Aurora like the ones seen on October 24, 2011 as far south as Texas and Georgia would be commonplace on CoRoT-2b. (Image from the all-sky AuroraMax camera in Yellowknife, Ontario. http://twitpic.com/75owna )
Located 880 light-years away, a massive gas giant called CoRoT-2b orbits its star at a mere 2 million miles – less than a tenth the distance of Mercury’s orbit from the Sun. At this cozy proximity the star, CoRoT-2a, continually assaults the hot, gassy exoplanet with high-powered stellar winds and magnetic storms, stripping it of millions of kilograms of mass every day… and undoubtedly creating global auroras that rival even the most energetic seen on Earth.
But CoRoT-2b isn’t merely a tragic player in this stormy stellar performance; the planet itself may also be part of the cause.
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Almost 3 1/2 times the mass of Jupiter, CoRoT-2b (so named because it was discovered by the French Space Agency’s Convection, Rotation and planetary Transits space telescope, or CoRoT) orbits its star very rapidly, completing an orbit every 1.7 days. This in turn actually speeds up the rotation of the star itself thus generating even more magnetic activity, via a dynamo effect.
Caught up in this deadly dance, CoRoT-2b is losing mass at an estimated rate of 150 million billion kilograms of material every year! The planet would likely have a long comet-like tail of this stripped material trailing behind it.
Although this sounds like a lot, CoRoT-2b has enough mass to keep “spinning up” its star for thousands of billions of years.
Curiosity Mars Science Laboratory (MSL) rover blast off on Mars Trek. NASA's Mars Science Laboratory spacecraft, sealed inside its payload fairing atop the United Launch Alliance Atlas V rocket, clears the tower at Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida.The mission lifted off at 10:02 a.m. EST on Nov. 26, beginning an eight-month interplanetary cruise to Mars. Credit: Mike Deep/David Gonzales
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Atop a towering inferno of sparkling flames and billowing ash, Humankinds millennial long quest to ascertain “Are We Alone ?” soared skywards today (Nov. 26) with a sophisticated spaceship named ‘Curiosity’ – NASA’s newest, biggest and most up to date robotic surveyor that’s specifically tasked to hunt for the ‘Ingredients of Life’ on Mars, the most ‘Earth-like’ planet in our Solar System.
‘Mars Trek – Curiosity’s Search for Undiscovered Life’ zoomed to the heavens with today’s (Nov. 26) pulse pounding blastoff of NASA’s huge Curiosity Mars rover mounted atop a United Launch Alliance Atlas V rocket at 10:02 a.m. EST from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. Curiosity Mars Science Laboratory MSL) rover blasts off for Mars atop an Atlas V rocket on Nov. 26 at 10:02 a.m. EST from Cape Canaveral, Florida. Credit: Ken Kremer
Curiosity’s noble goal is to meticulously gather and sift through samples of Martian soil and rocks in pursuit of the tell-tale signatures of life in the form of organic molecules – the carbon based building blocks of life as we know it – as well as clays and sulfate minerals that may preserve evidence of habitats and environments that could support the genesis of Martian microbial life forms, past or present.
The Atlas V booster carrying Curiosity to the Red Planet vaulted off the launch pad on 2 million pounds of thrust and put on a spectacular sky show for the throngs of spectators who journeyed to the Kennedy Space Center from across the globe, crowded around the Florida Space Coast’s beaches, waterways and roadways and came to witness firsthand the liftoff of the $2.5 Billion Curiosity Mars Science Lab (MSL) rover. Curiosity Mars Science Laboratory (MSL) rover blasts off for Mars atop an Atlas V rocket on Nov. 26 at 10:02 a.m. EST from Cape Canaveral, Florida. The car-sized rover, Curiosity, which has 10 science instruments designed to search for signs of life, including methane, and to help determine if this gas is from a biological or geological source. Credit: Ken Kremer
The car sized Curiosity rover is the most ambitious, important and far reaching science probe ever sent to the Red Planet – and the likes of which we have never seen or attempted before.
“Science fiction is now science fact,” said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters at the post launch briefing for reporters at KSC. “We’re flying to Mars. We’ll get it on the ground… and see what we find.”
“’Ecstatic’ – in a word, NASA is Ecstatic. We have started a new Era in the Exploration of Mars with this mission – technologically and scientifically. MSL is enormous, the equivalent of 3 missions frankly.”
“We’re exactly where we want to be, moving fast and cruising to Mars.”
