We’ve found hundreds of planets outside the solar system, but taking a picture of one is still something quite special. The light of the parent star tends to greatly overwhelm the faint light of the alien planet. (So usually we learn about planets by tracking the effects each planet has on its star, like dimming light when it passes in front or making the star slightly wobble.)
This picture (above) shows HD95086 b, which astronomers believe is one of only about a dozen exoplanets ever imaged. It’s 300 light-years from Earth. The planet candidate is about four to five times the mass of Jupiter and orbiting a very young star that is probably only 10 million to 17 million years old. That’s a baby compared to our own solar system, estimated at 4.5 billion years old.
We still have a lot to learn about this object (and the observations from the Very Large Telescope will need to be confirmed independently), but so far astronomers say they figure that planet formed in the gas and dust surrounding star HD 95086. But the planet is actually very far away from the star now, about twice the distance as the Sun-Neptune orbital span in our own solar system.
“Its current location raises questions about its formation process,” stated team member Anne-Marie Lagrange, who is with the Grenoble Institute of Planetology and Astrophysics in France.
“It either grew by assembling the rocks that form the solid core and then slowly accumulated gas from the environment to form the heavy atmosphere, or started forming from a gaseous clump that arose from gravitational instabilities in the disc.
“Interactions between the planet and the disc itself,” she added, “or with other planets may have also moved the planet from where it was born.”
Astronomers estimate the planet candidate has a surface temperature of 1,292 degrees Fahrenheit (700 degrees Celsius), which could allow water vapor or methane to stick around in the atmosphere. It will take more VLT observations to figure this out, though.
The results from this study will be published in Astrophysical Journal Letters. The paper is also available on prepublishing site Arxiv.
New measurements of the energetic space radiation environment present in interplanetary space taken by NASA’s Curiosity rover confirm what has long been suspected – that lengthy years long voyages by astronauts to deep space destinations like Mars will expose the crews to high levels of radiation that – left unchecked – would be harmful to their health and increase their chances of developing fatal cancers.
Although the data confirm what scientists had suspected, it’s equally important to state that the space radiation data are not ‘show stoppers” for human deep space voyages to the Red Planet and other destinations because there are a multitude of counter measures- like increased shielding and more powerful propulsion – that NASA and the world’s space agencies can and must implement to reduce and mitigate the dangerous health effects of radiation on human travelers.
The new radiation data was released at a NASA media briefing on May 30 and published in the journal Science on May 31.
Indeed the new measurements collected by Curiosity’s Radiation Assessment Detector (RAD) instrument during her 253-day, 560-million- kilometer journey enroute to the Red Planet in 2011 and 2012 will provide important insights to allow NASA to start designing systems for safely conducting future human missions to Mars.
“NASA wants to send astronauts to Mars in the 2030’s,” Chris Moore, NASA’s deputy director of Advanced Exploration Systems NASA HQ, said to reporters at the media briefing.
“The Human Spaceflight and Planetary Science Divisions at NASA are working together to get the data needed for human astronauts. RAD is perfect to collect the data for that,” said Moore.
The RAD data indicate that astronauts would be exposed to radiation levels that would exceed the career limit levels set by NASA during a more than year long voyage to Mars and back using current propulsion systems, said Eddie Semones, spaceflight radiation health officer at the Johnson Space Center.
NASA’s Humans to Mars planning follows initiatives outlined by President Obama.
“As this nation strives to reach an asteroid and Mars in our lifetimes, we’re working to solve every puzzle nature poses to keep astronauts safe so they can explore the unknown and return home,” said William Gerstenmaier, NASA’s associate administrator for human exploration and operations in Washington, in a statement.
The International Space Station already in low Earth orbit and the Orion crew capsule under development will serve as very useful platforms to conduct real life experiments on resolving the health risks posed by long term exposure to space radiation.
“We learn more about the human body’s ability to adapt to space every day aboard the International Space Station, said Gerstenmaier. “As we build the Orion spacecraft and Space Launch System rocket to carry and shelter us in deep space, we’ll continue to make the advances we need in life sciences to reduce risks for our explorers. Curiosity’s RAD instrument is giving us critical data we need so that we humans, like the rover, can dare mighty things to reach the Red Planet.”
RAD was the first instrument to collect radiation measurements during the cruise phase to the Red Planet. It is mounted on the top deck of the Curiosity rover.
