Category: Science

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Is dark matter hiding in plain sight?

In this article published on Skymania, Kulvinder Singh writes about  a study published in January of this year: Jiaxin Han, Carlos Frenk and others in China, the UK and Germany saw something unusual:

Three galaxy clusters—Virgo, Fornax and Coma, showed an excess of high-energy gamma-rays that couldn’t be accounted for from sources such as pulsars, gamma-ray bursts or background emissions – including from within our own Galaxy.

Something else seemed to be emitting radiation; something that continued three degrees out from the clusters (around six times the diameter of the full moon on the sky). However, they couldn’t be sure if the neutralino or some other effect was responsible.

The problem is that dark matter, save for its gravitational effect on radiation and normal matter (the type that makes up stars, galaxies, planets, nebulae, etc.), has never revealed itself. It’s a field of intense study in astrophysics as it accounts for 83-per cent of all the matter in the Universe – forming the nucleation sites of galaxies and creating the large-scale cosmic structure that we see.

Then it becomes very interesting:

This ‘lumpiness’ favours cold dark matter theories as warm dark matter would be too energetic to coalesce. The neutralino, a ‘supersymmetric’ particle is the favoured candidate. It is its own antiparticle so self-annihilations should produce gamma-rays of between 10—10,000Gev.

Now a team from New Zealand think that what they have spotted could indeed be neutralino annihilations, but they also sound a note of caution. Oscar Macías-Ramírez and his team from Canterbury University, Christchurch, used simulations from a study called the Phoenix Project* to model galaxy cluster Dark Matter halos and subhalos. They looked at the previous study by Han, Frank et al which had a strong (but not conclusive) claim to detecting neutralino annihilations. This weakened when cosmic ray contributions were added.

 This could be an explanation. Read the rest of the article here.

Galaxy Cluster Abell 1689 / HST ACS WFCH. Ford (JHU)

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Mars rover Curiosity landing: be ready!

 NASA announced news activities for Mars landing which started on August 2.

The series of news briefings from NASA’s Jet Propulsion Laboratory in Pasadena, California, will give you all the information you need on the upcoming landing of NASA’s Curiosity rover on Mars. The landing is scheduled for August 5.

Goals and objectives (from Wikipedia):

Cruise stage configuration of MSLThe MSL mission has four scientific goals: Determine the landing site’s habitability including the role of water, the study of the climate and the geology of Mars. It is also useful preparation for a future manned mission to Mars.

To contribute to these goals, MSL has six main scientific objectives:

1.Determine the mineralogical composition of the Martian surface and near-surface geological materials.
2.Attempt to detect chemical building blocks of life (biosignatures).
3.Interpret the processes that have formed and modified rocks and soils.
4.Assess long-timescale (i.e., 4-billion-year) Martian atmospheric evolution processes.
5.Determine present state, distribution, and cycling of water and carbon dioxide.
6.Characterize the broad spectrum of surface radiation, including galactic radiation, cosmic radiation, solar proton events and secondary neutrons.

As part of its exploration, it also measured the radiation exposure in the interior of the spacecraft as it traveled to Mars, and it is continuing radiation measurements as it explores the surface of Mars. This data would be important for a future manned mission.

Now we hope Curiosity rover will land successfully and bring some interesting data from Mars!

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On board the Mars Reconnaissance Orbiter

Universe Today knows how to catch my attention: Latest from Mars: Massive Polar Ice Cliffs, Northern Dunes, Gullied Craters. The HiRISE scientists monitor these regions to help in understand the climatic record stored in the ice sheet itself.

Several gorgeous images are in this week’s update from the HiRISE camera on board the Mars Reconnaissance Orbiter. This lovely image shows the cliffs at the edges of huge ice sheet at the North Pole of Mars. These cliffs are about 800 meters (2,600 feet) high, and the ice sheet is several kilometers thick at its center. This is a great spot to look for ice avalanches that HiRISE has captured previously.

The HiRISE team said that the slopes of these cliffs are almost vertical, plus dense networks of cracks cover the icy cliff faces making it easier for material to break free. The team regularly monitors sites like this to check for new blocks that have fallen. You can look for yourself to see if any avalanches have occurred since the last image was taken of this area, almost exactly one Martian year ago.

Go to the HiRISE website to see all the amazing images from Mars!

Below: Light-Toned and Possible Hydrated Materials in Gullied Crater.

Light-Toned and Possible Hydrated Materials in Gullied Crater
This observation shows a gullied crater in the Southern mid-latitudes with light-toned deposits near the center of its floor.
NASA/JPL/University of Arizona

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Stephen Hawking trials device that reads his mind

Stephen Hawking has a motor neurone disease related to amyotrophic lateral sclerosis, a condition that has progressed over the years.

He currently communicates using a series of cheek twitches to select words from a screen. “It is a very, very slow process,” says Philip Low at Stanford University in California, who is founder of healthcare company NeuroVigil. More from the article on New Scientist:

As Hawking loses control of his cheek, Low hopes he might instead communicate using his company’s portable device. The iBrain records brain activity from a single point on the scalp. An algorithm then extracts useful information from this activity.

In a preliminary trial, Low’s team asked Hawking to imagine moving his hands and feet while wearing the device. They were able to identify what movement he was imagining through changes in his brain activity.

Survival for more than 10 years after ALS diagnosis is uncommon. Stephen Hawking is an amazing scientist and a figther. Let’s hope this new portable device will let him ‘talk’ again…

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A keynote lecture by Professor Peter Higgs

Everyone now knows about the Higgs boson. If you want to know more about the scientist who gave the boson its name, then you have to watch tomorrow’s keynote lecture by Professor Peter Higgs.

