“Cassini's Own Discoveries Were Its Demise.”

My God, it’s full of stars

- Dave Bowman, 2001 a Space Odyssey

When you look up from a dark site on a clear moonless night, the sky appears full of stars, almost too many to count.

It turns out that, with the naked eye, one can see anywhere between 5000 to 10000 stars, depending on whom you ask and how they estimate this number and just half of that on a given night because the Earth gets in your way. Still a lot but really nothing when you consider there are billions - maybe hundreds of billions of stars in our Galaxy and trillions of galaxies in the Universe.

It’s a completely different matter when you use optical aid. A pair of 50 mm binoculars can pull in some hundreds of thousands of stars; a small - say 80 mm telescope - like mine-can “ see” millions.

And here is an example. This is the much loved deep southern object known familiarly as 47 Tucanae- Tuc 47 to friends- and it is what is known as a globular cluster.

It contains over a million stars - I am unable to determine what the latest estimate is- a couple of decades ago we used to say it contained half a million stars but that estimate has since been upped.

It’s the second largest of this type of cluster- there are around 150 of these distributed in a halo around our galaxy that we know of.

And quite spectacular in a telescope of any size. It cannot but bring to mind Dave Bowman’s famous exclamation in “2001 a Space Odyssey “

Imaged from my backyard last weekend; an image salvaged despite the usual trials and tribulations that beset the amateur astrophotographer including tangled cables and the camera slamming into the tripod leg and so on and so forth.

Given the long weather forecast it’s going to be slim pickings this summer so you take what you get

What would it be like to live on a planet within a globular cluster? In 1941 Issac Asimov wrote a great short story “ Nightfall “ imagining just that. Highly recommended if you have forgotten it

Sadly the Hubble Space Telescope looked for planets in Tuc 47… and found none. So we have no evidence that planets form within these globular clusters- thus far

https://flic.kr/p/2mGS9cC

Created using still images taken by the Cassini spacecraft during it’s flyby of Jupiter and while at Saturn. Shown is Io and Europa over Jupiter’s Great Red Spot.

NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill

Cover design for an Italian reprint of Isaac Asimov’s “Foundation Trilogy” by Gabriel Björk Stiernström. 

Images of the Earth and the moon above the Rings of Saturn taken by Cassini on April 13, 2017.

Credit: NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill

⦕⁅⁅⁅ɔ  ⦕⁅⁅⁅ɔ  ⦕⁅⁅⁅ɔ  ⦕⁅⁅⁅ɔ  ⦕⁅⁅⁅ɔ

you have encountered a group of trilobites! reblog to help them on their journey

Hiking to the largest Ammonite in the world!

Video description:

Titanites lived during the Late Jurassic Period and had a shell diameter of around 137 centimetres! surprisingly it wasn’t the largest ammonoid, as some species such as Parapuzosia could get over twice as large!

There were also some plant fossils around the area of this site!

the red eyeshine of the alligator occurs when light enters its eyes, passes through the rods (light receptors) and cones (color receptors) of the retina, strikes a membrane behind the retina called a tapeatum, and is then reflected back through the eye to the light source. most of the animals with eyeshine are, like alligators, night hunters who must make use of limited light. photos by larry lynch and david moynahan

cosiscience

Walking dinosaur, Columbus Interactive Science Museum