Ian O'Neill, Author at Universe Today

July 14, 2008December 24, 2015 by Ian O'Neill

Observing an Evaporating Extrasolar Planet

Artist impression of an evaporating planet orbiting a main sequence star (NASA)

Observations of planets orbiting other stars are becoming increasingly common as astronomical techniques become more and more sophisticated. But some extrasolar planets have a stronger than normal spectroscopic signature, often stronger than their optical signature. What could be causing this? In a recent study, observations of the extrasolar planet HD 209458b (also unofficially known as “Osiris”, which orbits a star in the constellation of Pegasus) revealed the strongest ever spectroscopic signature for a giant extrasolar planet, indicating Osiris is producing a huge cloud of gas. This gas is being lost from the planet’s atmosphere; Osiris is evaporating…

Osiris orbits a star (imaginatively) called HD 209458, a yellow dwarf not too dissimilar to our Sun (with 1.1 solar masses, 1.2 solar radii and a surface temperature of 6000 K). This extrasolar planet is special in that it is readily observable during its transit period of 3.5 terrestrial days. This very short year is due to its small orbital radius of only 0.047 AU. Osiris could be called a “hot Jupiter” as it is a gas giant, approximately 60% the mass of Jupiter and it orbits within 0.05 AU of its parent star. Because of its close proximity to HD 209458, Osiris has a surface temperature of over 1000 K.

Osiris’ size and compact orbit causes HD 209458’s luminosity to vary by 2% as the planet passes in front of the star. It is for this reason that HD 209458 has been designated as a “variable star” with the name V376 Pegasi.

However, spectroscopic analysis of the star show that emissions from elements such as neutral hydrogen and a carbon ion are dimmed far more than the 2% optical luminosity dimming. What could be causing this increase in dimming for spectroscopic emission lines? As light is produced by HD 209458, it is blocked by the Osiris planetary disk, creating the 2% dimming observed by optical instrumentation. However, something is increasing the disk cross section area, absorbing certain spectral wavelengths of stellar emission. For example, there is a 5-15% dimming effect on neutral hydrogen (H I at 121.6 nm) and a 7-13% dimming effect on both atomic oxygen (O I at 130.5 nm) and singly ionized carbon (C II at around 133.5 nm). This led astronomers to realize there was a cloud of gas surrounding Osiris, allowing most of the optical wavelengths to pass through, but absorbing some spectroscopic lines.

As Osiris is orbiting so close to its star, the X-ray and EUV emissions are exciting gases in the exosphere (the uppermost reaches of the gas giant’s atmosphere), causing heating and expansion. As the planet is strongly influenced by its star’s gravitational pull, tides will play a strong part in amplifying the expansion of Osiris’ atmosphere. At a certain point, when the planet’s “exobase” (or the base of the exosphere) reaches the Roche Limit, atmospheric gases will begin to escape the gravitational pull of the planet and the interaction with HD 209458 causes a geometrical blow-off, ejecting huge amounts of atmospheric gases into space. The atmosphere of Osiris is therefore evaporating.

This is an intriguing subject, and more details can be found in the review recently published by David Ehrenreich from the Laboratoire dâ€™astrophysique de Grenoble, Universite Joseph Fourier, France.

Source: arXiv:0807.1885v1 [astro-ph]

July 14, 2008December 24, 2015 by Ian O'Neill

Binary Asteroid Glides Past Earth

A rare event has given astronomers a great view of a binary asteroid system. Tonight, asteroid 2008 BT18 passed 1.4 million miles from Earth, shining like a 13th magnitude star. Before July 7th, astronomers believed 2008 BT18 was “just another” near-Earth asteroid, but then the Arecibo radio telescope obtained a “delay-Doppler” image of the asteroid and found it in fact had a binary partner. Although binaries are fairly common in the Solar System, this was a rare opportunity for a ground-based telescope to capture such a clear view…

Only last week, Nancy wrote about binary asteroids and double craters found on Earth may be evidence that our planet has been hit by binaries in the past. As the article was being written, the Arecibo radio telescope in Puerto Rico was taking a detailed look at a binary asteroid approaching Earth. Although asteroid 2008 BT18 posed no threat to Earth, astronomers are very keen to learn more about binary asteroids to understand how they form and how they may be deflected from a collision course with Earth should a binary get too close.