Curiosity Mars Science Laboratory (MSL) rover blasts off for Mars atop an Atlas V rocket on Nov. 26 at 10:02 a.m. EST from Cape Canaveral, Florida. Credit: Mike Deep/David Gonzales
NASA is utilizing an unprecedented, rocket powered precision descent system to guide Curiosity to a pinpoint touch down inside the Gale Crater landing site, with all six wheels deployed.
Gale Crater is 154 km (96 mi) wide. It is dominated by layered terrain and an enormous mountain rising some 5 km (3 mi) above the crater floor which exhibits exposures of minerals that may have preserved evidence of ancient or extant Martian life.
“I hope we have more work than the scientists can actually handle. I expect them all to be overrun with data that they’ve never seen before.”
“The first images from the bottom of Gale Crater should be stunning. The public will see vistas we’ve never seen before. It will be like sitting at the bottom of the Grand Canyon,” said McCuistion.
Topography of Gale Crater - Curiosity Mars rover landing site
Color coding in this image of Gale Crater on Mars represents differences in elevation. The vertical difference from a low point inside the landing ellipse for NASA's Curiosity Mars Science Laboratory (yellow dot) to a high point on the mountain inside the crater (red dot) is about 3 miles (5 kilometers). Credit: NASA
The 197 ft tall Atlas booster’s powerful liquid and solid fueled engines ignited precisely on time with a flash and thunderous roar that grew more intense as the expanding plume of smoke and fire trailed behind the rapidly ascending rockets tail.
The Atlas rockets first stage is comprised of twin Russian built RD-180 liquid fueled engines and four US built solid rocket motors.
The engines powered the accelerating climb to space and propelled the booster away from the US East Coast as it majestically arced over in between broken layers of clouds. The four solids jettisoned 1 minute and 55 seconds later. The liquid fueled core continued firing until its propellants were expended and dropped away at T plus four and one half minutes.
The hydrogen fueled Centaur second stage successfully fired twice and placed the probe on an Earth escape trajectory at 22,500 MPH.
The MSL spacecraft separates and heads on its way to Mars. Credit: NASA TV
The Atlas V initially lofted the spacecraft into Earth orbit and then, with a second burst from the Centaur, pushed it out of Earth orbit into a 352-million-mile (567-million-kilometer) journey to Mars.
MSL spacecraft separation of the solar powered cruise stage stack from the Centaur upper stage occurred at T plus 44 minutes and was beautifully captured on a live NASA TV streaming video feed.
“Our spacecraft is in excellent health and it’s on its way to Mars,” said Pete Theisinger, Mars Science Laboratory Project Manager from the Jet Propulsion Laboratory in California at the briefing. “I want to thank the launch team, United Launch Alliance, NASA’s Launch Services Program and NASA’s Kennedy Space Center for their help getting MSL into space.”
Curiosity punches through Florida clouds on the way to Mars. Credit: Mike Deep/David Gonzales
“The launch vehicle has given us a first rate injection into our trajectory and we’re in cruise mode. The spacecraft is in communication, thermally stable and power positive.”
“I’m very happy.”
“Our first trajectory correction maneuver will be in about two weeks,” Theisinger added.
“We’ll do instrument checkouts in the next several weeks and continue with thorough preparations for the landing on Mars and operations on the surface.”
Curiosity is a 900 kg (2000 pound) behemoth. She measures 3 meters (10 ft) in length and is nearly twice the size and five times as heavy as Spirit and Opportunity, NASA’s prior set of twin Martian robots.
NASA was only given enough money to build 1 rover this time.
“We are ready to go for landing on the surface of Mars, and we couldn’t be happier,” said John Grotzinger, Mars Science Laboratory Project Scientist from the California Institute of Technology at the briefing. “I think this mission will be a great one. It is an important next step in NASA’s overall goal to address the issue of life in the universe.”
Pete Theisinger, Mars Science Laboratory Project Manager from the Jet Propulsion Laboratory in California and John Grotzinger, Mars Science Laboratory Project Scientist from the California Institute of Technology at the Nov. 26 post-launch media briefing at the Kennedy Space Center (KSC), pose with model of Atlas V rocket. Credit: Ken Kremer
Curiosity is equipped with a powerful 75 kilogram (165 pounds) array of 10 state-of-the-art science instruments weighing 15 times more than its predecessor’s science payloads.
Curiosity rover launches to Mars atop an Atlas V rocket on Nov. 26 from Cape Canaveral, Florida. Credit: Mike Killian/Zero-G News
A drill and scoop located at the end of the robotic arm will gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into analytical laboratory instruments inside the rover. A laser will zap rocks to determine elemental composition.
