Space and astronomy news
Have you ever wondered what it takes to get a spacecraft off the Earth and into space. And how managers at NASA can actually navigate a spacecraft to another planet? And how does a gravity assist work? And how do they get them into orbit? And how do they land? So many questions…
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News today from the National Science Foundation will have an impact on how scientists are able to study…. well, impacts. A team of geologists has developed a new way of determining the size and frequency of meteorites that have collided with Earth in the past. By studying sediments found on the ocean floor and looking for isotopes of the rare element osmium, scientists can now figure out not only when a meteorite impact occurred in Earth’s history, but also the size of the meteorite. One of the most exciting benefits of this new technique is the potential for identifying previously unknown impacts.
When meteorites collide with Earth, they carry a different osmium isotope ratio than the levels normally seen throughout the oceans.
“The vaporization of meteorites carries a pulse of this rare element into the area where they landed,” says Rodey Batiza of the National Science Foundation, which funded the research. “The osmium mixes throughout the ocean quickly. Records of these impact-induced changes in ocean chemistry are then preserved in deep-sea sediments.”
François Paquay, a geologist at the University of Hawaii at Manoa analyzed samples from two sites where core samples of the ocean floor were taken, one near the equatorial Pacific and another located off of the tip of South Africa. He measured osmium isotope levels during the late Eocene period, a time during which large meteorite impacts are known to have occurred.
“The record in marine sediments allowed us to discover how osmium changes in the ocean during and after an impact,” says Paquay.
The scientists believe this new approach to estimating impact size will become an important complement to a more well-known method based on iridium.
Paquay’s team also used this method to make estimates of impact size at the Cretaceous-Tertiary (K-T) boundary 65 million years ago. Since the osmium carried by meteorites is dissolved in seawater, the geologists were able to use their method to estimate the size of the K-T meteorite as four to six kilometers in diameter. The meteorite was the trigger, scientists believe, for the mass extinction of dinosaurs and other life forms.
But Paquay doesn’t believe this method will work for events larger than the K-T impact. With such a large meteorite impact, the meteorite contribution of osmium to the oceans would overwhelm existing levels of the element, making it impossible to sort out the osmium’s origin.
But it will be interesting to follow this to see if new, unknown impacts in Earth’s history can be discovered.
Original News Source: Eureka Alert
So what did exist before the Big Bang? This question would normally belong in the realms of deep philosophical thinking; the laws of physics have no right to probe beyond the Big Bang barrier. There can be no understanding of what was there before. We have no experience, no observational capability and no way of travelling back through it (we can’t even calculate it), so how can physicists even begin to think they can answer this question? Well, a new study of Loop Quantum Gravity (LQG) is challenging this view, perhaps there is a way of looking into the pre-Big Bang “universe”. And the conclusion? The Big Bang was more of a “Big Bounce”, and the pre-bounce universe had the same physics as our universe… just backwards… Confused? I am…
LQG is a tough theory to put into words, but it basically addresses the problems associated with the incompatibilities behind quantum theory and general relativity, two crucial theories that characterize our universe. If these two theories are not compatible with each other, the search for the “Theory Of Everything” will be hindered, disallowing gravity to merge with the “Grand Unified Theory” (a.k.a. the electronuclear force). LQG quantizes gravity, thereby providing a possible explanation for gravity and a possible key to unlocking the Theory Of Everything. However, from the outset, LQG has many critics as there is little direct or indirect evidence backing up the theory.
See the previous Universe Today article on Loop Quantum Gravity»
Regardless, much work is being done into this area of research. The primary consequence to come from LQG is that it predicts that the Big Bang which occurred 13.7 billion years ago was actually a “Big Bounce”; our universe is therefore the product of a contracting universe before the Big Bang. The previous universe (or our universe “twin”) contracted to a single point (which could be interpreted as a “Big Crunch”) and then rebounded in a Big Bounce to produce the Big Bang as we’ve learned to accept as the birth of the universe as we know it. But until now, although the pre-bounce universe has been predicted, its characteristics could not be known. No information about the pre-bounce universe could be observed in today’s universe, the Big Bounce causes a “cosmic amnesia”, destroying all information of the previous universe.