About 16% of asteroids in the Solar System are thought to be binaries, so this event was a great opportunity for Arecibo to image 2008 BT18 and it could be seen by amateur astronomers as a 13th magnitude star. The Arecibo observatory has discovered 53% of all near-Earth binaries, so this seasoned radio telescope is an important component in the observation of these objects.

The asteroid binary was fairly sizeable but passed about six times the Earth-Moon distance from us. “The sizes of the two components are 600m for the primary and >200m for the secondary,” said Lance Benner, a scientist from NASA’s Jet Propulsion Laboratory (JPL). “The primary looks spheroidal, but we don’t yet know about the shape of the secondary.”

Other telescopes are analyzing the binary orbit, asteroid masses and density of the two objects, such as NASA’s Goldstone radar in the Mojave Desert, California. Although Goldstone is smaller than Arecibo, there is a strong echo for scientists to analyze the data collected from the passage of the asteroid pair. According to spaceweather.com, observers in the Southern Hemisphere had the opportunity to see 2008 BT18 pass through the constellation of Canis Major, heading south.

Source: Spaceweather.com

July 12, 2008December 24, 2015 by Ian O'Neill

NASA Needs to Take Space Sex Seriously

The US space agency needs to have better consideration for the sexual needs of their astronauts during long missions in space. Also, more research needs to be done to investigate human embryo development in zero-gravity or low-gravity environments, especially if NASA is serious about setting up a colony on Mars in the next 30 years. These warnings have been issued by a NASA advisor at a time when the agency doesn’t have enough funds allocated for human space physiology. These concerns are by no means trivial, basic human needs and the ability to procreate beyond Earth may be critical for missions lasting years…

At a time when the question “Can we have sex in space?” is becoming more and more popular by the future space tourists hoping to become a member of the 100-mile high club, a serious issue is beginning to surface for our long-term presence in space. Humans have needs, and although the astronauts selected by NASA, ESA and the other international space agencies are highly professional individuals, Dr Jason Kring, a NASA advisor and assistant professor at Embry-Riddle Aeronautical University in Florida, has pointed out that sexual desire is as potent as the need for water and food. “But the bottom line is that, like hunger and thirst, sex is a basic biological motive,” he said in an interview with the UK’s Sunday Telegraph. “The potential round-trip mission to Mars could take three years. It doesnâ€™t make sense to assume that these men and women are going to have no thoughts of it for three years. Nasa and other space agencies should address this in their training and in crew selection.” Kring suggests our future long-term space explorers should replicate what the early polar explorers did and take a colleague as a lover to minimize sexual frustration.

It is difficult to predict the stresses long-term missions into space and to other planets may cause, but there is a very practical reason for this worry. Heightened stress on a spaceship will create an increased risk of confrontations, lack of focus and mission failure. When considering a possible 3-year mission to Mars, mission scientists will want the crew to be as calm and stress-free as possible.

Kring adds that future manned spacecraft to the Moon and Mars should be designed to optimize the privacy of astronauts so relationships can be consummated. This basic human need was recognized by explorers here on Earth where South Pole expedition members took on “expedition spouses” as sexual partners for the duration. When the expedition was over, the explorers would return home to their families and spouses. Pairing up with a colleague therefore sidesteps the biological issues of the possibility of “going without” for months, or years at a time. There are obvious questions surrounding the psychological effect of taking on “expedition spouses” (especially the effect on the partners waiting here on Earth for the astronauts return!), but the biological question will at least have an answer.

The fact remains however, that we are naive of the effects of sex in space, let alone if it is even a pleasurable experience. The mechanics of “human docking procedures” (as described by tests carried out by the Russian space agency) are a lot more complicated when in zero gravity. NASA researchers have pointed out that additional problems include motion sickness, increased sweating and a drop in blood pressure – all of which are big problems for astronauts in space.

