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Total eclipse of the Moon

By Oli Usher, on 28 September 2015

lunar-eclipse_2015-09-28

Last night saw both a supermoon (the Moon’s closest approach to Earth, in which it appears about 14% bigger than it does at its most distant), and a lunar eclipse, in which the full Moon passes through the Earth’s shadow.

During a lunar eclipse, the disc of the Moon progressively goes from bright white to a deep red: when in the Earth’s shadow, the only light illuminating its surface is the light that is bent through Earth’s atmosphere. This light – effectively, the light of all the sunrises and sunsets on Earth – is red because blue light is scattered in Earth’s atmosphere.

This sequence of photos was produced by Theo Schlichter, Computing and Instrumentation Officer at UCL’s observatory, using a Canon EOS450D camera and a 200mm lens. The composite was produced by Dr Steve Fossey.

First person: 8.3 magnitude earthquake hits Chile

By Ofer Lahav, on 23 September 2015

A combination of high mountains, clear skies and bone-dry deserts makes the north of Chile one of the world’s best places to observe the sky. Numerous international observatories are located there, and astronomers from around the world frequently travel there to carry out their research. Ofer Lahav, Perren Professor of Astronomy at UCL, was there during the magnitude 8.3 earthquake of 16 September. This is his personal account of the events.

Cerro Tololo Inter-American Observatory. Photo: Ofer Lahav

The Blanco 4-metre telescope at Cerro Tololo Inter-American Observatory. Photo: Ofer Lahav

The Earthquake started on Wed 16 Sep at 19:54 (local time), just as we were preparing for the start of DES (Dark Energy Survey) observations.

We left the telescope immediately, and moved to the shaky ground outside the dome. Eventually we were evacuated from there to the CTIO dining hall.

The team was evacuated to the observatory's dining hall - Ofer Lahav is leftmost.

The team was evacuated to the observatory’s dining hall – Ofer Lahav is leftmost.

After-shocks continued throughout the night, but the oscillations finally decayed.

The following morning was sunny and quiet. Observations resumed the following night.

Boulders dislodged from the mountainside and fell onto the road near the observatory. Photo: Ofer Lahav

Boulders dislodged from the mountainside and fell onto the road near the observatory. Photo: Ofer Lahav

I left next morning as planned, flights were on schedule.

We were all impressed by the way the observatory staff handled the situation efficiently and calmly.

It is re-assuring that the system, in part assembled at UCL, is working so well – the only obstacles between the DECam instrument and the galaxies are the Earth’s atmosphere and quakes…

The astronomers who didn’t stop for a missile strike (or a flat battery)

By Oli Usher, on 18 September 2015

This remarkable document comes from the observing log of the University of London Observatory. The observatory is now a UCL teaching facility and part of the Department of Physics & Astronomy, but at the time was an important research facility.

It reveals the effect of the Nazi bombing of London during the second world war.

paper

UCL’s Bloomsbury campus was severely damaged in raids early in the war, with the Library’s dome destroyed and the historic buildings around the main quadrangle all gutted by fire.

bombdamage

Relentless bombing from aircraft early in the war, then by V1 and V2 missiles later in the war brought the conflict close to Londoners, and the unperturbed tone of the log makes clear how commonplace it had become – even in the quiet suburban environment of Mill Hill, where the observatory is located.

The log reads:

1944 August 3

Opened 21h. Sky clear.

Found red light on spectrograph not workingm, owing to plug having been left in and battery run down. Set on γ Cas with the help of dark room red light.

I started exposure at 21h 44m GMT.

Flying bomb exploded very close and shifted star in declination out of the field.

Star recovered and exposure restarted at 21h 47m GMT.

Just after starting the second time, a second flying bomb exploded. This was more distant and though it shifted image from the [spectrograph] slit, star did not go out of field and was quickly recovered.

Exposure ended 22h 07m GMT.

Exposure time = 20m.

Plate developed.

Closed 22h ½.

EMP CCLG

The event was a V1 flying bomb strike on nearby Hendon, which killed eight and destroyed 193 houses.

The signatures on the end of the document are of historical note too – alongside CCL Gregory, the director of the observatory, was EM Peachey. She is better known today under her married name of Margaret Burbidge. At the time, she was a young astronomer who had just passed her PhD, but she went on to become one of the preeminent astrophysicists of the twentieth century.

The observatory will be holding a one-day astronomy event in the Quad on 2 October, and an exhibition of astronomical images produced by UCL staff and students using its telescopes will be held along the walls of the North Cloisters throughout the term.

 

 

Why chemistry labs need expert glassblowers

By Oli Usher, on 11 September 2015

flask

Chemistry labs need skilled glassblowers to produce some of the intricate, bespoke glassware for some of their experiments. This item, produced by one of UCL’s glassblowers, is designed to be placed on a heat source so it can distill liquids and deposit them in ampoules along its long stem.