“We are not a life detection mission.”
“It is important to distinguish that as an intermediate mission between the Mars Exploration Rovers, which was the search for water, and future missions, which may undertake life detection.”
“Our mission is about looking for ancient habitable environments – a time on Mars which is very different from the conditions on Mars today.”
“The promise of Mars Science Laboratory, assuming that all things behave nominally, is we can deliver to you a history of formerly, potentially habitable environments on Mars,” Grotzinger said at the briefing. “But the expectation that we’re going to find organic carbon, that’s the hope of Mars Science Laboratory. It’s a long shot, but we’re going to try.”
Today’s liftoff was the culmination of about 10 years of efforts by the more than 250 science team members and the diligent work of thousands more researchers, engineers and technicians spread around numerous locations across the United States and NASA’s international partners including Canada, Germany, Russia, Spain and France.
“Scientists chose the site they wanted to go to for the first time in history, because of the precision engineering landing system. We are going to the very best place we could find, exactly where we want to go.”
“I can’t wait to get on the ground,” said Grotzinger.
John Grotzinger, Mars Science Laboratory Project Scientist from the California Institute of Technology and Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters at the post launch briefing for reporters at KSC. Credit: Ken Kremer
Complete Coverage of Curiosity – NASA’s Next Mars Rover launched 26 Nov. 2011
Read continuing features about Curiosity by Ken Kremer starting here:
DEM L71 - a Type 1a supernova remnant. Analysis a the outer shockwave and inner ejecta indicate the explosion contains a mass not much exceeding 1 solar mass, which contains a high iron to silicon/ oxygen ratio. This all very suggestive that the progenitor star was a compact white dwarf. Apart from that the steps leading up to the explosion are a mystery (Credit: NASA/Chandra)
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With so much of our current understanding of the universe based on Type 1a supernovae data, a good deal of current research is focused upon just how standard these supposed standard candles are. To date, the weight of analysis seems reassuring – apart from a few outliers, the supernovae do all seem very standard and predictable.
However, some researchers have come at this issue from a different perspective by considering the characteristics of the progenitor stars that produce Type 1a supernovae. We know very little about these stars. Sure, they are white dwarfs that explode after accumulating extra mass – but just how this outcome is reached remains a mystery.
Indeed, the final stages preceding an explosion have never been definitively observed and we cannot readily point to any stars as likely candidates on a pathway towards Type Ia-ness. In comparison, identifying stars that are expected to explode as core collapse supernovae (Types Ib, Ic or II) is easy – core collapse should be the destiny of any star bigger than 9 solar masses.
Popular theory has it that a Type 1a progenitor is a white dwarf star in a binary system that draws material off its binary companion until the white dwarf reaches the Chandrasekhar limit of 1.4 solar masses. As the already compressed mass of predominantly carbon and oxygen is compressed further, carbon fusion is rapidly initiated throughout the star. This is such an energetic process that the comparatively small star’s self-gravity cannot contain it – and the star blows itself to bits.
Surprisingly, the white dwarf merger scenario seems the more likely cause of Type 1a supernovae, based on current (though largely circumstantial) evidence (Credit: Bad Astronomy/Discovery).
But when you try to model the processes leading up to a white dwarf achieving 1.4 solar masses, it seems to require a lot of ‘fine tuning’. The rate of accretion of extra mass has to be just right – too fast a flow will result in a red giant scenario. This is because adding extra mass quickly will give the star enough self-gravity so that it can partially contain the fusion energy – meaning that it will expand rather than explode.
Theorists get around this problem by proposing that a stellar wind arising from the white dwarf moderates the rate of infalling material. This sounds promising, although to date studies of Type 1a remnant material have found no evidence of the dispersed ions that would be expected from a pre-existing stellar wind.
Furthermore, a Type 1a explosion within a binary should have a substantial impact on its companion star. But all searches for candidate surviving companions – which would presumably possess anomalous characteristics of velocity, rotation, composition or appearance – have been inconclusive to date.
An alternative model for the events that lead up to a Type 1a are that two white dwarfs are drawn together, inexorably inspiralling until one or the other achieves 1.4 solar masses. This is not a traditionally favoured model as the time required for two such comparatively small stars to inspiral and merge could be billions of years.
However, Maoz and Mannucci review recent attempts to model the rate of Type 1a supernovae within a set volume of space and then align this with the expected frequency of different progenitor scenarios. Assuming that between 3 to 10 % of all 3-8 solar mass stars eventually explode as Type 1a supernovae – this rate does favour the ‘when white dwarfs collide’ model over the ‘white dwarf in a binary’ model.