There are also huge ethical questions hanging over possible pregnancies in space. Zero-G tests on rat embryos produced decreased skeletal and brain development, the effects on a human embryo will remain a mystery. Also, even if astronauts are having sex for purely recreational reasons, the effectiveness of oral contraception has been brought into question, making the whole procedure highly problematic, risking accidental pregnancies (something no space agency is prepared for, especially during missions to the Moon or Mars).

The fact remains that NASA continues to cut back biological research in favor of future Moon missions, so much about human sexuality in space will remain a mystery. This point is highlighted by a NASA spokesperson who stated, “We don’t study sexuality in space.”

Source: Sunday Telegraph

July 10, 2008December 24, 2015 by Ian O'Neill

Listen to Terra Chat Live Tonight: Cosmic Occurances, Planet X and Space Travel (Update)

Update: The Terra Chat show recording is now available online as an mp3 if you missed the live broadcast…

In a follow-up radio interview on Blog Talk Radio’s Terra Chat, I will be Colin Knight’s special guest to briefly discuss my recent Universe Today 2012 articles and then chat about my thoughts on space travel and Mars colonization. I previously appeared with Colin on June 8th to discuss the Mayan 2012 Prophecy, so I’m overjoyed to be invited back.

If you are interested and want to listen in to Colin Knight’s Terra Chat show, with me as his guest, go to the Blog Talk Radio: Terra Chat homepage and you’ll find the live radio feed.

Time: Thursday July 10th 2008, 10pm Eastern Time (7pm Pacific Time)

More information on tonight’s show Â»

I have another follow-up show on Paranormal Radio at the end of the month with Captain Jack, so I’ll keep you posted (listen to my previous appearance). Cheers, Ian

July 10, 2008December 24, 2015 by Ian O'Neill

Particle Physicists Discover Lowest Energy “Bottomonium” Particle

During particle collisions, hadrons split into quarks and bosons (University of Oregon)

Particle physicists working with the BaBar detector at Stanford Linear Accelerator Center have discovered a new particle in the bottomonium family of “quarkonium” particles. Technically it isn’t a “new particle” it is a previously unobserved state of particle, but when we are talking about subatomic particles, their energy states become a big deal (and their names get very cool). We are in the realms of the vanishingly small and the discovery of the lowest energy bottomonium particle may not seem very significant. But in the world of quantum chromodynamics, this completes the long quest to find experimental evidence for this elusive meson and may help explain why there is more matter than anti-matter in the Universe…

Quarkonia are types of mesons containing two quarks: one quark and its anti-quark (they are therefore “colourless”). They belong to one of two families: “bottomonium” or “charmonium”. As the names suggest, bottomonium contains a bottom quark and anti-bottom quark; charmonium contains a charm quark and anti-charm quark. Groups of three quarks (interacting via the strong force) are baryons (i.e. protons and neutrons) whereas groups of two quarks are mesons. Mesons are all thought to be made from a quark-antiquark pair and are therefore of huge importance when studying why there is more matter than anti-matter in the Universe.

This is where the BaBar detector at the Stanford Linear Accelerator Center (SLAC), CA, comes in. The BaBar international collaboration investigates the behaviour of particles and anti-particles during the production of the bottomonium meson (bottom-antibottom quark pairs) in the aim of explaining why there is an absence of anti-particles in everyday life.

For each particle of matter there exists an equivalent particle with opposite quantum characteristics, called an anti-particle. Particle and anti-particle pairs can be created by large accumulations of energy and, conversely, when a particle meets an anti-particle they annihilate with intense blasts of energy. At the time of the big-bang, the large accumulation of energy must have created an equal amount of particles and anti-particles. But in everyday life we do not encounter anti-particles. The question, therefore, is “What has happened to the anti-particles?” – From the BaBar/SLAC collaboration pages.

All matter has a “ground state”, or the lowest energy the system is trying to attain. As particles for instance try to reach this ground state, they lose energy, often in the form of electromagnetic radiation. Once reached, the ground state determines the baseline at which measurements can be made for higher energy states of those particles. And this is what the BaBar team has done, they have been able to isolate the lowest possible energy state for the bottomonium particle (which is far from easy). So what have they named the ground state of bottomonium? Quite simply: Î·b, pronounced “eta-sub-b“.