Now, physicists Alejandro Corichi from Universidad Nacional Autónoma de México and Parampreet Singh from the Perimeter Institute for Theoretical Physics in Ontario are working on a simplified Loop Quantum Gravity (sLQG) theory where they approximate the value of the “quantum constraint”, a key equation in the LQG theory. What happens next is a little surprising. From their calculations, it would appear that a universe, identical to our own, with identical mechanics, existed before the Big Bounce.
“…the twin universe will have the same laws of physics and, in particular, the same notion of time as in ours. The laws of physics will not change because the evolution is always unitary, which is the nicest way a quantum system can evolve. In our analogy, it will look identical to its twin when seen from afar; one could not distinguish them.” – Parampreet Singh
We are not talking about an alternate dimension; we are talking about an identical universe with the same space-time and quantum characteristics as our own. If we look at our universe now (13.7 billion years post-bounce), it would be identical to the universe 13.7 billion years before the Big Bounce. The only difference being the direction of time would be opposite; the pre-bounce universe would be reversed.
“In the universe before the bounce, all the general features will be the same. It will follow the same dynamical equations, the Einstein’s equations when the universe is large. Our model predicts that this happens when the universe becomes of the order 100 times larger than the Planck size. Further, the matter content will be the same, and it will have the same evolution. Since the pre-bounce universe is contracting, it will look as if we were looking at ours backward in time.” – Parampreet Singh
Analysing what happened before the Big Bang is only part of the story. By making this approximation of a key LQG equation, Singh and Corichi are working on models where galaxies and other physical structures leave an imprint in the pre-bounce universe to influence the post-bounce universe. Would these structures be distributed in similar ways? Will the structures in one universe be similar or identical to structures in the other universe? There may also be an opportunity to look into the future of this universe and predict whether the conditions are right for another Big Bounce (once can imagine repeated bounces, producing a cycle of universes).
For now, this research is highly theoretical and any observational evidence will remain sparse for the time being. Although this is the case, it does begin to probe the big question and may push physics a bit closer toward describing what existed before the Big Bang…
Source: Physorg.com
When it rains space news from Russia, it pours. Not only did the news break today about the Russian Space Agency’s plans to send monkeys to Mars, but also, Russia wants to build an Earth-orbiting factory to build large, interplanetary ships that might be too large to launch from Earth. Additionally, Roscosmos, the Russian space agency said that beginning in 2010, they will likely terminate ferrying space tourists to the International Space Station.
According to the head of Roscosmos Anatoly Perminov, the space agency proposed building a manned assembly complex in Earth orbit and the Russian Security Council supported the idea in an April 11, 2008 meeting. No word on exactly when an orbiting spaceship assembly line would be constructed, but Perminov said it likely wouldn’t be built until after the ISS is completed, which they said would be about 2020. Also, no word if the interplanetary ships will be built for humans or monkeys.
As far as curtailing the program that brings space tourists to the ISS, the Perminov said the increase in crew size on the ISS from the current three members to six in 2009, and then the proposed retirement of the space shuttle in 2010, will put “growing pressure†on the Russian Soyuz spacecraft that carries crews and supplies to the space station. Perminov said they will no longer accept proposals from space tourists, adding that space tourism shouldn’t interfere with scientific research. Roscosmos teamed up with the company Space Adventures beginning in 2001 to bring tourists to the ISS, which seemed to be a fairly lucrative program for the cash-strapped Russian space agency. Existing contracts to bring tourists to the station will be fulfilled, Perminov said.
Dennis Tito became the first space tourist in 2001 when he paid $20 million to ride the Soyuz for a week-long stay on the ISS. The next (and sixth) tourist will be game developer Richard Garriott, scheduled for a Soyuz flight in October 2008.