There is no immediate concern that this alternate formation process would affect the ‘standardness’ of a Type 1a explosion – it’s just not the finding that most people were expecting.
The Mars Science Laboratory is now on an 8.5 month trip to Mars! Watch the successful launch above, and our on-site team of Ken Kremer, Alan Walters, David Gonazales and Jason Rhian will provide all the launch details and more in subsequent, fact- and photo-filled articles.
Atlas V rocket and Curiosity Mars rover poised at Space Launch Complex 41 at Cape Canaveral, Florida. Curiosity is set to blast off to Mars on Nov. 26, 2011. Credit: Ken Kremer
[/caption]‘Mars Trek – Curiosity’s Search for Undiscovered Life’ has its galaxy wide premiere Saturday morning Nov. 26 at 10:02 a.m. EST – live on NASA TV.
NASA’s quest ‘In Search of Life’ takes a bold leap in less than 12 hours with the Nov. 26 blastoff of “Curiosity”, the most complex and scientifically advanced robotic explorer ever sent to survey the surface of another world. The 103 minute launch window closes at 11:45 a.m. EST.
Curiosity and the United Launch Alliance Atlas V rocket that will thrust her to the Red Planet are poised for liftoff after being rolled out to Space Launch Complex 41 around 8 a.m. this morning under the watchful eyes of ground crews, mission scientists, reporters and photographers.
Universe Today was there – reporting live on all the history making and thrilling events !
Launch day weather remains favorable, with only a 30 percent chance of conditions prohibiting liftoff, said Air Force meteorologists. A low cloud ceiling is the sole concern at this time.
NASA’s Curiosity Mars rover is encapsulated inside the 5 meter payload fairing and loaded atop the Atlas V rocket at Space Launch Complex 41 at Cape Canaveral. Credit: Ken Kremer
The 1.2 million pound booster was pushed 1800 feet along rail tracks by twin diesel powered trackmobiles from the prelaunch preparation and assembly gantry inside the Vertical Integration Facility out to launch pad 41 at Cape Canaveral Air Force Station.
The 197 foot tall booster is equipped with 4 strap on solid rocket motors and generates some 2 million pounds of liftoff thrust according to Vernon Thorp, Atlas Program manager for ULA.
Curiosity is NASA’s next Mars rover and also quite possibly the last US built Mars rover due to severe cuts to NASA planetary science budget.
After an eight and one half month and 354 million mile (570 million km) interplanetary journey, Curiosity will slam into the thin Martian atmosphere at 13,000 MPH and utilize an unprecedented rocket powered pinpoint landing system known as the Sky Crane to touch down with all six wheels deployed inside Gale Crater.
Gale Crater is 154 km (96 mi) in diameter and dominated by a layered mountain rising some 5 km (3 mi) above the crater floor which exhibits exposures of minerals that may have preserved evidence of past or present Martian life.
NASA’s Curiosity Mars rover is rolled out from the Vertical Integration Facility to Launch Pad 41 at Cape Canaveral. Credit: Ken Kremer
Curiosity is packed with 10 state-of-the-art science experiments that will search for organic molecules and clay minerals, potential markers for signs of Martian microbial life and habitable zones.
Atlas V and Curiosity poised at Space Launch Complex 41 at Cape Canaveral, Florida for liftoff to Mars on Nov. 26, 2011. Credit: David Gonzales/Mike Deep
Immediately after touchdown, the 1 ton rover will transmit telemetry so that engineers back on Earth can assess the rover’s status.
“When we first land we want to ascertain the integrity and health of the vehicle and look at the surrounding terrain, said Pete Theisinger, MSL project manager from the Jet Propulsion Laboratory in Pasadena, Calif., at the briefing.
“The rover’s mast will be deployed on the second day and we’ll get pictures.”
“Shortly thereafter we will begin our science investigations. The radiation (RAD) and subsurface hydrogen detection (DAN) instruments will start right away since they are passive.”
The rover will drive inside the first week.
“The cameras will be used to select targets. We will go up to the valuable targets. With the cameras and instruments we will determine which ones to sample” said Theisinger.
“Then we’ll deploy the arm which contains scientific equipment and collect samples with a percussion drill. The samples will be injected into the two science instruments for analysis that are located on the rover.”
“The SAM and ChemMin instruments will look for organic molecules and isotope ratios as well as identify and quantify the minerals in the rock and soil samples. It could be up to 2 to 3 months before we take the first samples,” explained Theisinger.
