Space and astronomy news
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When you think about the best pictures in astronomy, almost every one is a nebula; the pillars of creation in the Eagle Nebula, or the complex Helix Nebula – or my personal favorite, the Ring Nebula. They’re beautiful, wispy clouds of gas and dust that signify both the birth and death of stars. Today we give tribute to nebulae.
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Nebulae – Transcript and show notes.
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A series of images put together to form a movie of the Mars Phoenix lander’s telltale instrument show the telltale waving wildly in the Martian wind. According to Phoenix scientists, movement in one image seemed to be “out-of-phase” with other images, possibly indicating a dust devil whirled nearby or even over the lander. Preliminary analysis of the images taken right before and after the passing of this possible dust devil indicates winds from the west at 7 meters per second. The image taken during the possible dust devil shows 11 meters per second wind from the south.
These images were taken by the lander’s Surface Stereo Imager (SSI) on the 136th Martian day, or sol, of the mission (Oct. 12, 2008). Documenting the telltale’s movement helps mission scientists and engineers determine what the wind is like on Mars. The telltale was built by the University of Aarhus, Denmark, and is part of the lander’s Meteorological Station (MET), developed by the Canadian Space Agency.
Also, Phoenix’s robotic arm successfully delivered soil into oven six of the lander’s thermal and evolved-gas analyzer (TEGA) on Monday, Oct. 13, or Martian day (sol) 137 of the mission.
Six of eight ovens have been used to date.
TEGA’s tiny ovens heat the soil to as high as 1,800 degrees Fahrenheit (1,000 degrees Celsius). The lab’s or mass spectrometer analyzes the gases derived from heating the soil. Mission scientists will continue to research and analyze the soil samples in the coming months, long after Phoenix stops operating on the surface.
Phoenix is gradually getting less power as the sun drops below the horizon.
“My entire team is working very hard to make use of the power we have before it disappears,” said William Boynton of the University of Arizona, Tucson, the lead scientist for TEGA. “Every time we fill an oven, we potentially learn more about Mars’ geochemistry.”
Source: Phoenix News Site
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This week the Carnival of Space moves to the Lounge of the Lab Lemmings. We’ve got news about dark matter, and how cosmology has inspired jazz.
Click here to read the Carnival of Space #75
And if you’re interested in looking back, here’s an archive to all the past carnivals of space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let me know if you can be a host, and I’ll schedule you into the calendar.
Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out.
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Another week, another roundup of your questions. This week listeners asked: what is galactic dust anyway, and where does it come from? Why can photons move at the speed of light? And how can astronomers know what happened right after the Big Bang? And there’s even more. If you’ve got a question for the Astronomy Cast team, please email it in to [email protected] and we’ll try to tackle it for a future show. Please include your location and a way to pronounce your name.
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Galactic Dust, the Speed of Photons, and the Big Bang Calculations – Transcript and show notes.
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You know what this show needs? More aliens. Since we don’t seem to have any visiting right now, we’re going to have to find some. SETI is an acronym. It stands for the Search for Extraterrestrial Intelligence. But there’s more to SETI than just putting up a radio telescope and hoping to catch a glimpse of an alien television broadcast.
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The Search for Extraterrestrial Intelligence – Transcript and show notes.
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Maybe the fictional Dr. Frankenstein wasn’t so crazy after all. Two scientists have resurrected an old experiment, breathing life into a “dead” notion about how life began on our planet. New analysis shows that lightning and gases from volcanic eruptions could have given rise to the first life on Earth.
“It’s alive!”…
Back in the early 1950s, two chemists Stanley Miller and Harold Urey of the University of Chicago did an experiment that tried to recreate the conditions of a young Earth to see how the building blocks of life could have arisen. They used a closed loop of glass chambers and tubes with water and different mixes of hydrogen, ammonia, and methane; the gases thought to be in Earth’s atmosphere billions of years ago. Then they zapped the mixture with an electrical current, to try and confirm a hypothesis that lightning may have triggered the origin of life. After a few days, the mixture turned brown.
When Miller analyzed the water, he found it contained amino acids, which are the building blocks of proteins — life’s toolkit. The spark provided the energy for the molecules to recombine into amino acids, which rained out into the water. The experiment showed how simple molecules could be assembled into the more complex molecules necessary for life by natural processes, like lightning in Earth’s primordial atmosphere.