Original News Source: Lenta Ru (translated)
Combining the exhilaration of racing, with the power of rocket engines and the appeal of video gaming, Rocket Racing League (RRL) CEO Granger Whitelaw said the new sports entertainment league is the sport for geeks. “We haven’t really had a sport, but now we do,†said Whitelaw, a self-professed geek at a press conference on April 14, 2008. “We now have one where we combine real athletes and real heroes with rocket planes and with gaming that we love to do so much.†At the press conference, members of the RRL announced its live first exhibition, to be held August 1st and 2nd at the EAA AirVenture airshow in Oshkosh, Wisconsin, one of the largest airshows in the world. Additional exhibitions later in the year were also announced.
Whitelaw said in this new “futuristic and innovative sport†pilots will race rocket powered aircraft through a three-dimensional track in the sky. The planes will compete side by side, and feature multiple races pitting up to ten Rocket Racers with a 4-lap, multiple elimination heat format on a 5-mile “Formula One”-like closed circuit raceway. The Rocket Racer pilots will view the “raceway in the sky” via cockpit in-panel and 3D helmet displays. On the ground, spectators at airshows can watch the action live, or on screens that include the 3-D raceway. And in this ultimate reality show, viewers at home can watch on television, and gamers can take part with virtual competition.
In August, for the first exhibition, two Rocket Racers will compete head-to-head in a demonstration race and the expected 700,000 people in attendance at EAA AirVenture will witness the racing action live on multiple 50 foot large projection screens.
The RRL will have multiple aerial cameras and 5 cameras on each plane.
Whitelaw said that although they believe their rocket planes are some of the safest air vehicles available, they will take multiple precautions to ensure crowd safety at the live events, specifically, never flying directly at the crowds. “Every step we are taking with the development of the rocket racers now, involves safety considerations,†Whitelaw said.
Each of the four heats will last about 10-12 minutes, with pitstops of 10-12 minutes. “It will similar to periods in hockey or football, and will give us time to do color and introduce the pilots,†said Whitelaw. The RRL will be better than football, he said, which only has about seven minutes of real action in a game with the rest being just talk. “It will be very exciting and it will be all about competition.â€
Whitelaw said the RRL has been offered two television deals, and that all the competitions will be televised. “We are going to reach out to different audiences, both in the US and worldwide,†he said.
Whitelaw predicted the RRL video game will also be a big success. The RRL built a video game simulator 2 years ago that they have set up at air shows for people to try. “The tent is usually full all day with young and old alike…this is really going to bring out a new fan base,†Whitelaw said. The full video game won’t be released until the league is actually in operation.
Here are the remaining exhibition dates:
Reno National Championship Air Races (Reno, NV) – September 10-14
X Prize Cup (Las Cruces, NM) – TBD 2008
Aviation Nation, Nellis AFB, (Las Vegas, NV) – November 8-9
In these days of environmental concerns, Whilelaw was asked about the types of fuel used in the rocket planes. “I like to say that 95% of our fuel grows on trees,†he said. “We use cryogenic compressed liquid oxygen for the main part of the thrust for the rocket planes. The Armadillo plane uses ethanol. The X-COR rocket racer uses kerosene. We’re trying to be environmentally friendly as possible.â€
The RRL was founded in 2005 by Whitelaw, a two-time Indianapolis 500 winning team partner and X PRIZE Chairman and CEO Peter Diamandis. For more information on the Rocket Racing League, visit www.rocketracingleague.com.