The flask’s design includes bell-shaped edges inside to encourage the liquid to evaporate evenly. The gas then cools and condenses inside the long stem, collecting at the end. When enough has collected there, the end of the stem can be melted off, sealing the liquid safely inside.

Time turns backwards at the Spark Festival

By Anna Lambert, on 28 August 2015

While real time travel may be theoretically possible, it almost certainly won’t happen in our lifetimes. However, at the Spark Festival this weekend, the Chalkdust team will have a very surprising demonstration where we can turn time backwards.

For a sneak preview, watch this video of a Taylor-Couette cell (sound not necessary):

Surprised? I certainly was when I saw it for the first time.

For those who couldn’t watch the video: at first, blobs of coloured syrup are dropped into some clear syrup. Then the colours are mixed up by turning a tube inside the cylinder, until they look all brown. However, the tube is then turned back the other way, and the coloured liquid completely unmixes, ending up in the same blobs as they started. It looks exactly like the video has played backwards. It’s called reversible flow, and we’re very excited to have our own Taylor-Couette cell at the festival, where people of all ages can have a go at turning back time.

Airplane_vortex_editNow you might be thinking – what’s that got to do with maths?

Read the rest of this entry »

A balanced view of radon

By Oli Usher, on 27 August 2015

IMG_0786

Thin, fragile, light, and barely visible against the padding that keeps it intact, this object is nevertheless reflects an important period in the history of chemistry – a period in which UCL led the world.

Around the turn of the 20th century, UCL’s chemistry labs saw most of the key discoveries related to the noble gases. William Ramsay isolated helium and argon here in 1895, and went on to discover krypton, neon and xenon in 1898. Over the next few years, experiments at UCL proved that radon, discovered by Friedrich Dorn in Germany, also belonged to this group. (Ramsay won UCL’s first Nobel Prize for his work on these gases.)

The delicate quartz balance in the image above is one of the most important pieces of apparatus used in this research on radon. It was used by UCL chemist Robert Whytlaw-Gray to weigh a sample of radon and determine its density for the first time. A schematic of the balance is shown below:

Print

The balance held a tiny sample of radon in the chamber on its right, and was balanced inside a vacuum flask with a weight attached to the balance’s other side. Despite the tiny quantity of gas involved, this was enough to determine radon’s properties.

It is held by UCL’s chemistry collections, along with other artifacts relating to this period in UCL’s history, including William Ramsay’s Nobel Prize medal and citation.

 

Cantilevers for diagnosing disease

By Oli Usher, on 21 August 2015

cantileversThis tiny device, developed by researchers at the London Centre for Nanotechnology, could soon help carry out difficult medical diagnoses.

The tiny rods, or ‘cantilevers’, are coated with molecules similar to those in our cells, which have been made sensitive to various diseases. In their work, the team have successfully made coatings which react with molecules that are part of HIV, the antibiotic Vancomycin, and blood anti-clotting factors (for haemophilia).

When in the presence of one of these molecules, the cantilever bends (as seen above), revealing the diagnosis.

cantilevers2

The most distant galaxy

By Oli Usher, on 6 August 2015

EGSY8p7 The blurred, faint, orange speck at the centre of this image may look unremarkable, but it is the most distant galaxy ever to have been confirmed by scientists. Called EGSY8p7, the galaxy was identified by UCL PhD student Guido Roberts-Borsani in the Hubble image above, based on its unusually reddened colour profile.

Followup observations using the WM Keck observatory by a team including Roberts-Borsani and UCL astrophysicist Richard Ellis have confirmed the find. Splitting the light into its component colours, the spectrograph at the observatory showed that the galaxy’s spectrum was shifted far towards the red end of the spectrum by the expansion of the cosmos. This ‘redshift’ is an unmistakeable sign of an extremely distant object.

It is at a redshift of 8.68, meaning we see it as it was when the Universe was only about 4% of its current age. Its light has been travelling for over 13 billion years on its long journey to us.

Read more about the research.

10 Questions

By Christina Campbell, on 30 July 2015

In this monthly feature, the Institute of Biomedical Engineering (IBME) interviews our researchers, academics, students, clinicians, affiliates and partners to find out a little more about who they are and what they do.

This month we interviewed Professor Kwang-Leong Choy, Director of the UCL Institute for Materials Discovery and Professor for Material Discovery at UCL. We asked her 10 questions around her research, career and personal life. Here are her answers….


 

IMG_76241) How long have you worked as Director of the UCL Institute for Materials Discovery and Professor for Material Discovery at UCL?

Since February 2014

2) Can you please describe what it is you do?

I work in Materials Discovery, so we work with new materials, new processes, materials with improved/enhanced performance, new applications of materials, and we link theory with practice.