But there was a problem. Theoretical models and analyses of ancient rocks eventually convinced scientists that Earth’s earliest atmosphere was not rich in hydrogen, so many researchers thought the experiment wasn’t an accurate re-creation of early Earth. But the experiments performed by Miller and Urey were ground-breaking.
“Historically, you don’t get many experiments that might be more famous than these; they re-defined our thoughts on the origin of life and showed unequivocally that the fundamental building blocks of life could be derived from natural processes,” said Adam Johnson, a graduate student with the NASA Astrobiology Institute team at Indiana University, Bloomington. Johnson is the lead author on a paper that resurrects the old origin-of-life experiments, with some tantalizing new findings.
Miller died in 2007. Two former graduate students of Miller’s –geochemists Jim Cleaves of the Carnegie Institution of Washington (CIW) in Washington, D.C., and Jeffrey Bada of Indiana University, Bloomington–were examining samples left in Miller’s lab. They found the vials of products from the original experiment and decided to take a second look with updated technology. Using extremely sensitive mass spectrometers at NASA’s Goddard Space Flight Center Cleaves, Bada, Johnson and colleagues found traces of 22 amino acids in the experimental residues. That is about double the number originally reported by Miller and Urey and includes all of the 20 amino acids found in living things.
Miller actually ran three slightly different experiments, one of which injected steam into the gas to simulate conditions in the cloud of an erupting volcano. “We found that in comparison to Miller’s classic design everyone is familiar with from textbooks, samples from the volcanic apparatus produced a wider variety of compounds,” said Bada.
This is significant because thinking on the composition of Earth’s early atmosphere has changed. Instead of being heavily laden with hydrogen, methane, and ammonia, many scientists now believe Earth’s ancient atmosphere was mostly carbon dioxide, carbon monoxide, and nitrogen. But volcanoes were active during this time period, and volcanoes produce lightning since collisions between volcanic ash and ice particles generate electric charge. The organic precursors for life could have been produced locally in tidal pools around volcanic islands, even if hydrogen, methane, and ammonia were scarce in the global atmosphere.
So, this breathes life into the notion of lightning jump-starting life on Earth. Although Earth’s primordial atmosphere was not hydrogen-rich, gas clouds from volcanic eruptions did contain the right combination of molecules. Is it possible that volcanoes seeded our planet with life’s ingredients? While no one knows what happened next, the researchers are continuing their experiments in an attempt to determine if volcanoes and lightning are the reasons we’re here.
The paper was published in Science on Oct. 17, 2008
Sources: NASA, ScienceNOW
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There’s a new spacecraft in Earth orbit, with a really “far out” mission: to map the outer solar system. NASA’s Interstellar Boundary Explorer mission, or IBEX launched successfully from the Kwajalein Atoll in the Pacific Ocean at 1:47 p.m. EDT, Sunday, from an Orbital Sciences Pegasus XL launch vehicle. IBEX will be the first spacecraft to image and map dynamic interactions taking place in the outer solar system. The two Voyager probes sent back a limited amount of information about the region of space where our solar system ends and interstellar space begins. But beyond that, not much is known about this area. The region is about three times further from the sun than the orbit of planet Pluto. “No one has seen an image of the interaction at the edge of our solar system where the solar wind collides with interstellar space,” said IBEX Principal Investigator David McComas of the Southwest Research Institute in San Antonio. “We know we’re going to be surprised.”
The spacecraft separated from the third stage of its Pegasus launch vehicle at 1:53 p.m. and immediately began powering up components necessary to control onboard systems. The operations team is continuing to check out spacecraft subsystems.
“After a 45-day orbit raising and spacecraft checkout period, the spacecraft will start its exciting science mission,” said IBEX mission manager Greg Frazier of NASA’s Goddard Space Flight Center in Greenbelt, Md.
“The heliosphere’s boundary region is enormous, and the Voyager crossings of the termination shock, while historic, only sampled two tiny areas 10 billion miles (16 billion km) apart,” NASA scientist Eric Christian said.
Voyager 1 passed the inner boundary in 2004 and Voyager 2 crossed over last year.
