Posts by: Hamish Johnston

What can cosmic rays tell us about dark matter?

The positron excess as seen by AMS

Alive and well: the positron excess as seen by the AMS. (Courtesy: CERN)

By Hamish Johnston

Cosmic rays, dark matter and other astrophysical mysteries are being debated with much vigour at a three-day conference that began this morning at CERN in Geneva. Called “AMS Days at CERN”, the meeting will include presentations of the latest results from the Alpha Magnetic Spectrometer (AMS).

Located on the International Space Station, the AMS measures the energy of high-energy charged particles from the cosmos – otherwise known as cosmic rays. These particles are of great interest because they offer us a window into some of the most violent processes in the universe. Some cosmic rays have probably been accelerated during supernova explosions while others could be produced as matter is sucked into the supermassive black holes that lie at the centres of many galaxies.

(more…)

Posted in General | Tagged , , | 3 Comments | Permalink
View all posts by this author  | View this author's profile

Night visions, the sky 10 billion years ago and unexplained sounds from around the world

View from an Earth-like planet 10 million years ago

Good old days: the view from an Earth-like planet 10 billion years ago. (Courtesy: NASA/ESA/Z Levay (STScI))

By Hamish Johnston

This week’s Red Folder is inspired by a vision I had last night while I was putting out the garbage bins. I happened to look up at the sky just as the International Space Station (ISS) was travelling over Bristol. It was a very bright and impressive sight as it zipped overhead before disappearing at the eastern horizon. If you happen to be on an arc through northern Europe between Penzance and Poznań, you should also have a great view of the ISS this evening; you can find out when and where to look at the ISS Astroviewer website.

The ISS is one thing that you would definitely not see if you could look at the sky as it was 10 billion years ago – but have you ever wondered what that view would be? Zolt Levay at the Hubble Heritage Information Center has, and the above image is his vision of what the sky would look like from a hypothetical planet within a Milky Way-like galaxy 10 billion years ago. The work was inspired by a new collection of nearly 2000 images of galaxies as they appeared at that time in the history of the universe. Taken by a number of different telescopes including Hubble, “the new census provides the most complete picture yet of how galaxies like the Milky Way grew over the past 10 billion years into today’s majestic spiral galaxies”, according to NASA.

(more…)

Posted in The Red Folder | Tagged , , | 1 Comment | Permalink
View all posts by this author  | View this author's profile

Where is the coldest experiment on Earth?

Image of a refocused cloud of rubidium atoms

Chilly peak: a refocused cloud of rubidium atoms. (Courtesy: Tim Kovachy et al./Physical Review Letters)

By Hamish Johnston

California might be suffering a punishing drought, but a tiny corner of the Golden State is now the coldest place on Earth. This tiny super-cold patch was created at Stanford University by Mark Kasevich and colleagues, who have used “matter-wave lensing” to cool a cloud of about 100,000 rubidium atoms to less than 50 pK. That is just 50 × 10–12 degrees kelvin above absolute zero.

The temperature of a cloud of atoms is defined by the average velocity of the atoms as they drift about. Kasevich’s team used a series of lenses to reduce this average motion to less than 70 µm/s, which corresponds to 50 pK. This shatters the previous record of 1 nK for matter-wave lensing and represents “record-low kinetic temperatures” according to Physical Review Letters, where the research is described.

(more…)

Posted in General | Tagged | 5 Comments | Permalink
View all posts by this author  | View this author's profile

Protons return to the Large Hadron Collider

Aerial view of the LHC

Up and running: The first proton beams have been injected into the LHC in preparation for its second run. (Courtesy: Maximilien Brice/CERN)

By Hamish Johnston

The first proton beams of the second run of the Large Hadron Collider (LHC) were circulated earlier today. Travelling in opposite directions around the collider at CERN in Geneva, each beam was injected at 450 GeV. If all goes well over the next few days, the energy of each beam will be increased to the operating energy of 6.5 TeV.

(more…)

Posted in General | Tagged | 3 Comments | Permalink
View all posts by this author  | View this author's profile

Florida’s declining Space Coast, naming mountains on Pluto and silly rock bands

 

Artist's impression of Pluto

Name game: does that crater look like a Steve, or maybe a Carol? (Courtesy: IAU/L Calçada)

By Hamish Johnston

When I was a young lad back in the late 1960s, my family would join the annual March migration of Canadians to Florida. Along with alligator farms and the endless beaches, the Kennedy Space Center was a popular tourist destination and I can still remember visiting it and getting a solar spinner globe as a souvenir. Sadly, since the end of the Space Shuttle programme in 2011, Florida’s “Space Coast” has fallen on hard times. While there are still rocket launches – there are two planned for April – thousands of NASA employees have been let go and the surrounding communities look worse for wear. The New York-based photographer Rob Stephenson has put together a collection of images taken in and around the centre that he calls “Myths of the Near Future”. To me the photographs evoke the allure of the space age as well as the inevitable decline of any human endeavour.