Original News Source: RRL Press Conference
Ian reported yesterday on the high definition topographical maps recently released by the Japanese SELENE mission, also known as Kaguya, which will provide exact locations of essential minerals to future lunar explorers. And now, via Emily Lakdawalla at the Planetary Society comes more from Kaguya — movies of an Earthrise and Earthset from the moon. While the movies don’t provide much as far as scientific data, they are off the charts as far being aesthetically pleasing and just tremendously magnificent. Emily grabbed individual frames from the longer, but smoother high-definition movies that the Japanese Space Agency JAXA created from the HD Camera on board the moon-orbiting Kaguya to create quick little movies. Above is the Earthrise quick movie.
Here’s the quick Earthset movie Emily created. And here’s the links to the hi-def versions at JAXA for Earthrise and Earthset.
However, these longer and smoother movies are still only 25% of the full resolution of the movies. JAXA has not been releasing the full resolution Kaguya data on the internet, as they are “saving” the really high-def stuff for commercial and educational purposes.
Emily reported that HD camera on board the Kaguya spacecraft generates too much data for live transmission; instead the video is compressed and stored within the camera system. Then, it takes about 20 minutes to transmit a 1-minute video to Earth. See Emily’s post for more info.
Original News Source: The Planetary Society
One thing is certain, Wolf-Rayet stars produce some interesting
science. In this week’s portrait we see a distorted bubble produced
by a moving star blowing a strong stellar wind into a surrounding
uniform interstellar medium – yet is isn’t uniform. What exactly is
going on here?
Hanging out some 11,736 light years away in the southern constellation
of Carina (RA 10:17:24.0 Dec -57:55:18), NGC 3199 is classed as a
diffuse nebula or supernova remnant. Discovered by John Herschel in
1834, it has been known throughout historic astronomy observations as
bright, large, crescent-shaped nebula with embedded stars, but modern
astronomy shows it as much more. It’s being pushed along by
Wolf-Rayet star 18.
Says Dr. Michael Corcoran: “Wolf-Rayet stars (named for their
discoverers) are very large, massive stars (stars which are about 20
times bigger than the sun) nearly at the end of their stellar lives.
As these stars age, material which the stars have cooked up in their
central nuclear furnaces (like carbon and oxygen) gradually reach the
surface of the star. When enough material reaches the surface, it
absorbs so much of the intense light from the star that an enormously
strong wind starts to blow from the star’s surface. This wind becomes
so thick that it totally obscures the star – so when we look at a
Wolf-Rayet star, we’re really just seeing this thick wind. The amount
of material which the wind carries away is very large – typically, a
mass equivalent to that of the entire earth is lost from the star each
year. The mass loss is so large that it significantly shortens the
star’s life, and as you can imagine has important effects on the space
surrounding the star too. We think that very massive stars become
Wolf-Rayet stars just before they explode as supernova (though no one
has yet seen such a star explode).
At magnitude 11, NGC 3199 is observable with larger amateur
telescopes, but the crescent shape is cause for study by some of the
finest research telescopes and astronomers in the world. Through
optical observations, the ring nebula and cavities around WF stars have
painted a history of mass loss in these highly evolved stellar
curiosities. By studying molecular gases associated with Wolf-Rayet
stars, it appears that some materials seem to be avoiding optical
emission.
In reading scientific reports submitted by A. P. Marston, molecular
gas has already been observed around Wolf-Rayet Star 18 – the first to
confirm the presence of HCN, HCO+, CN, and HNC and molecules. This
makes the Wolf-Rayet ring nebula NGC 3199 very unique and filled
associated molecular gas that took the form clumpy ejecta and
interstellar material. At one time, NGC 3199’s formation was believed
to be caused by bow shock, but current data now shows the associated
Wolf Rayet star is moving at a right angle to its enveloping
environment. Could this be an indication that something else is at
work here? Astronomers seem to think so.
According to their information, it is possible the northern area of
the optically bright nebula is being torn apart by a possible blowout
of Wolf Rayet wind. This, in turn, affects the surrounding ejecta and
could very well account for the observed velocity. By modeling
molecular abundances, the central Wolf Rayet star could be contributing a
portion of its material to this nebula as ejecta. Despite its still
unsolved mysteries, NGC 3199 is a stunning portrait. J.E. Dyson and
Ghanbari summed it up best when they described it as an “interstellar
snow plough”.
