Chicken Little was even more wrong.

Turns out the sky is not falling. Not really news, in astrophysics. But, hold your chickens, Johns Hopkins announced today that data from both the Hubble, and Planck instruments, backed up by a number of co-operating ground observations show that the Hubble Constant is not constant, and may have been increasing since the earliest (most distant) observations made.

The discrepancy is a medium warm, to hot topic in cosmology. Stringent examination of possible methodological errors in the value of the rate of expansion at the first observed era, and much more recent periods (much closer targets.) are significantly different (9%).

New methods of using the still functioning Hubble Telescope have allowed a very robust new set of observations of the Magellanic Clouds, and the Cepheid variables in them confirm the discrepancy between its measurable Hubble shift, and the also very robust datasets from the Planck instrument, and the VLA, are strong evidence that the expansion of the universe is accelerating, and has been since at least shortly after the Cosmic Background Radiation was released.

News release here: New Hubble measurements confirm universe is expanding faster than expected -- ScienceDaily

Following the links is hard so far, and involves some pay walls. I cannot recommend methods of defeating those proprietary defenses against . . . well . . . me.

Since I don’t see a question here, let’s move this to MPSIMS.

Colibri
General Questions Moderator

This has been known for 20 years.

Neil deGrasse Tyson had some interesting observations about this. I probably am not doing it justice, but the upshot was:

  1. In some period of time, the acceleration will result in no galaxies being observable from the Earth. Beings at that time will have no idea that other galaxies ever existed (barring really good historical records from us).

  2. What things existed before we came along to observe in the present time? Have we missed something vital about our universe because it is far enough to have accelerated beyond our ability to detect?

I hope I got those questions right. IANA Physicist/Cosmologist/Astronomer.

The crux of the observation is that recent expansion and deep time expansion do not seem to line up. So there’s something causing an acceleration in expansion. It’s a neat problem.