinson
Every massless particle and wave travels at the speed of light when it moves through a vacuum. Over a distance of 130 million light years, the gamma rays and gravitational waves emitted by merging neutron stars arrived offset by a…
October 27, 2017
“On what can we now place our hopes of solving the many riddles which still exist as to the origin and composition of cosmic rays?” –Victor Francis Hess
Next week, I’ll be at two days of the official Star Trek convention in Las Vegas, on August 3rd and 4th, and the full schedule is now online! While the Perseids are coming up, followed by the total solar eclipse, there s still a whole lot to do before then. You ve had a lot to think about and a lot to say, so let s get right into our comments of the week! The particle tracks emanating from a high energy collision at the LHC in 2014. Although these collisions are plentiful and incredibly energetic, they have not yet yielded any compelling evidence of physics beyond the Standard Model. Image credit: Wikimedia Commons user Pcharito.
There s so much more that s on its way, including our second podcast coming next week, an upcoming holiday giveaway for the lucky submissions chosen for Ask Ethan, and some more spectacular articles about how the Universe came to be, and how we know it. (Oh, and we ve also almost unlocked the next Patreon reward, for real! Let s make it happen before 2015 is out!)
Now, join me as we jump in to our Comments of the Week!
From Dean on the UFO seen from the ISS: As I explain, however, this is simply light reflecting off of the ISS’s HDEV module, nothing more complex or extraordinary than that.