Lecture Black Holes and The BlackGEM telescope Array

Today I attended a lecture on black holes via Radboud Unuiversity and provided by Prof. Dr. Peter Jonker, who is also the Project Scientist of BlackGEM (see below). The lecture started with a good overview of the special and general relativity theory in order to explain the concept of a black hole. A couple of things I will be remembering:

- nothing is moving faster then light (speed of light); when reading this different, nothing or an empty space can move faster then light.
- Accretion onto a black hole is the most efficient process for emitting energy from matter in the Universe, releasing up to 40% of the rest mass energy of the material falling in. As a comparison, nuclear fision and fusion convert mass into energy by 0.08% & 0.7%

- when a star has a mass so large that the escape velocity exceeds the speed of light, it's called a dark star according newtonian laws; the same dark star is described as a "hole" when applying general relativity by introducing space-time curvature.

BlackGEM is a wide-field telescope array, located ar ESA La Silla Chile, dedicated to measure the optical emission from pairs of merging neutron stars and black holes. BlackGEM will be triggered by the Advanced LIGO & Virgo gravitational wave detectors. ic.

BlackGEM will start with 3 telescopes each 65cm diameter, and each equipped with a 110 Mpix camera, consisting of a single 10.5k x 10.5k CCD sampling the sky at 0.56 ”/pix.

Exoplanet Watch Program

Researchers confirmed an exoplanet, a planet that orbits another star, using NASA’s James Webb Space Telescope for the first time. Formally classified as LHS 475 b, the planet is almost exactly the same size as our own, clocking in at 99% of Earth’s diameter, located at a distance of 41 light years from Earth and orbiting every two days around it's red dwarf star which has a temperature half of our Sun.

But could you observe an exoplanet from your backyard? I made some progress with imaging Quasars up to redshift z=2.038 (see this link) and of course the first discovered quasar 3C 273 (see this link). But a next challenge could be the observation of an exoplanet from your background. Well, according to different websites it would be possible. I found a couple of interesting website which I will be using to get more information and which I will share below. 

 https://exoplanets.nasa.gov/

https://www.aavso.org/

https://www.afastronomie.fr/

Minkowski Hermann

Today, Jan 12, we remember Hermann Minkomski's death anniversary. Hermann Minkowski was a Jewish German mathematician. He used geometrical methods to solve problems in the special relativity theory of Einstein. Minkowski is perhaps best known for his foundational work describing space and time as a four-dimensional space, now known as "Minkowski spacetime".

See also my blog on Minkowski Diagram: https://pascalhilkensastropage.blogspot.com/2020/10/twin-paradox-minkowski-diagram.html

130.000 Visitors

 

Since the start of my blog on December 2012, I'm counting an amazing number of 130.000 visits to my blog. Thank you all for those visits in which I made a small contribution to promote astronony, solargraphy and related sciences.

Sun Full Disk AR3181 and AR3182

 

The Sun today, January 7, 2023 with Sunspots AR3176, 3177, 3180, 3181, 3182 and 3183. The picture was taken with DSLR Nikon D7500 on TAL200K with ND3.8 and OIII filter. The picture is a mosaic of two pictures which are combined using ICE (Image Composite Editor). Sharpening is done with IMPPG and final editing using CS4. False colour are added.

The Sun in OIII

Between the clouds I could take some pictures of the active Sun. Pictures taken using my OIII filter.

Setting: TAL200K f/8.5, Nikon D7500, ND3.8 filter and OIII filter

Software: CS4

Planetary Astronomy Book

Arrival of my book on how to observe and image planets.