MSL is powered by a nuclear battery and is expected to operate for a minimum of one Martian year, equivalent to 687 days on Earth. NASA hopes the 6 foot tall rover will last alot longer.
Curiosity atop Atlas V poised at Space Launch Complex 41 at Cape Canaveral, Florida for liftoff to Mars on Nov. 26, 2011. Credit: David Gonzales/Mike Deep
Complete Coverage of Curiosity – NASA’s Next Mars Rover launching 26 Nov. 2011
Read continuing features about Curiosity by Ken Kremer starting here:
Before you consider buying expensive equipment for viewing the wonders of the night sky, binoculars are one piece of equipment every amateur astronomer should have.
Many beginners to astronomy (especially around the holiday period) are sometimes dead-set on getting a telescope, but many aren’t aware that a good pair of binoculars can outperform many entry level telescopes for a similar cost, or much less.
Binoculars are simplicity in themselves — maintenance free, instantly available for use and very versatile, as they can be used for daytime, or “terrestrial viewing” just as well. It is difficult to say the same for with most telescopes.
Go into any photographic store, or website that sells binoculars and you will be met with literally hundreds of different makes, types and sizes – confusing for the beginner, but with a few pointers it can be easy to choose.
Credit: astronomybinoculars.com
So how do you choose a pair of binoculars that will give good results with astronomy?
When choosing binoculars for astronomy, the only variables you need to think about are size of the optics and weight.
Too small and they won’t be powerful enough or let enough light in; too big and heavy means they are almost impossible to use without a support or tripod. Beginners need to find a pair of binoculars which are just right.
The key is to get as much light into the binoculars as possible without making them too heavy. This will give sharp views and comfort when used.
Size and weight come hand in hand, the more light gathered, the heavier the binoculars will be.
All binoculars are measured or rated by two numbers, for example: 10 X 25 or 15 X 70. The first number is the magnification and the second number is the “objective diameter” which is the diameter of the objective lens and this determines how much light can be gathered to form an image.
Credit: Halfblue Wikipedia
The second number or objective diameter is the most important one to consider when buying binoculars for astronomy, as you need to gather as much light as possible.
As a rule of thumb, binoculars with an objective diameter of 50mm or more are more suited to astronomy than smaller “terrestrial” binoculars. In many cases a larger objective also gives better eye relief (larger exit pupil) making the binoculars much more comfortable to use.
For the beginner or general user, don’t go too big with the objective diameter as you are also making the binoculars physically larger and heavier. Large binoculars are fantastic, but — again — almost impossible to keep steady without a support or tripod.
Celestron Skymaster 15 X 70 Binoculars
Good sizes of binoculars for astronomy start at around or just under 10 X 50 and can go up to 20 X 80, but any larger and they will need to be supported when using them. Some very good supported binoculars have objective diameters of more than 100mm. Theses are fantastic, but not as portable as their smaller counterparts.
Binoculars are one of the most important items a new or seasoned astronomer can buy. They are inexpensive, easy to choose, use and will last a very long time.
Galaxy Cluster MACS J0329.6-0211 lenses several background galaxies including a distant dwarf galaxy. CREDIT: A. Zitrin, et al.
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Gravitational lensing is a powerful tool for astronomers that allows them to explore distant galaxies in far more detail than would otherwise be allowed. Without this technique, galaxies at the edge of the visible universe are little more than tiny blobs of light, but when magnified dozens of times by foreground clusters, astronomers are able to explore the internal structural properties more directly.
Recently, astronomers at the University of Heidelberg discovered a gravitational lensed galaxy that ranked among the most distant ever seen. Although there’s a few that beat this one out in distance, this one is remarkable for being a rare quadruple lens.
The images for this remarkable discovery were taken using the Hubble Space Telescope in August and October of this year, using a total of 16 different colored filters as well as additional data from the Spitzer infrared telescope. The foreground cluster, MACS J0329.6-0211, is some 4.6 billion light years distant. In the above image, the background galaxy has been split into four images, labelled by the red ovals and marked as 1.1 – 1.4. They are enlarged in the upper right.
Assuming that the mass of the foreground cluster is concentrated around the galaxies that were visible, the team attempted to reverse the effects the cluster would have on the distant galaxy, which would reverse the distortions. The restored image, also corrected for redshift, is shown in the lower box in the upper right corner.
After correcting for these distortions, the team estimated that the total mass of the distant galaxy is only a few billion times the mass of the Sun. In comparison, the Large Magellanic Cloud, a dwarf satellite to our own galaxy, is roughly ten billion solar masses. The overall size of the galaxy was determined to be small as well. These conclusions fit well with expectations of galaxies in the early universe which predict that the large galaxies in today’s universe were built from the combination of many smaller galaxies like this one in the distant past.