This week’s awesome astronomy picture is the work of Ken Crawford, taken at Macedon Ranges Observatory.
Says Ken: “This image was taken using an Apogee CCD Camera that uses primarily Narrow Band data which is color mapped mixed with RGB for natural star colors and back ground balancing. The bright blue area shows lots of OIII (ionized oxygen) signal which really shows the direction of the star movement well. The star is said to be moving at about 60 km/s through the interstellar gas.”
Russia has a long history of scientific discovery and space exploration through the use of animals. Beginning with space dog Laika in 1957, the space program expanded to run tests on other dogs (many returned safely to Earth) and eventually monkeys. Although the monkey testing program was stopped through lack of funding in the mid-1990’s, the nation has announced plans to send the closest relation to humans to a place where no man has gone before: Mars. And here’s us thinking it will be a human first stepping onto the Martian surface…
I must admit, I had to read the story twice before I believed it. Russia wants to send monkeys not only into space, but to Mars. I had an idea that monkeys (or more specifically macaques) were used in space missions in the past, but in my mind this was in the past and would be considered cruel in this day and age. But hold on, aren’t macaques used in medical experiments the world over anyway? Why is it so shocking that macaques should be chosen to pioneer interplanetary travel before mankind?
These questions are emotive (and controversial) and will cause much debate internationally. Many will believe that the experimental testing on animals in the ultra-modern world of space travel will seem barbaric, but there are some serious problems we might definitively answer through the use of macaque space travel. First and foremost, due to the interplanetary radiation we expect to be bathed in during a transit to Mars, by studying a macaque’s physiology during the long journey we may be able to learn how the human body will react to larger than normal doses. The fact remains, monkeys are genetically close to humans, its little wonder that we turn to them for answers.
To this end, monkeys at the Sochi Institute of Medical Primatology, at Vesyoloye near the Black Sea, have begun the selection process for the ultimate medical animal testing experiment. The institute has a long history of involvement in the Russian and Soviet space program. Sochi was the training facility for the first monkeys into space in 1983. Abrek and Bion had a five-day trip around Earth and were returned safely in Kazakhstan and rehabilitated to live “normal lives”. Two years after this historic flight, monkeys Verny and Gordy spent seven days in space. In 1987, Dryoma and Yerosha spent a record breaking (for a monkey-assisted flight) two-weeks in space. Interestingly, Dryoma was given to Cuban leader Fidel Castro as a gift. Following this, in 1989, 1992 and 1996, three two-week flights were carried out until funding for the project ran out. Now experiments have been continued on Earth to simulate weightlessness.
Now, to revitalize Sochi’s history of macaque space flight, they are beginning a two-year program to select 40 monkeys to be sent to the Institute of Biomedical Problems in Moscow so tests can be continued into aerospace biomedicine. This will culminate in a possible primate mission to Mars.
“People and monkeys have approximately identical sensitivity to small and large radiation doses, so it is better to experiment on the macaques, but not on dogs or other animals.” Boris Lapin, Institute Director.
Critics of the program are frustrated by the use of animal testing in any capacity, but remain realistic about the situation. “Humanity sacrifices more than 100 million animals a year in the name of health and beauty. It’s time to think of an alternative to experiments with animals,” says Andrei Zbarsky of the conservation group the World Wildlife Fund (WWF).
“…certainly, I feel sorry for the monkeys, they might die, but the experiments are necessary to preserve the lives of the cosmonauts who will fly to Mars in future” – Anaida Shaginyan, Institute Researcher.
This will be a controversial measure by the Russian space program and they are expecting resistance from their European partners. Although monkeys and other animals are used in medical science here on Earth, it might prove too distasteful and cruel for most, but possibly the only means to measure the physical impact on the human body after a long trip to Mars.
