http://www.youtube.com/watch?v=wFpeM3fxJoQ

Here are some VLT links to explore

• wikipedia entry
• the VLT website
• series of images from the BBC
• the VLT’s laser guide
• ESO’s top 10 discoveries

You can get a pdf summary of the VLT from the European Southern Observatory (ESO), the organisation that runs the VLT, by clicking on the download link below.

image by NASA

A few weeks ago we were all ready to look up for an evening sighting of the space shuttle Endeavour as it separated from its external fuel tank while passing over the UK.  That launch was delayed but NASA is set to try again today.

Endeavour is the newest vehicle in the shuttle fleet.  It was built as a replacement for Challenger.  This will be Endeavour’s last mission and its task is to carry the Alpha Magnetic Spectrometer (AMS-02) up to the International Space Station.

Launch is scheduled for 1.56pm UK time and you can watch it live on NASA TV.  Alternatively, you can watch the launch as a webcast from CERN, starting at 1.45pm.

AMS is designed to search for antimatter, a substance first proposed by British Physicist Paul Dirac.

Physicists believe that there should be a balance between matter and antimatter .  The problem is that we live in a universe that seems to be made from matter, not matter and antimatter, so the question is…

where did all of the antimatter go?

Particle physicists at CERN’s Large Hadron Collider have an experiment that is looking for an answer to this question.  The particle physics research teams at CERN were given the job of building the AMS, which was transferred to the Kennedy Space Centre earlier this year.

The videos below are from CERN’s multimedia library for the AMS project and will give you an idea of the role of AMS.  The first film is less than one minute long and designed to act as a trailer for the project.  The second is longer (15 minutes) and has several interviews with key project staff.

This air resistance is just like any other form of friction – it converts kinetic energy into heat energy.  The effect of this heat energy is demonstrated in this video clip taken by a Canadian police car camera.  It shows a meteorite burning up in the atmosphere above Edmonton.

http://www.youtube.com/watch?v=e_2aX-784sw

Thankfully most meteorites do burn up in the atmosphere, although the dinosaurs were not so lucky.

The high temperatures created during re-entry ionise the gas around the orbiter and this is often seen as a bright light in NASA cockpit videos, such as the one shown below.

http://www.youtube.com/watch?v=TOieURpnbm0

To protect the vehicle and its crew from these high temperatures, the underside of the orbiter is covered by a layer of heat resistant tiles called the thermal protection system.  This NASA clip explains how the tiles are constructed and arranged on the underside of the orbiter.

http://www.youtube.com/watch?v=RJzyB_qEWyU

When Columbia was launched in 2003, something fell against the insulation on the left wing and knocked off some of the tiles.  This hole in the thermal protection system caused Columbia to explode over the US as it re-entered the atmosphere.  There is a wikipedia article about the Columbia disaster.

Video footage of NASA’s Houston control room from the morning of the disaster was included in the BBC Horizon documentary Final Descent – Last Flight of Space Shuttle Columbia.

WARNING: This last film is an excerpt from the Horizon programme and includes genuine cockpit video that was found in the wreckage, with some clips of the crew’s final minutes before they were killed.

http://www.youtube.com/watch?v=Do8TyMtgzso

There is a good description of the Space Shuttle at How Stuff Works.

In this video, astronomers talk about how they can use the line spectra from stars to classify them into different categories.

http://www.youtube.com/watch?v=R6_dZhE-4bk

http://www.youtube.com/watch?v=bJv55ebJbhs

Here are 2 short videos to remind you how to draw a ray diagram.  The first video is an introduction to ray diagrams.

how to draw a ray diagram from mr mackenzie on Vimeo.

The second video looks at a ray diagram when the object is less than one focal length away from the lens.

ray diagram for objects closer than 1f from mr mackenzie on Vimeo.

Once the ray diagram is complete, we need to describe the image that has been formed.  The description must tell us about the size, orientation and type of image that is formed.

Size
If the image is larger then the original object, we say the image is magnified
If the image is smaller than the original object, we say the image is diminished.

Orientation
If the image is the same way up as the object, we describe it is upright.
If the image is upside down compared to the object, we describe it as inverted.

Type
If the object and image are on opposite sides of the lens, it is a real image.
If the object and image are on the same side of the lens, it is a virtual image.

http://www.youtube.com/watch?v=vhwD0gyYgvA

There’s lot of information in the clip.  The commentator tells viewers about the liquid rocket fuels (hydrogen and oxygen), the water dousing system used at liftoff and explains each stage of the rocket’s journey presentation.

The French W3B satellite was designed to provide TV, radio and internet services to Europe, Africa and the Middle East.  At 13:11 in the film, we can see the release of W3B.  Notice that the left side of the screen shows an altitude of only 1,200km at this point. This is not high enough to achieve geostationary orbit and the satellite must use its own propulsion system to reach an altitude of 36,oookm.

Unfortunately, W3B experienced propulsion problems and was unable to climb to 36,000km.  There is a BBC news report of the mission failure here.  The photograph in the BBC article is particularly good because, although the satellite is wrapped in protective film, we can clearly see two curved reflectors wrapped in silver film.

Apollo 11 Saturn V Launch (HD) Camera E-8 from Mark Gray on Vimeo.

Today we looked at emission spectra from different light sources; mercury, sodium, cadmium and oxygen discharge tubes, using a handheld spectroscope.

Here is a video that shows you how to make a basic spectroscope at home.  There are lots of guides like this online.  You might prefer to make a larger spectroscope by using a Pringles tub rather than an old toilet roll holder as the main tube.

http://www.youtube.com/watch?v=YStZk2zANvk

I have attached the handout on colour and emission of light from different elements below.