The bottomonium particle was generated during a collision between an electron and positron. The energy generated by this collision created a bottom quark and an anti-bottom quark bound together. At this point, the bottomonium particle was of too high an energy, but it very quickly decayed, emitting a gamma ray leaving the Î·b behind. However, Î·b’s are highly unstable and will quickly decay into other particles, plus they are very rare and difficult to detect. This particular decay event only occurs once in every two or three thousand higher energy bottomonium decays, so many collisions had to be measured and a huge amount of data had to be gathered by the BaBar detector before a precise measurement of the Î·b ground state could be gained.

“This very significant observation was made possible by the tremendous luminosity of the PEP-II accelerator and the great precision of the BaBar detector, which was so well calibrated over the BaBar experiment’s 8-plus years of operation. These results were highly sought after for over 30 years and will have an important impact on our understanding of the strong interactions.” – Hassan Jawahery, BaBar Spokesperson, University of Maryland.

If you want to find out more, you can check out the BaBar team’s publication (with the longest list of co-authors I’ve ever seen!) or the SLAC press release.

Source: SLAC

July 9, 2008December 24, 2015 by Ian O'Neill

Large Hadron Collider Could Generate Dark Matter

One of the biggest questions that occupy particle physicists and cosmologists alike is: what is dark matter? We know that a tiny fraction of the mass of the universe is the visible stuff we can see, but 23% of the Universe is made from stuff that we cannot see. The remaining mass is held in something called dark energy. But going back to the dark matter question, cosmologists believe their observations indicate the presence of darkmatter, and particle physicists believe the bulk of this matter could be held in quantum particles. This trail leads to the Large Hadron Collider (LHC) where the very small meets the very big, hopefully explaining what particles could be generated after harnessing the huge energies possible with the LHC…

The excitement is growing for the grand switch-on of the LHC later this summer. We’ve been following all the news releases, research possibilities and some of the more “out there” theories as to what the LHC is likely to discover, but my favourite bits of LHC news include the possibility of peering into other dimensions, creating wormholes, generating “unparticles” and micro-black holes. These articles are pretty extreme possibilities for the LHC, I suspect the daily running of the huge particle accelerator will be a little more mundane (although “mundane” in accelerator physics will still be pretty damn exciting!).

David Toback, professor at Texas A&M University in College Station, is very optimistic as to what discoveries the LHC will uncover. Toback and his team have written a model that uses data from the LHC to predict the quantity of dark matter left over after the Big Bang. After all, the collisions inside the LHC will momentarily recreate some of the conditions at the time of the birth of our Universe. If the Universe created dark matter over 14 billion years ago, then perhaps the LHC can do the same.

Should Toback’s team be correct in that the LHC can create dark matter, there will be valuable implications for both particle physics and cosmology. What’s more, quantum physicists will be a step closer to proving the validity of the supersymmetry model.

“If our results are correct we now know much better where to look for this dark matter particle at the LHC. We’ve used precision data from astronomy to calculate what it would look like at the LHC, and how quickly we should be able to discover and measure it. If we get the same answer, that would give us enormous confidence that the supersymmetry model is correct. If nature shows this, it would be remarkable.” – David Toback

So the hunt is on for dark matter production in the LHC… but what will we be looking for? After all dark matter is predicted to be non-interacting and, well, dark. The supersymmetry model predicts a possible dark matter particle called the neutralino. It is supposed to be a heavy, stable particle and should there be a way of detecting it, there could be the opportunity for Toback’s group to probe the nature of the neutralino not only in the detection chamber of the LHC, but the nature of the neutralino in the Universe.

“If this works out, we could do real, honest to goodness cosmology at the LHC. And we’d be able to use cosmology to make particle physics predictions.” – Toback

Source: Physorg.com

July 1, 2008December 24, 2015 by Ian O'Neill

“Almost Perfect” Samples are Scraped From Mars Surface For Analysis

The tranch called Snow White where the scrapes of ice and soil were extracted (NASA/UA)

With the Phoenix Mars lander in full science-operation-swing, the robotic arm has just scraped an “almost perfect” mix of regolith and water ice for its next analysis. Using a blade on the scoop, the robotic arm carried out 50 scraping actions across the bottom of the enlarged “Snow White” trench that was excavated on June 17th (22 sols since Phoenix touched down). Today, on Sol 33 of the mission, Phoenix has been preparing little mounds of dirt ready to be scooped up and dropped into the Thermal and Evolved-Gas Analyzer (TEGA) so the constituent minerals and water can be analysed. Besides, Phoenix has just built the first ever mini-sand castles on the Martian surface!