More than 100 scientists from around the globe are gathering at Swansea University this July, for the 10th International Conference on Strong and ElectroWeak Matter (SEWM2012).

One of the highlights is a keynote lecture by Professor Peter Higgs of Edinburgh University, after whom the famously elusive Higgs boson is named.  Professor Higgs is also an Honorary Fellow of Swansea University.

Peter Higgs’ appearance at Swansea comes in the wake of exciting announcements from the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) about the discovery of the Higgs boson.

LIVE STREAM: Thursday 12th July, 4-5pm

More information on this page. I will be connected, I hope you will connect too!

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Higgs boson may be a reality!

So exciting! This morning I’ve read the news everywhere on the Internet:

The ATLAS and CMS experiments at CERN today presented their latest results in the search for the long-sought Higgs boson. Both experiments see strong indications for the presence of a new particle, which could be the Higgs boson, in the mass region around 126 gigaelectronvolts (GeV).

Can you imagine how it would change our understanding of the Universe? Amazing!

You can visit CERN website and for the non-specialists, read this article. You can also read Max Dana’s post about it, she is even more excited than me about the Higgs boson!

A proton-proton collision event in the CMS experiment producing two high-energy photons (red towers).
This is what we would expect to see from the decay of a Higgs boson
but it is also consistent with background Standard Model physics processes. © CERN 2012

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SETIcon II, June 22 -24, 2012 in Santa Clara, California

SETIcon (June 22 -24, 2012) is organized by the SETI Institute and it is a public event where science and imagination meet.

I wish I could attend SETIcon II but unfortunately and as you probably know, I’m not on Earth right now and I still don’t know yet how to teleport or travel through time…

But since you obviously are on Earth, maybe some of you living near Santa Clara, California, will attend the great event.

SETIcon brings together innovative scientists, science fiction authors, space and science artists, space lovers, and the curious and adventurous everywhere for a 3-day public celebration and exploration of space, real science, technology, imagination, and science education.

There is no other event in the world like SETIcon that explores space and the human imagination through the lens of real science, attracting global interest and participation. This is not a science conference with technical lectures (SETI Institute scientists lecture all over the world).

Instead we’ll bring together scientists with authors and artists to celebrate science and exchange ideas around space exploration and our place in the cosmos. SETIcon will create a new channel of discussion between Earthlings where real science and imagination will meet.

Note that SETIcon is also about music: Sheldon Reynolds, a star of the band Earth, Wind and Fire, will perform his hit, “Shining Star,” for Jill Tarter’s Gala on Saturday, June 23rd.

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Neutrinos can’t beat speed of light

It is now official: neutrino researchers admit Albert Einstein was right.

Mark Brown, Wired UK, writes:

Back in September 2011, a team of particle physicists detected neutrinos moving faster than the speed of light as they traveled from CERN to the Gran Sasso lab. They smashed the universal speed limit by 60 nanoseconds — a result that was constant, even after 15,000 repetitions of the process. The results seem to run counter to a century’s worth of physics and would overturn Einsten’s special theory of relativity if true. As such, CERN called for more experiments to double-check the findings.

[…] At the International Conference on Neutrino Physics and Astrophysics in Kyoto on June 8, CERN research director Sergio Bertolucci presented results on the travel time of neutrinos from CERN to the INFN Gran Sasso Laboratory, on behalf of four experiments — Borexino, Icarus, LVD and Opera. All four experiments measured a neutrino time of flight that was below the speed of light, confirming that neutrinos respect Einstein’s cosmic speed limit. The previous anomaly was “attributed to a faulty element of the experiment’s fibreoptic timing system.”

If you don’t get why it would have been a big deal to prove Einstein’s theory wrong, a news on The Guardian explains it all:

Travelling faster than the speed of light goes against Albert Einstein’s theory of special relativity. If it were possible, it would open up the troubling possibility of being able to send information back in time, blurring the line between past and present and wreaking havoc with the fundamental principle of cause and effect.

 Now we know where we stand.

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The 2012 Transit of Venus

I was in orbit around Earth and I could observe the 2012 transit of Venus. The planet Venus appeared as a small, dark disk moving across the face of the Sun, and the transit won’t be repeated until the year… 2117.

The transit of Venus is an old story, as described on the NASA website:

There is some evidence that the ancient Babylonians saw and recorded on a tablet something about Venus and the Sun in the 16th Century B.C., but the record is not clear. It is fair to say though that Galileo Galilee with his telescope, in 1610, was the first human to actually see Venus as more than just a bright point of light in the sky.

Johannes Kepler, meanwhile, was shaking up the world with his meticulous use of astronomical data assembled by Tycho Brahe. He predicted that Venus would pass in front of the Sun on December 6, 1631, but unfortunately the transit was not visible from Europe at all.

The first recorded sighting of this transit was by British cleric, Jeremiah Horrocks, and his friend William Crabtree, on December 4, 1639—only because Horrocks had mathematically predicted it, using better data than Kepler did.

I told you, it all started a long time ago… Now the best view of the transit of Venus, from Hong Kong, China.

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Dark matter finds new home in old gold mine

Lead is a town of about 3,100 residents, about a half-hour from the Wyoming border. Nestled nearly 5,000 feet beneath the earth, is a laboratory that could help scientists answer some pretty heavy questions about life, its origins and the universe.

Yes, we’re talking about dark matter. Regular matter — people and planets, for example — make up about 4 percent of the total mass-energy of the universe, he said. Dark matter makes up about 25 percent.

Dark matter is too sensitive to detect in normal laboratories, but one so far underground would help shield it from pesky cosmic radiation. Also, the LUX detector (Large Underground Xenon, the world’s most sensitive dark-matter detector) is submerged in water, further insulating it.

The article published on the Herald Tribune provides more details about this experience which could lead to unexpected results!