Happy birthday Hubble!

Twenty years ago, on 24. April 1990, the Hubble Space Telescope was launched into orbit. Since then, Hubble has given us many spectacular images, allowing us to explore and understand a little bit more the Universe.
Let us review some of the most relevant Hubble telescopes's science finding:

• Dark energy: the term "dark energy" refers to a force against the gravity; it is then responsible of the expansion of the Universe. By observing distant supernovae, the astronomers can study how the dark energy behaves, which is a key to understand the origin of the Universe.
• The age of the Universe: by measuring the brightness of pulsating stars it was possible to calculate their distance to the Earth. This parameter was used to determine the Hubble constant and the Universe's age, estimated to be around 13,75 billion years.
• Large galaxies: Hubble has registered images of galaxies when the universe was just 100 million years; these observations revealed that they were smaller than today's galaxies, concluding that large galaxies built up over time as smaller galaxies collided and merged.
• Extrasolar planets: planets out of our Solar System are called extrasolar planets. Hubble has detected many of them and made significant contributions to broaden our knowledge about them. For instance, its observations showed for the first time in history the composition of the atmosphere of one extrasolar planet.

+Info:
This post has been adapted from "Hubble space telescope's top science findings".
A complete review of select research papers can be found in this special issue of Nature.
More information about Hubble telescope and stunning images from it, can be found in the official website:

HUBBLE SITE

"Milestones of Photon History"

On occasion of the 50-year anniversary of the first demonstration of the laser (actually on the 16 May 1960), "Nature Milestones" highlights key discoveries in optics, which are based on the photon:

nature milestones: photons

A timeline is presented with small but compact articles to the different milestones. It presents a fast but interesting overview/ introduction over many important discoveries which are today everywhere used in optics. It is really worth to read it. If I am not wrong, I think the articles are even open access. You can either read it directly on the page or as pdf:

pfd of milenstones timeline (link)
pdf of all milenstones (link)

have fun

"Bringing Star Power to Earth"

A lot of high-energy laser facilities exist around the world, or are in planning. One of them is the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL):

National Ignition Facility (NIF)

NIF is a laser based inertial confinement fusion (ICF) research device. Thereby powerful lasers will heat and compress a small amount of hydrogen fuel to the point where nuclrear fusion reactions take place. The original purpose of the experiments at NIF are simulations of nuclear weapon detonations, as replacement for nuclear tests. However, the knowledge gained will be used too for a possible civil energy winning device by inertial confinement fusion. NIF will be probabyl the first ICF device which should produce more energy than was put in to start the reaction. We will soon know it.

some data:

number of beamlines: 192
energy per beamline: 18.75 kJ
center wavelength: 1053nm
pulse length: few nanoseconds
repetition rate: 4-6 shot per day
focusspot size: 5x of the diffraction limit
final costs: 3.4 billions (USD)
dimensions: nearly three soccer fields (around 21.368m²)
finished: end of march 2009

Like most of the very big constructions NIF had around 5 years of delay and the costs were 4 times more as budgeted. However it works now! In January, they have reported a laser energy of more than 1 mega joule!



NIF has a very good and informative page. Take some time to surf on it, it provides you with much more details as on this short post here. Below, I have put two links to "how NIF works" and the "video gallery". I liked the wikipedia entry too (it contains also over 70 references). Enjoy!

links:

• National Ignition Facility achieves unprecedented 1 megajoule laser shot
• how NIF works
• video gallery
  

• wikipedia entry
• german wikipedia entry
• article in science
• inertial confinement fusion
  

ToptiCalc, a (free) Photonic Scientific Calculator

Few days ago I crossed the way of this "photonic scientific calculator" from Toptica. It is a small calculator but containing interesting and helpful features for our work, small things which saves a lot of time ;). My favorite is the short pulses properties and chirp feature. Other features are:

• spectral unit conversion
• calculating spot sizes for focussed gaussian beams
• Fabry-Perot calculations
• reflection and diffraction at plane glass surfaces
• pulse train calculations
• short pulse properties and chirp
• conversion between linear and decibel scale

The calculator is made by the laser and optics company called Toptica and can be downloaded for free. However, you have to register (for free of course) but this should not keep you away. More detailed information about the calculator features can be found on their homepage, or click ToptiCal page. It is also interesting to watch their homepage, especially the applications page. Toptica is a well-known company in optics and offers many products and special solutions to research in optics (i am not sponsored by Toptica ;) )

free download (registration page)