On Sol 24 of the mission, only 24 sols after it landed on Mars, Phoenix found the first evidence of water ice on the Martian surface. Pictures taken four sols apart showed a white substance had sublimed into the tenuous Martian atmosphere at about the correct rate for water ice under those conditions. This was after a bumpy start when the clumpy regolith didn’t make it past the TEGA screen in a preliminary oven experiment. Then last week, Phoenix carried out a preliminary “wet-lab” test with the Microscopy, Electrochemistry and Conductivity Analyzer (MECA) instrument and found the mix of minerals in the Mars regolith and its pH levels had a striking resemblance with soils commonly found here on Earth. With all these groundbreaking discoveries mounting up, what can we expect next?

Well, today’s announcement suggests the next step is to thoroughly prepare small piles of samples scraped from the bottom of a trench called “Snow White” dug on Sol 22. Once this is complete, each sample (containing approximately two to four teaspoonfuls) can then be sprinkled into the TEGA instrument so thorough analysis can take place. The bottom of Snow White appears to be rich in water ice, so the scraping action will have created small particles of regolith and small ice crystals. Having encountered the clumpiness of regolith before, the mission scientists are keen to push ahead with some flawless experiments.

Having overviewed the small samples, agreeing that the piles were “almost perfect samples of the interface of ice and soil,” Phoenix has been sent commands to scoop up each pile of dirt and sprinkle them into the TEGA. The instrument will then bake and analyse the soil to assess its volatile ingredients, like water. The melting point of the water ice can also be assessed. Once the data has been transmitted back to Earth scientists can begin to study the constituents of the sub-surface regolith, gaining a detailed look into just how hospitable the Red Planet could be.

Keep making those little sand castles Phoenix, we’re watching you very closely…

Source: Phoenix (University of Arizona)

July 1, 2008December 24, 2015 by Ian O'Neill

President Sarkozy and the French (Space) Revolution (Updated)

France hosts Europe's spaceport at Kourou, French Guiana (ESA)

It seems to be the week for big politics and space exploration. Yesterday, the Universe Today reported that Buzz Aldrin was worried about the future of the politically-driven US space policy; he is currently lobbying US President hopefuls Barack Obama and John McCain to increase NASA funding. On the other side of the pond, French President Nicolas Sarkozy also wants NASA’s European counterpart, ESA, to do better. However, Sarkozy wants to change the face of the ESA into the NASA model by making it politically driven, rather than leaving European bureaucrats to decide ESA priorities. ESA has operated independently from political pressures that often weigh down on space agencies, but Sarkozy is a huge advocate of the US system and believes space exploration should be politically motivated. This is bound to raise a few eyebrows, as the very agency he is promoting is facing some serious political uncertainty…

Update: Thanks to a couple of our readers from France, it has been pointed out that French astronauts are known as spationautes by the nation’s Centre National d’Ã‰tudes Spatiales (the French space agency). I have corrected the mini-discussion at the bottom of this article, reflecting this fact. Thank you Julien and Alexis!

In the 1960’s NASA’s motivation to land a man on the Moon was politically motivated, but in 1986, the UK Prime Minister Margaret Thatcher’s decision to pull Britain out of Europe’s manned space program was also politically motivated. Politics and space exploration can go hand-in-hand, but it can also hinder a nation’s development as space policy can be overturned depending who is in office. Worries to one side, President Nicolas Sarkozy believes that France may begin a revolution in the ESA’s outlook for the future. Amidst concerns aired by established space agencies that new space-faring nations like Japan, China and India may overtake Europe’s space agency, Sarkozy has announced radical plans for an accelerated effort for a politically driven push to send man back to the Moon and then to Mars.