The solar wind, a stream of electrically conducting gas continuously moving outward from the sun at 1 million mph (1.6 million kph), blows against this interstellar material and forms a huge protective bubble around the solar system. This bubble is called the heliosphere.
As the solar wind reaches far beyond the planets to the solar system’s outer limits, it encounters the edge of the heliosphere and collides with interstellar space. A shock wave is present at this boundary.
“Every six months, we will make global sky maps of where these atoms come from and how fast they are traveling. From this information, we will be able to discover what the edge of our bubble looks like and learn about the properties of the interstellar cloud that lies beyond the bubble,” physicist Herb Funsten of the U.S. Department of Energy’s Los Alamos National Laboratory.
Sources: NASA, Reuters
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NASA’s Fermi Gamma-ray Space Telescope discovered the first pulsar that beams only in gamma rays. A pulsar is a rapidly spinning neutron star, the crushed core left behind when a massive sun explodes. Astronomers have cataloged nearly 1,800 pulsars. Although most were found through their pulses at radio wavelengths, some of these objects also beam energy in other forms, including visible light and X-rays. However, this new object only pulses at gamma-ray energies. “This is the first example of a new class of pulsars that will give us fundamental insights into how these collapsed stars work,” said Stanford University’s Peter Michelson, principal investigator for Fermi’s Large Area Telescope.
The gamma-ray-only pulsar lies within a supernova remnant known as CTA 1, which is located about 4,600 light-years away in the constellation Cepheus. Its lighthouse-like beam sweeps Earth’s way every 316.86 milliseconds. The pulsar, which formed about 10,000 years ago, emits 1,000 times the energy of our sun.
“We think the region that emits the pulsed gamma rays is broader than that responsible for pulses of lower-energy radiation,” explained team member Alice Harding at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The radio beam probably never swings toward Earth, so we never see it. But the wider gamma-ray beam does sweep our way.”
Scientists think CTA 1 is only the first of a large population of similar objects.
“The Large Area Telescope provides us with a unique probe of the galaxy’s pulsar population, revealing objects we would not otherwise even know exist,” says Fermi project scientist Steve Ritz, also at Goddard.
Fermi’s Large Area Telescope scans the entire sky every three hours and detects photons with energies ranging from 20 million to more than 300 billion times the energy of visible light. The instrument sees about one gamma ray every minute from CTA 1, enough for scientists to piece together the neutron star’s pulsing behavior, its rotation period, and the rate at which it is slowing down.
The pulsar in CTA 1 is not located at the center of the remnant’s expanding gaseous shell. Supernova explosions can be asymmetrical, often imparting a “kick” that sends the neutron star careening through space. Based on the remnant’s age and the pulsar’s distance from its center, astronomers believe the neutron star is moving at about a million miles per hour — a typical speed.
Source: NASA
Costa Rican engineering students invent a coffee percolator for use in orbit
[/caption]Imagine: You’ve just woken up on board the space station half-way through your six-month mission in zero-gravity. You probably feel a little home sick and you crave a drink that will pick up your mood, preparing you for a tough day of overseeing experiments in Kibo and keeping up with your station schedule for the day. You go to the galley for some coffee. Instant, bad tasting coffee at that. You put the instant coffee container into the microwave and heat up the sour, plastic-tasting brew. Did that make you feel any better? Or did it just make you crave the smell of real, freshly ground coffee beans you’re used to on Earth?
Franklin Chang-Diaz, a veteran NASA astronaut who spent a lot of time on the International Space Station (ISS), knows all too well the taste of really bad microwaved space coffee. So, in an effort to make life a little better for the current astronauts in orbit, Chang has asked two engineering students to design a machine that can percolate fresh-ground coffee in zero gravity…
It may seem like a trivial problem. After all, astronauts on board the ISS are bound to suffer some inconveniences whilst working on space; they are strong, intelligent individuals who understand the sacrifices they need to make to belong to this exclusive group of space pioneers. However, as we spend more time in space, there is an increasing desire for the creature comforts of home, especially if you have to spend six months on board a cramped and (soon-to-be) crowded orbital outpost.