The galaxy also conforms to expectations regarding the amount of heavy elements which is significantly lower than stars like the Sun. This lack of heavy elements means that there should be little in the way of dust grains. Such dust tends to be a strong block of shorter wavelengths of light such as ultraviolet and blue. Its absence helps give the galaxy its blue tint.
Star formation is also high in the galaxy. The rate at which they predict new stars are being born is somewhat higher than in other galaxies discovered around the same distance, but the presence of brighter clumps in the restored image suggest the galaxy may be undergoing some interactions, driving the formation of new stars.
Amateur astronomer Rolf Wahl Olsen from New Zealand shared an image with Universe Today, and it is perhaps the first image of another solar system taken by an amateur. The image above is Olsen’s image of the protoplanetary disc around Beta Pictoris.
“For the last couple of years I have been wondering if it was possible for amateurs to capture this special target but have never come across any such images,” Olsen wrote in an email. “I must say it feels really special to have actually captured this.”
Olsen said he has been fascinated by professional images of Beta Pictoris since seeing the first one in taken in 1984.
Beta Pictoris and the protoplanetary disc of debris and dust that is orbiting the star is 63.4 light years away from Earth. This is a very young system thought to be only around 12 million years old and astronomers think this is essentially how our own Solar System must have formed some 4.5 billion years ago. The disc is seen edge-on from our perspective and appears in professional images as thin wedges or lines protruding radially from the central star in opposite directions.
“The main difficulty in imaging this system is the overwhelming glare from Beta Pictoris itself which completely drowns out the dust disc that is circling very close to the star,” Olsen said.
Images of the disc taken by the Hubble Space Telescope, and from big observatories, are usually made by physically blocking out the glare of Beta Pictoris itself within the optical path.
“I then realised that it might not be entirely impossible to also record this object with my own equipment,” Olsen said. “So now that Beta Pictoris has risen to a favorable position in this year’s evening sky I decided to have a go at it the other day.”
He followed the technique described in the paper, which basically consists of imaging Beta and then taking another image of a similar reference star under the same conditions. The two images are subtracted from each other to eliminate the stellar glare, and the dust disc should then hopefully reveal itself.
“First I collected 55 images of Beta Pictoris at 30 seconds each,” Olsen said. “The dust disc is most prominent in IR so ideally a better result would be expected with the use of an IR pass filter. Since I only have a traditional IR/UV block filter I just imaged without any filter, to at least get as much IR light through as possible.”
The next step was to capture a similar image of a reference star under the same conditions. Olsen did as the paper suggested and used Alpha Pictoris, a star that is of nearly the same spectral type (A7IV compared to Beta’s A6V) and is also close enough to Beta in the sky so that the change in telescope orientation should not affect the diffraction pattern. However, since the two stars have different magnitudes he needed to calculate how long to expose Alpha for in order to get a similar image which he could subtract from the Beta image.
Some quick math:
The magnitude difference between the stars is 3.86(Beta) – 3.30(Alpha) = 0.56
Due to the logarithmic nature of the magnitude scale we know that a difference of 1 magnitude equals a brightness ratio of 2.512. Therefore 2.512 to the power of the numerical magnitude difference then equals the variation in brightness.
2.512^0.56 = 1.67, so it appears Alpha is 1.67 times brighter than Beta. This means that exposure for Alpha should be 1/1.67 = 0.597x that of Beta. I took the liberty of using 0.6x for simplicity’s sake…
“So I collected 55 images of 18 seconds (30 x 0.6) for Alpha,” Olsen said. “Both sets of images were stacked separately in Registax and I then imported these into Photoshop, layered Alpha in ‘Difference’ mode on top of Beta and flattened the result. This produces a very dark image (which it should!) apart from the different background stars. But after some curves adjustment I was able to see clear signs of the actual dust disc protruding on both sides from the glare of the star. I was very happy to conclude that the position angle with regards to the background stars matched the official images exactly.”
Olsen said he was disappointed with the raw “Difference” image so to produce a more natural looking result, he took the original stacked Beta image and then blended in the central parts from the Difference image that showed the dust disc.
“I decided to also keep the black spot of the central glare from the Difference image since the contrast with the protruding disc seems better this way,” Olsen said.
Olsen is encouraging others amateur astrophotographers to try this, and see if they can do even better.
“I’m sure this can be done much better with a higher quality camera, but at least here it is,” he said. And I’m personally extremely happy and proud of having achieved this. I hope you enjoy the view as much as I did!”