Until now, ESA has maintained a more scientific approach to space exploration, but Sarkozy believes this approach has caused ESA to miss opportunities, possibly making Europe redundant in the future of space travel:

“The United States, Russia, China and Japan would not do what they do in space without a political motivation; Europe has only had a scientific motivation until now. So what we are saying is, let’s get the same chances as the others. Beside the scientific pilot, let us have a political pilot, too, which will be the EU, because there is only the EU that can speak at that level.” – President Sarkozy.

Although this is a bold statement, critics of Sarkozy’s stance point out that the comparison between NASA and ESA is not realistic. After all, NASA spends eight times more on space development than ESA, so Europe would need to allocate huge resources if there were to be a new political direction in ESA science. The 33-year old space agency is run by 17 member-states within the European Union (plus Switzerland, Norway and Canada) so Sarkozy’s aspirations may face setbacks, but the fact remains that France spearheads much of ESA’s operations so the French President’s views will not be ignored.

This is reflected in documents reviewed by the BBC that the French plans for an ESA overhaul are at an advanced stage. Key members of ESA have said that to become a space exploration powerhouse, they need to develop their own means to get European astronauts into space (a task that ESA have had to depend on the US and Russia till now). ESA have developed their own launch site in French Guiana (a major access to space for commercial satellites), have been heavily involved with the International Space Station, developed some of the most advanced robotics to be sent into space (i.e. the Automated Transfer Vehicle) and is currently developing the controversial European global positioning satellite system, Galileo. All is needed is an increase in funding so ESA can push toward manned missions to the Moon and Mars. Perhaps in this case, a politically orientated space agency may be a step in the right direction… until President Sarkozy’s term ends in any case…

Aside: A cosmonaut is a Russian astronaut, a taikonaut is a Chinese astronaut, but what is a French astronaut called? Well, the prefixes “astro-“, “cosmo-” and “taiko-” are pretty much equivolent. So what’s the French for “astro”? Well, “astro” actually… so a French astronaut is called an astronaut (or astronaute). I’m glad I cleared that up…

Update (July 3rd): Actually, the official designated name for a French astronaut is spationaute (according to the Centre National d’Ã‰tudes Spatiales). Thank you to our eagle-eyed French readers for sending me the tip! Now we have astronaut (US), cosmonaut (Russia), taikonaut (China) and spationaute (France). You learn something new every day!

Source: BBC

June 30, 2008December 24, 2015 by Ian O'Neill

Aldrin Warns that NASA will fall Behind Russia and China in Space Exploration

Buzz Aldrin and the US flag during NASAs biggest achievement - man on the Moon (NASA)

The world knows the huge potential China and Russia have for space exploration. Russia is maintaining a strong presence in space with their sturdy Soyuz program and China has set its sights on having their very first “taikonaut” EVA at the end of this year. But where does this leave NASA? The US space agency has spearheaded the exploration of space for the last 50 years, but amongst all the talk about NASA setbacks, overspending and delays, could the glory days be coming to an abrupt end? In May, the legendary astronaut John Glenn spoke out against Shuttle decommissioning and last week, US Senator Bill Nelson called a meeting at Cape Canaveral to raise concerns about announced job cuts in 2010. Now, the most famous NASA ex-employee and second man on the Moon, Buzz Aldrin has voiced warnings that the US could lose its grip on space and begin to be left behind by Russia and China…

On July 20th, 1969, the Apollo 11 Lunar Module Pilot waited for Neil Armstrong to make the first footprint in the lunar dust. Soon after, Buzz Aldrin joined Armstrong on this momentous step and making world history, setting the world alight with optimism that man was just about to embark on the next phase of evolution: leaving Earth and exploring the stars. Unfortunately this dream was only realised for three years (until 1972) after six successful lunar landings (Apollo 11, 12, 14, 15, 16 and 17), and to this day the Apollo 17 mission touch-down (December 15th, 1972) remains the last time we landed on the Moon.

Although we may not have revisited our natural satellite for the best part of four decades, we have been busy with our focus on the robotic exploration of the Solar System. But work has started on the Shuttle replacement, the Constellation Program, with the promise of sending man back to the Moon by 2020 and then Mars soon after, can we begin to get excited that NASA is gaining momentum for the next “giant leap for mankind?”