3) What brought you to the world of science/engineering/medical technologies/medicine?

I’ve always wanted to make a difference in the science, engineering and medical fields. Now I’m able to use materials and apply my knowledge and skills to contribute to these fields.

4) What keywords would you use to describe your work?

Innovation; Discovering new things; Excitement; Passionate about inventions; Novelty factor.

5) What has been your career highlight?

The research that I do is incredibly important to me and it’s exciting to see how my work can make a difference in the world. It’s remarkable to see how my research ideas have been transformed from conception to demonstration and exploitation.

6) What’s the best piece of advice you’ve given others?

There are so many little sayings I enjoy sharing with others. Not only do I believe them, I also live by them daily: Failure is a medicine that one should use to improve; When one door shuts, another opens. When you lose one opportunity, you often find a different one; Life is a journey.

7) If you had a superpower, what would it be and why?

I would love to engineer a perfect surface solution with self-healing properties and the capability to harness energy from nature in an effortless and eco-friendly way – that would be amazing. And then I would develop new materials based on my research.

8) What do you do in your spare time?

I really enjoy getting involved in various charity projects. I would always like to do more for the community, but time is always a factor. I also enjoy spending time with my children.

9) What’s your favourite book at the moment?

Life Ascending: The Ten Great Inventions of Evolution by Nick Lane

10) Is there anything else you would like to share?

I would love the opportunity to collaborate with UCL colleagues across all disciplines and open up new areas of research leading to material discovery. If you are also interested in getting involved in something like this, please send me an email at k.choy@ucl.ac.uk

 

Professor Choy obtained her D.Phil. in Materials Science from the University of Oxford. Her D.Phil. thesis was on the Chemical Vapour Deposition of new ceramic protective coatings for SiC fibres reinforced Ti based metal matrix composites.

She currently leads a team of 12 researchers, performing pioneering research into novel, sustainable, and cost-effective processing of nanostructured materials, thin films and thick coatings using non-vacuum and environmentally friendly chemical vapour based deposition methods, with unique nanocrystalline microstructure and superior properties for structural, functional and biomedical applications.

She has over 25 years’ experience in surface coating and nanomaterials.

 

 

Vintage space: Venus in 1991

By Oli Usher, on 28 July 2015

On 5 May 1989, the Space Shuttle Atlantis released the Magellan probe into low Earth orbit.

A short while later, Magellan’s rockets fired, sending it towards the sun.

Magellan being deployed from the Space Shuttle Atlantis on 5 May 1990. Photo: NASA (public domain)

Magellan being deployed from the Space Shuttle Atlantis on 5 May 1989. Credit: NASA

Swinging around our star, it arrived at its destination 15 months later: the planet Venus.

Venus is in some respects the most Earth-like planet in the Solar System. It is a similar size to our planet, has a rocky surface and a thick cloudy atmosphere. However, it is much closer to the sun, and thanks to its atmosphere, experiences a powerful greenhouse effect.

The planet Venus, seen by Mariner 10. Credit: NASA (processing by Ricardo Nunes)

The planet Venus, seen by Mariner 10. Credit: NASA (processing by Ricardo Nunes)

Surface temperatures there are well over 400 degrees Celsius, atmospheric pressure is similar to what submersibles experience a kilometre down into Earth’s oceans, and the ‘air’ of Venus’ atmosphere is full of sulphuric acid.

Exploration of Venus’ surface has been in the form of brief snapshots, taken in the few tens of minutes that landers survive the harsh conditions there. All the landers so far have been Soviet; UCL has a number of their photos in its Centre for Planetary Sciences’ image archive (with a selection available online in high resolution).

The surface of Venus seen by the Venera 13 probe. Credit: UCL RPIF

The surface of Venus seen by the Venera 13 probe. Credit: UCL RPIF

Observing Venus from space is less challenging – and less rushed.

Between 1990 and 1994, Magellan was able to study the planet’s surface at leisure from its position high above the atmosphere. Because of the thick clouds, its images had to be produced by radar rather than optical photography, so they are not in colour. But they are extremely sharp.

Here is one of these images, held in UCL’s archives:

magellan-synthetic-aperture-radar

One of Magellan’s radar images of Venus’ surface. (The image is squint in the original!). Credit: UCL RPIF

Most of the highly processed images from Magellan are produced by multiple passes of the spacecraft over the planet’s surface, building up a complete image of the surface. This particular picture, however, is incomplete, revealing how Magellan’s images are put together. The black stripes show the gaps between the strips observed during different orbits of the planet.

Also in UCL’s archives are some of the planning documents NASA produced as part of the mission, including this full map of the planet’s surface:

magellan-planning-chart-cc

Planning chart for the Magellan mission. Click here for labelled image showing the location of the above radar map. Credit: UCL RPIF

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