(more…)

Posted in The Red Folder | Tagged , , | 2 Comments | Permalink
View all posts by this author  | View this author's profile

Electrical fault delays LHC start-up

Back down the tunnel: technicians will soon be repairing an electrical fault somewhere along the LHC (Courtesy: CERN/Maximilien Brice)

Back down the tunnel: technicians will soon be repairing an electrical fault somewhere along the LHC. (Courtesy: CERN/Maximilien Brice)

By Hamish Johnston

Today I was planning to write a cheerful blog celebrating the first circulating proton beams in the Large Hadron Collider (LHC), but sadly the particle gods are not smiling down on CERN this week. Accelerator physicists in Geneva have identified an electrical fault in one of the collider’s magnet circuits and plans to restart the giant machine this week have been put on hold – possibly for several weeks.

(more…)

Posted in General | Tagged , | Leave a comment | Permalink
View all posts by this author  | View this author's profile

Partial eclipse, meteorites and northern lights enthral a nation

Spot on: this photograph of the Sun taken during the eclipse clearly shows a sunspot (Courtesy: David Bloomfield)

Spot on: this photograph of the Sun taken during today’s eclipse clearly shows a sunspot. (Courtesy: David Bloomfield)

By Hamish Johnston

Earlier today millions of people in north-western Europe had the opportunity to see a partial eclipse of the Sun – or a total eclipse for the lucky few in northern Norway and the Faroe Islands.  Although it was a bit hazy here in Bristol, we were treated to spectacular views of the Moon covering 87% of the Sun. We have put up a Flickr album of images taken by colleagues here at IOP Publishing including the amazing photo above. It was taken by David Bloomfield and clearly shows a sunspot in the upper-left portion of the Sun.

(more…)

Posted in The Red Folder | Tagged , , , | Leave a comment | Permalink
View all posts by this author  | View this author's profile

Physics mosh pit, stained-glass scientists, opera and dance at CERN and more

 

By Hamish Johnston

Last week Physics World’s Michael Banks was at the APS March Meeting in San Antonio, and at the top of his to-do list was to belt out a few tunes at the event’s regular physics singalong. You can hear him in harmony with a roomful of physicists in a rendition of “(You Got Me) Lasing” in the video above. It is sung by Walter Smith of Haverford College to the tune of Britney Spears’ “(You Drive Me) Crazy” and his performance drives the dance floor into a frenzy of moshing physicists.

(more…)

Posted in The Red Folder | Tagged , | 2 Comments | Permalink
View all posts by this author  | View this author's profile

Pioneering women of physics, why you should become a particle physicist and a BICEP2 scientist on all that dust

Photograph of particle physicist at CERN

Smiley happy people: who would not want to be a particle physicist? (Courtesy: ATLAS)

By Hamish Johnston

Over on the Quantum Diaries blog, Aidan Randle-Conde has put together a lovely photo-essay called “30 reasons why you shouldn’t be a particle physicist”. It is reverse psychology, of course, and the 30 images highlight the benefits of devoting your life to studying sub-atomic particles. As someone who chose to do condensed-matter physics, do I now think that I made a huge mistake? No, but I have shared the thrill and excitement of being at CERN when the Higg’s was discovered and seen the Large Hadron Collider and its detectors up close, so I know where he is coming from.

(more…)

Posted in The Red Folder | Tagged , , | 8 Comments | Permalink
View all posts by this author  | View this author's profile

A journal for brief ideas, Heisenberg’s mirror, space-mission stickers and more

Mission accomplished: these graphics were created by Ariel Waldman and Lisa Ballard. (Courtesy: spaceprobe.es)

Mission accomplished: these graphics were created by Ariel Waldman and Lisa Ballard. (Courtesy: spaceprob.es)

By Hamish Johnston

Dr Heisenberg’s Magic Mirror of Uncertainty” is the name of a series of photographs taken in 1999 by the American photographer Duane Michals. The picture over at that link is lovely, but I don’t really see the connection to quantum mechanics. I suspect my artist friends would accuse me of being a scientific literalist, which doesn’t bother me one bit.

More to my liking are the graphics pictured above, which have been created by Ariel Waldman and Lisa Ballard. The pair run a website called spaceprob.es, which “catalogues the active human-made machines that freckle our solar system and dot our galaxy”. Here is their page on Voyager 2, which is packed with facts about the mission’s instruments and many accomplishments. These and other illustrations of space missions can be bought as stickers and posters – the perfect gift for the space enthusiast in your life.

(more…)

Posted in The Red Folder | Tagged , , , , | 2 Comments | Permalink
View all posts by this author  | View this author's profile