Egos and intensity in the search for dark matter

Voices in the dark.

In the next few weeks, the world’s most sensitive dark matter detector will begin its operations under Italy’s Gran Sasso mountain. This seems a good time to point out that it is sharing the mountain with a detector that may already have found some. What a shame, then, that what might one day be viewed as a historic result has been mired in petty name-calling.

We’ve been looking for dark matter since 1933, when the astronomer Fritz Zwicky pointed out that clusters of galaxies move in ways that seemingly defy the laws of physics. The movement made sense only if the clusters were experiencing a gravitational pull from some invisible stuff nearby.

For various reasons, mostly to do with other astronomers not liking Zwicky very much, we’ve been searching for dark matter seriously only since the 1970s. During those four decades, there has been a series of pronouncements about its discovery being only a decade away. It might now be time to take those pronouncements a little more seriously: lately, the sensitivity of detectors has been improving tenfold every two years. We must surely be on the verge of finally nailing down the existence of dark matter. If we haven’t already, that is.

Dark matter doesn’t just hold gravity clusters together – it’s everywhere. It’s right here on earth, for instance: billions of dark matter particles fly through your body every second. You won’t feel them and they won’t harm you. They don’t interact much with the stuff of our everyday reality, which is what has made them so hard to detect.

While we don’t have any concrete detections of single particles, we do seem to have a discernible signal from passing through clouds of dark matter. It was first spotted by the DAMA dark matter detector, which is based, like the new DarkSide-50 detector, deep under the mountains at Gran Sasso. The rock covering them protects the instruments from distracting sources of noise.

In 2008, DAMA’s operators announced that they had identified a signal that rose and faded with the seasons. It might have been ignored, except that this is exactly what Katherine Freese predicted for a dark matter signal in 1986. She said that the intensity of dark matter detections should depend on the time of year, because as the earth whirls round the sun and the sun moves through the Milky Way, the amount of dark matter hitting the detectors will ebb and flow. It’s rather like the difference between walking into wind-driven rain, then turning and walking the other way. In June, dark matter hits Planet Earth full in the face; in December, it’s at our back.

So, it was pretty exciting that DAMA’s detector saw this predicted pattern. It was even more exciting when another detector, CoGeNT, based in a deep underground mine in Minnesota, also saw it. It’s a shame that a third detector, Xenon, didn’t.

Xenon is also in the Gran Sasso mine and there is no love lost between the leaders of these two research efforts. CoGeNT’s Juan Collar has called Xenon’s science “pure, weapons-grade balonium”. Not content with antagonising his peers, Collar has also accused the DAMA project of “cheapening the level of our discourse to truly imbecilic levels”.

Finding dark matter is proving to be astonishingly difficult and everyone knows there’s a Nobel prize at stake, so it’s not surprising that the claws are out.

Anyway, welcome to the fray, DarkSide-50; there is definitely room for more players in this competition. Whether there is room for more egos, however, is another matter.

Inside the DarkSide-50 experiment.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 18 February 2013 issue of the New Statesman, Iraq: ten years on

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The best Instagram accounts to follow if you love space

As new space findings hit the news on an almost daily basis, the app offers an alternative window onto the universe.

If there’s anything that can break us away from the humdrum monotony of modern life, it’s space. It renders us awe-struck and captures our imagination with its vastness and surreal imagery, and as astronomy-related research expands, cosmic mysteries continue to unfold.

Whether it’s the occurrence of rare celestial events, the discovery of exoplanets that could potentially harbour life, or the confirmation of gravitational waves that ripple through the space-time continuum, it seems that there are new findings propelled onto our newsfeeds daily.  

Yet one of the best ways of keeping up to date with the latest research and projects at the frontier of space is on Instagram, the social media platform. Here are some of the accounts you should be following to get the greatest insight into space:

1. SpaceX (@spacex)

The aerospace company SpaceX designs spacecrafts and reusable rockets in the hope that their technology can one day make human life multi-planetary. Spearheaded be CEO Elon Musk, the company has the lofty ambition of one day colonising Mars. Below is a spectacular image of the company’s Falcon 9 rocket in its first-stage entry:

 

Photographer unexpectedly captures Falcon 9 second stage burn and first stage entry @slowcountrylife

A photo posted by SpaceX (@spacex) on

 

2. International Space Station (@iss)

The International Space Station, a habitable satellite whirling around the Earth approximately 16 times per day in low orbit, has an Instagram feed displaying the equipment on board as well as stunning pictures of the Earth from a distance. Here’s a picture from the station 250 miles above earth depicting the Earth as an azure blue marble:

 

The blue of the #bahamas can't be mistaken, even from 250 miles above. #YearInSpace #nasa #space #spacestation : @stationcdrkelly