Source: BBC
The Japanese SELENE lunar orbiter has returned some of the most detailed maps of the Moon to date. The new collection of high-definition maps includes topological data and mineral location. Critically, the locations of uranium, thorium and potassium have been mapped, essential for mission planners when considering the future of manned settlements on the Moon. Seeing the lunar relief mapped to such fine detail makes for an impressive sight. So far six million data points have been collected and there’s more to come…
The SELENE mission was launched on September 14th, 2007 from Tanegashima Space Center on a H-IIA carrier rocket. SELENE stands for “Selenological and Engineering Explorer”, but Selene was also the Greek lunar deity. The orbiter arrived into lunar orbit on October 3rd and began science operations soon after. Since then, the spacecraft has been using a large number of instruments to characterise the surface of the Moon from analysing its mineral distribution to measuring its terrain. It has been described as the largest Moon mission since the US Apollo program.
According to the JAXA press release, these new maps are ten-times more accurate than previous maps. Using the laser altimeter (LALT) instrument, 3D data of the shapes and altitudes of surface features are promising to give the most advanced relief mapping capabilities ever performed on a planetary body other than the Earth. It has also been indicated that deposits of uranium, potassium and thorium have been pinpointed through the use of one of its onboard spectrometers. This will have massive implications for the future of manned exploration of the natural satellite. It is likely that a nuclear source of energy would be required for future lunar settlements, if there are quantities of uranium to be mined, this will have an impact on where the settlement should be located.
So, when venturing out onto the cold, lonely lunar surface, be sure to pack the newest edition of the Selene high-definition map to plot your journey…
By combining ground-based optical observations with space-borne infrared images from Spitzer, an incredible new view of mysterious Omega Centauri has been revealed. Astronomers have had a hard time identifying what type of galaxy Omega Centauri actually is, so any new information on the cluster of millions of stars is needed. By combining observations in different wavelengths, stars of different ages are highlighted, possibly aiding our understanding about the origins of Omega Centauri and answer the question: Why is this galaxy so strange?
As discussed in an article last week, Omega Centauri is of particular interest to astrophysicists. Over the years this strange collection of stars has been classified as a single star (by Ptolemy), a nebula (by Halley in 1677) and a globular cluster (by Herschel in the 1830’s). Now it is believed that this dwarf galaxy may be a survivor of an ancient collision with the Milky Way which stripped away its outermost stars. This is why it may look like a globular cluster now, but doesn’t have globular cluster characteristics. For a start Omega Centauri is too big (ten times bigger than the largest globular clusters) and it contains stars of many generations (globular clusters usually contain one generation). Recent observations also show a very fast rotating galactic core, revealing the presence of an intermediate-size black hole… the missing link connecting stellar black holes with supermassive black holes. Exciting stuff.
Putting the scientific implications to one side for now, I can’t help but stare at this stunning view of this interesting cluster of star systems. I’m used to monochromatic images of space with some false-colour thrown in for good measure; this image seems to be different. Very quickly we are able to gain an insight to the dispersion of star generations, just by looking at the image. A quick glance shows the majority of young stars are clustered toward the middle (the blue stars), older red giants located around the outside of the galaxy (the red/yellow stars).
According to the NASA news release, where green and red dots overlap, yellow dots appear. These are NASA Spitzer Space Telescope stars observed in infrared. We know that these emissions come from old, large and dusty stars, the red giants. The blue dots are younger stars, much like our Sun, as observed in optical and near-infrared wavelengths by the National Science Foundation’s Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile. I’ve included a little section from the main image with the two types of star ringed and annotated (pictured).
These new Spitzer observations show very little dust around any of the dimmest red giants and the space between the stars also does not seem to contain much dust (as interstellar dust would glow infrared radiation as nearby stars heat it). Astronomers have concluded that any dust within the cluster is quickly destroyed or lost from the galaxy.
Source: NASA