If any other amateur astronomers have attempted to image a disk around another star, we’d love to hear about it and see the results.
In the future, planetary protection (where we ensure that missions do not contaminate other words with Earth-borne organisms) will be especially important. Credit: NASA, JPL-Caltech
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NASA’s Curiosity Mars rover, the most technologically complex and scientifically capable robot built by humans to explore the surface of another celestial body, is poised to liftoff on Nov. 26 and will enable a quantum leap in mankind’s pursuit of Martian microbes and signatures of life beyond Earth.
“The Mars Science Lab and the rover Curiosity is ‘locked and loaded’, ready for final countdown on Saturday’s launch to Mars,” said Colleen Hartman, assistant associate administrator in NASA’s Science Mission Directorate, at a pre-launch media briefing at the Kennedy Space Center (KSC).
The $2.5 Billion robotic explorer remains on track for an on time liftoff aboard a United Launch Alliance Atlas V rocket at 10:02 a.m. on Nov. 26 from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida.
Atlas V rocket at Space Launch Complex 41 at Cape Canaveral, Florida. An Atlas V rocket similar to this one utilized in August 2011 for NASAS’s Juno Jupiter Orbiter will blast Curiosity to Mars on Nov. 26, 2011 from Florida. Credit: Ken Kremer
NASA managers and spacecraft contractors gave the “Go-Ahead” for proceeding towards Saturday’s launch at the Launch Readiness Review on Wednesday, Nov. 23. The next milestone is to move the Atlas V rocket 1800 ft. from its preparation and assembly gantry inside the Vertical Integration Facility at the Cape.
“We plan on rolling the vehicle out of the Vertical Integration Facility on Friday morning [Nov. 25] ,” said NASA Launch Director Omar Baez at the briefing. “We should be on the way to the pad by 8 a.m.”
The launch window on Nov. 26 is open until 11:14 a.m. and the current weather prognosis is favorable with chances rated at 70 percent “GO”.
“The final launch rehearsal – using the real vehicle ! – went perfectly, said NASA Mars manager Rob Manning, in an exclusive interview with Universe Today. Manning is the Curiosity Chief Engineer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
“I was happy.”
“The folks at KSCs Payload Handling Facility and at JPL’s cruise mission support area (CMSA) – normally a boisterous bunch – worked quietly and professionally thru to T-4 minutes and a simulated fake hold followed by a restart and a recycle (shut down) due to a sail boat floating too close to the range,” Manning told me.
Curiosity rover - Engineering support team working at consoles at JPL. Credit: Rob Manning
Readers may recall that NASA’s JUNO Jupiter orbiter launch in August was delayed by an hour when an errant boat sailed into the Atlantic Ocean exclusion zone.
“This rover, Curiosity rover, is really a rover on steroids. It’s an order of magnitude more capable than anything we have ever launched to any planet in the solar system,” said Hartman.
“It will go longer, it will discover more than we can possibly imagine.”
Curiosity rover explores inside Gale Crater after landing in August 2012. The mast, or rover's "head," rises to about 2.1 meters (6.9 feet) above ground level, about as tall as a basketball player. Credit: NASA, JPL-Caltech
Curiosity is locked atop the powerful Alliance Atlas V rocket that will propel the 1 ton behemoth on an eight and one half month interplanetary cruise from the alligator filled swamps of the Florida Space Coast to a layered mountain inside Gale Crater on Mars where liquid water once flowed and Martian microbes may once have thrived.
Curiosity is loaded inside the largest aeroshell ever built and that will shield her from the extreme temperatures and intense buffeting friction she’ll suffer while plummeting into the Martian atmosphere at 13,000 MPH (5,900 m/s) upon arrival at the Red Planet in August 2012.
The Curiosity Mars Science Lab (MSL) rover is the most ambitious mission ever sent to Mars and is equipped with a powerful 75 kilogram (165 pounds) array of 10 state-of-the-art science instruments weighing 15 times as much as its predecessor’s science payloads.
Curiosity measures 3 meters (10 ft) in length and weighs 900 kg (2000 pounds), nearly twice the size and five times as heavy as NASA’s prior set of twin robogirls – Spirit and Opportunity.
The science team selected Gale crater as the landing site because it exhibits exposures of clays and hydrated sulfate minerals that formed in the presence of liquid water billions of years ago, indicating a wet history on ancient Mars that could potentially support the genesis of microbial life forms. Water is an essential prerequisite for life as we know it.