In an effort to confront a personal grievance with his experiences in space, Franklin Chang-Diaz, a seasoned NASA astronaut who has flown on seven Shuttle missions and helped to build the ISS, has approached two students at the Technological Institute of Costa Rica to design and build a coffee machine. But this isn’t any ordinary coffee machine, it is a coffee percolator that works in zero g, dispensing with the need for instant microwaved coffee.
View the Telegraph news report on the “Coffee Infuser” »
So, Daniel Rozen and Josue Solano came up with a solution. The biggest problems faced when wanting to percolate hot water through ground coffee in space are, a) there’s no gravity to draw the water through the coffee, b) liquids will float in globules and stick to instrumentation, and c) hot globules of water will create vapour and will probably be quite dangerous (after all, the last thing the ISS crew will need are scalding blobs of water flying around!). Enter the secretive “Coffee Infuser.”
“We turn on the switch. The machine will heat the water to 90 degrees centigrade, the ideal temperature for a cup of coffee,” Rozen explains. “Once the water reaches that temperature, we direct the water which is found in the heating chamber towards where the container is found, resulting in a delicious cup of coffee.”
In an intense environment where crew well-being is critical to mission success or failure, the idea of a space-age coffee infuser seems like a good idea. However, in space, where mass dictates how much a mission costs, the Costa Rican engineers will have to find a way of either making their prototype a lot smaller or integrate it seamlessly into a new piece of kit. Until a smaller version is available I doubt it will be considered to be a critical appliance for the station… (although it would be nice to wake up to the smell of freshly brewed coffee when the Sun is rising over the limb of the Earth…)
Source: Telegraph Online
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We’re learning more about black holes and the early universe all the time, with the help of all the amazing ground-based telescopes astronomers now have at their disposal. Astronomers think that many – perhaps all – galaxies in the universe contain massive black holes at their centers. New observations with the Submillimeter Array now suggest that such colossal black holes were common even 12 billion years ago, when the universe was only 1.7 billion years old and galaxies were just beginning to form. The new conclusion comes from the discovery of two distant galaxies, both with black holes at their centers, which are involved in a spectacular collision.
4C60.07, the first of the galaxies to be discovered, came to astronomers’ attention because of its bright radio emission. This radio signal is one telltale sign of a quasar – a rapidly spinning black hole that is feeding on its home galaxy.
When 4C60.07 was first studied, astronomers thought that hydrogen gas surrounding the black hole was undergoing a burst of star formation, forming stars at a remarkable rate – the equivalent of 5,000 suns every year. This vigorous activity was revealed by the infrared glow from smoky debris left over when the largest stars rapidly died.
The latest research, using the keen vision of the Submillimeter Array of eight radio antennas located in Hawaii, revealed a surprise. 4C60.07 is not forming stars after all. Indeed, its stars appear to be relatively old and quiescent. Instead, prodigious star formation is taking place in a previously unseen companion galaxy, rich in gas and deeply enshrouded in dust, which also has a colossal black hole at its center.
“This new image reveals two galaxies where we only expected to find one,” said Rob Ivison (UK Astronomy Technology Centre), lead author of the study that will be published in the Monthly Notices of the Royal Astronomical Society. “Remarkably, both galaxies contain supermassive black holes at their centers, each capable of powering a billion, billion, billion light bulbs. The implications are wide-reaching: you can’t help wondering how many other colossal black holes may be lurking unseen in the distant universe.”
Due to the finite speed of light, we see the two galaxies as they existed in the distant past, less than 2 billion years after the Big Bang. The new image from the Submillimeter Array captures the moment when 4C60.07 ripped a stream of material from its neighboring galaxy, as shown in the accompanying artist’s conception. By now the galaxies have merged to create a football-shaped elliptical galaxy. Their black holes are likely to have merged and formed a single, more massive black hole.
The galaxies themselves show surprising differences. One is a dead system that has formed all of its stars already and used up its gaseous fuel. The second galaxy is still alive and well, holding plenty of dust and gas that can form new stars.
“These two galaxies are fraternal twins. Both are about the size of the Milky Way, but each one is unique,” said Steve Willner of the Harvard-Smithsonian Center for Astrophysics, a co-author of the paper.
“The superb resolution of the Submillimeter Array was key to our discovery,” he added.
Source: Smithsonian CfA