A photo posted by International Space Station (@iss) on

 

3. Tim Peake (@astro_timpeake)

Currently aboard the International Space Station is Tim Peake, a British astronaut. As he has carried out his work on Expedition 46/47 on the station, he has shared a range of photos of Earth that he has shot with his Nikon D4 from the vantage point of space, from reefs off the coast of Mozambique to the glint of sun highlighting Vancouver Island. Here we have a clear image of the Pacific “Ring of Fire”:

 

3/3: The Pacific ‘Ring of Fire’ clear to see amongst the volcanoes of Kamchatka, Russia

A photo posted by Tim Peake (@astro_timpeake) on

 

4. Scott Kelly (@stationcdrkelly)

Scott Kelly is an engineer and a retired American astronaut who recently spent a year commanding the International Space Station, travelling 143,846,525 miles around our globe in the process. A quick scroll through his profile will demonstrate just how profound his experience must have been at the shores of space, and includes a host of images of the aurora borealis:

 

#GoodMorning #aurora and the Pacific Northwest! #YearInSpace #northernlights #beautiful #morning #space #spacestation #iss

A photo posted by Scott Kelly (@stationcdrkelly) on

 

5. Nasa Goddard (@nasagoddard)

Nasa’s Goddard Space Flight Centre was the company’s very first flight centre. It’s the largest of its kind, and the official Instagram account for the centre serves as a highlight reel for everything NASA is working on. There are behind-the-scenes looks at the James Webb Space Telescope under construction, computer-simulated images of supermassive black holes, and clear views of distant galaxies captured by the Hubble Space Telescope:

 

Observations by the NASA/ESA Hubble Space Telescope have taken advantage of gravitational lensing to reveal the largest sample of the faintest and earliest known galaxies in the universe. Some of these galaxies formed just 600 million years after the big bang and are fainter than any other galaxy yet uncovered by Hubble. The team has determined for the first time with some confidence that these small galaxies were vital to creating the universe that we see today. An international team of astronomers, led by Hakim Atek of the Ecole Polytechnique Fédérale de Lausanne, Switzerland, has discovered over 250 tiny galaxies that existed only 600-900 million years after the big bang— one of the largest samples of dwarf galaxies yet to be discovered at these epochs. The light from these galaxies took over 12 billion years to reach the telescope, allowing the astronomers to look back in time when the universe was still very young. Although impressive, the number of galaxies found at this early epoch is not the team’s only remarkable breakthrough, as Johan Richard from the Observatoire de Lyon, France, points out. “The faintest galaxies detected in these Hubble observations are fainter than any other yet uncovered in the deepest Hubble observations.” By looking at the light coming from the galaxies the team discovered that the accumulated light emitted by these galaxies could have played a major role in one of the most mysterious periods of the universe’s early history — the epoch of reionization. Reionization started when the thick fog of hydrogen gas that cloaked the early universe began to clear. Ultraviolet light was now able to travel over larger distances without being blocked and thus the universe became transparent to ultraviolet light. Credit: NASA/ESA #nasagoddard #Hubble #HST #space #galaxy

A photo posted by NASA Goddard (@nasagoddard) on

 

6. Roscosmos (@roscosmosofficial)

Roscosmos is the Russian Federal Space Agency at the heart of all space endeavours in Russia. The agency is involved in the maintenance and progression of the International Space Station, and is working on its own research projects such as a planned robotic mission to one of Mars’s moons.  Here’s the launch of a rocket from the Vostochny Cosmodrome which is under construction:

 

7. Nasa (@nasa)

Over the years, Nasa has firmly committed to pushing the boundaries of space exploration, and, as its 12.3m Instagram acolytes would agree, it has been successful. As part of the Frontier Fields campaign investigating galaxy clusters, a recent deep field image from the Hubble revealed bounds of galaxies in the constellation of Leo:

 

Nearly as deep as the Hubble Ultra Deep Field, which contains approximately 10,000 galaxies, this incredible image from the Hubble Space Telescope reveals thousands of colorful galaxies in the constellation of Leo (The Lion). This vibrant view of the early universe was captured as part of the Frontier Fields campaign, which aims to investigate galaxy clusters in more detail than ever before, and to explore some of the most distant galaxies in the universe. Galaxy clusters are massive. They can have a tremendous impact on their surroundings, with their immense gravity warping and amplifying the light from more distant objects. This phenomenon, known as gravitational lensing, can help astronomers to see galaxies that would otherwise be too faint, aiding our hunt for residents of the primordial universe. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt #nasa #hubble #astronomy #science #space #galaxy #galaxies

A photo posted by NASA (@nasa) on