Gale Crater is 154 km (96 mi) in diameter and dominated by a layered mountain rising some 5 km (3 mi) above the crater floor.
Oblique View of Gale Crater, Mars, with Vertical Exaggeration
Gale Crater, where the rover Curiosity of NASA's Mars Science Laboratory mission will land in August 2012, contains a mountain rising from the crater floor. This oblique view of Gale Crater, looking toward the southeast, is an artist's impression using two-fold vertical exaggeration to emphasize the area's topography. Curiosity's landing site is on the crater floor northeast of the mountain. The crater's diameter is 96 miles (154 kilometers). The image combines elevation data from the High Resolution Stereo Camera on the European Space Agency's Mars Express orbiter, image data from the Context Camera on NASA's Mars Reconnaissance Orbiter, and color information from Viking Orbiter imagery.
Credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
The car sized rover is being targeted with a first of its kind precision rocket powered descent system to touchdown inside a landing ellipse some 20 by 25 kilometers (12.4 miles by 15.5 miles) wide and astride the towering mountain at a location in the northern region of Gale.
Curiosity’s goal is to search the crater floor and nearby mountain – half the height of Mt. Everest – for the ingredients of life, including water and the organic molecules that we are all composed of.
The robot will deploy its 7 foot long arm to collect soil and rock samples to assess their composition and determine if any organic materials are present – organics have not previously been detected on Mars.
Curiosity will also vaporize rocks with a laser to determine which elements are present, look for subsurface water in the form of hydrogen, and assess the weather and radiation environments
“After the rocket powered descent, the Sky-Crane maneuver deploys the rover and we land on the mobility system, said Pete Theisinger, MSL project manager from the Jet Propulsion Laboratory in Pasadena, Calif., at the briefing.
The rover will rover about 20 kilometers in the first year. Curiosity has no life limiting constraints. The longevity depends on the health of the rovers components and instruments.
“We’ve had our normal challenges and hiccups that we have in these kinds of major operations, but things have gone extremely smoothly and we’re fully prepared to go on Saturday morning. We hope that the weather cooperates, said Theisinger
Missions to Mars are exceedingly difficult and have been a death trap for many orbiters and landers.
“Mars really is the Bermuda Triangle of the solar system,” said Hartman. “It’s the ‘death planet,’ and the United States of America is the only nation in the world that has ever landed and driven robotic explorers on the surface of Mars. And now we’re set to do it again.”
Complete Coverage of Curiosity – NASA’s Next Mars Rover launching 26 Nov. 2011
Read continuing features about Curiosity by Ken Kremer starting here:
An artist impression of an exomoon orbiting an exoplanet, could the exoplanet's wobble help astronomers? (Andy McLatchie)
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In an article earlier this month, I discussed the potential for discovering moons orbiting extrasolar planets. I’d used an image of an exoplant system with rings, prompting one reader to ask if those would be possible to detect. Apparently he wasn’t the only person wondering. A new paper looks more at exomoons and explores exoring systems.
The idea of detecting rings around distant planets dates back to at least 2004. Then, Barnes & Fortney suggested that rings would be potentially detectable from the eclipse they would cause if the photometric precision were as one part in ten-thousand. This is a big challenge, but one that’s more than met by telescopes like Kepler today. But for this to be possible, the rings needed to block the most light possible, meaning that they would have to be viewed face on, instead of edge on.
Fortunately, a study this year by Schlichting & Chang demonstrated that, even if the planet’s spin is aligned with the plane of orbit, it’s quite possible that the rings will be significantly warped due to gravitational interactions with the star.
So it should be possible, but what do astronomers need to look for?
The new paper attempts to answer this question by simulating light curves for a hypothetical ringed exoplanet. The first result is that the extra area of the star’s surface covered by the rings reduces the light detected. However, this is difficult to disentangle from the effects of simply having a larger planet that blocks the light.
Simulated light curve for exoplanet system with rings vs model lacking rings. Credit: Tusnski & Valio
A second effect is based on the shape of the light curve (a graph of the brightness as a function of time) as the planet begins and ends the transit. In short, the semi-transparent nature of the rings makes the drop in brightness softer, rounding off the edges of the light curve. When modeled against a planet that lacked rings, this would be readily detectable for an instrument like Kepler.
With such precision, the team suggests that Kepler should be more than capable of detecting a ring system similar in size and nature to those of Saturn. However, other transit finding telescopes, such as CoRoT, would mistake the rings for a slightly larger planet.
In the future, the team plans to take their model and reexamine data from Kepler and CoRoT to search for both rings and moons.