Many prominent figures are now worried that the light is beginning to dim for the future of NASA. NASA prides itself on developing new technologies, spearheading the push into space, but what happens when the funding dries up and other nations pick up where they left off? One voice that cannot be ignored is that of Buzz Aldrin who has voiced his grave concern that NASA, and indeed the USA, risks falling behind China and Russia in the “space race” if efforts were not redoubled by future US governments. With the US presidential elections looming, Aldrin has vowed to lobby both Barack Obama and John McCain to “retain the vision for space exploration,” not only to maintain, but increase NASA funding.

During an interview with the UK’s Sunday Telegraph newspaper he said, “If we turn our backs on the vision again, we’re going to have to live in a secondary position in human space flight for the rest of the century.” And he is not alone with this concern. Both fellow retired astronaut John Glenn and US Senator Bill Nelson have recently spoken out about their concerns for NASA’s future, ensuring the space exploration debate will remain alive over the coming months.

Although Russia has a long and proud history in human space flight, the Chinese are showing their thirst for a big push into space, with a manned mission to the Moon on the cards. “All the Chinese have to do is fly around the Moon and back, and they’ll appear to have won the return to the Moon with humans. They could put one person on the surface of the Moon for one day and he’d be a national hero,” Aldrin added. Plus, Russia’s Soyuz program could be extended for manned missions beyond Earth orbit he pointed out.

There is a real worry in NASA that the US could lose its foothold in the leadership of space exploration, so it is hoped big voices within the ranks of legendary astronauts might begin to get the future government thinking about how important space exploration is to the US.

Source: Telegraph.co.uk

June 30, 2008December 24, 2015 by Ian O'Neill

Forget Neutron Stars, Quark Stars Might be the Densest Bodies in the Universe

The difference between a neutron star and a quark star (Chandra)

So neutron stars may not be the densest exotic objects in the cosmos after all. Recent observations of ultra-luminous supernovae suggest that these explosions may create an even more exotic remnant. Neutron stars can form after a star ends its life; measuring only 16 km across, these small but massive objects (one and a half times the mass of the Sun) may become too big for the structure of neutrons to hold it together. What happens if the structures of the neutrons inside a neutron star collapse? Quark stars (a.k.a. “Strange” stars) may be the result, smaller and denser than neutron stars, possibly explaining some abnormally bright supernovae observed recently…

Three very luminous supernovae have been observed and Canadian researchers are hot on the trail as to what may have caused them. These huge explosions occur at the point when a massive star dies, leaving a neutron star or black hole in their wake. Neutron stars are composed of neutron-degenerate matter and will often be observed as rapidly spinning pulsars emitting radio waves and X-rays. If the star was massive enough, a black hole might be formed after the detonation, but is there a phase between the mass of a neutron star and a black hole?

It appears there might be a smaller, more massive star on the block, a star composed not of hadrons (i.e. neutrons), but of the stuff that makes up hadrons: quarks. They are thought to be one step up the star-mass ladder, the point at which the mass of the supernova remnant is slightly too big to be a neutron star, but too small to form a black hole. They are composed of ultra-dense quark matter, and as neutrons break down it is thought some of their “up” and “down” quarks are converted into “strange” quarks, forming a state known as “strange matter.” It is for this reason that these compact objects are also known as strange stars.

Quark stars may be hypothetical objects, but the evidence is stacking up for their existence. For example, supernovae SN2005gj, SN2006gy and SN2005ap are all approximately 100 times brighter than the “standard model” for supernova explosions, leading the Canadian team to model what would happen if a heavy neutron star were to become unstable, crushing the neutrons into a soup of strange matter. Although these supernovae may have formed neutron stars, they became unstable and collapsed again, releasing vast amounts of energy from the hadron bonds creating a “Quark-Nova”, converting the oversized neutron star into a quark star.

If quark stars are behind these ultra-luminous supernovae, they may be viewed as super-sized hadrons, not held together by the nuclear strong force, but by gravity. Now there’s a thought!

Source: NSF