“Although RAD’s objective is to characterize the radiation environment on the surface of Mars, it’s also good for the cruise phase,” Don Hassler, RAD Principal Investigator at the Southwest Research Institute (SWRI) told reporters.
“Since Orion and MSL are similar sized RAD is ideal for collecting the data.”
Hassler explained that RAD measures two types of radiation that pose health risks to astronauts. First, the steady stream of low dose galactic cosmic rays (GCRs), and second the short-term and unpredictable exposures to solar energetic particles (SEPs) arising from solar flares and coronal mass ejections (CME’s).
Radiation exposure is known to increase a person’s risk of suffering fatal cancer.
Exposure is measured in units of Sievert (Sv) or milliSievert (one one-thousandth Sv). Being exposed to a dose of 1 Sievert (Sv) over time results in a five percent increased risk of developing cancer.
NASA’s current regulations limit the potential for increased cancer risk to 3 percent for astronauts currently working on the ISS in low-Earth orbit.
RAD determined that the Curiosity rover was exposed to an average of 1.8 milliSieverts per day during the 8.5 month cruise to Mars, due mostly to Galactic Cosmic Rays, said Cary Zeitlin, SWRI Principal Scientist for MSL,at the briefing. “Solar particles only accounted for about 3 to 5 percent of that.”
During a typical 6 month cruise to Mars the astronaut crews would be exposed to 330 millisieverts. That is more than 3 times the typical 6 month exposure of astronauts aboard the ISS which amounts to about 100 millisieverts. See graphic above.
“The 360 day interplanetary round trip exposure would be 660 millisieverts based on chemical propulsion methods,” Zeitlin told Universe Today. “A 500 day mission would increase that to 900 millisieverts.”
By comparison, the average annual exposure for a typical person in the US from all radiation sources is less than 10 millisieverts.
The Earth’s magnetic field provides partial radiation shielding for the ISS astronauts living in low-Earth orbit.
“In terms of accumulated dose, it’s like getting a whole-body CT scan once every five or six days,” says Zeitlin.
And that round trip dose of 660 millisieverts doesn’t even include the astronauts surface stay on Mars – which would significantly raise the total exposure count. But luckily for the crew the surface radiation is less.
“The radiation environment on the surface of Mars is about half that in deep space since its modified by the atmosphere,” Hassler told Universe Today. “We will publish the surface data in a few months.”
NASA will need to decide whether to reassess the acceptable career limits for astronauts exposure to radiation from galactic cosmic rays and solar particle events during long duration deep space journeys.
Panoramic view of Yellowknife Bay basin back dropped by Mount Sharp shows the location of the first two drill sites – John Klein & Cumberland – targeted by NASA’s Curiosity Mars rover and the RAD radiation detector which took the first deep space measurements of harmful space radiation during the cruise phase to Mars in 2011 and 2012 . Curiosity accomplished historic 1st drilling into Martian rock at John Klein outcrop on Feb 8, 2013 (Sol 182) near where the robotic arm is touching the surface. This week the rover scooted about 9 feet to the right to Cumberland (right of center) for 2nd drill campaign on May 19, 2013 (Sol 279). Credit: NASA/JPL-Caltech/Ken Kremer – kenkremer.com/Marco Di Lorenzo
And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013
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Learn more about Conjunctions, Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations
June 4: “Send your Name to Mars on MAVEN” and “CIBER Astro Sat, LADEE Lunar & Antares Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8:30 PM
Saturn’s F ring is certainly a curious structure. Orbiting the giant planet 82,000 kilometers above its equatorial cloud tops, the F ring is a ropy, twisted belt of bright ice particles anywhere from 30-500 km wide. It can appear as a solid band or a series of braided cords surrounded by a misty haze, and often exhibits clumps and streamers created by the gravitational influence of embedded moonlets or passing shepherd moons.
In the picture above, acquired by the Cassini spacecraft on Feb. 13, 2013 and released on May 27, we see a section of the F ring separated into long ropes and spanned by connecting bands of bright material — the “ladder” structure suggested in the title.
Scientists believe that interactions between the F ring and the moons Prometheus and Pandora cause the dynamic structure of the F ring. (Watch an animation of the F ring and shepherd moons here.)
Made of particles of water ice finer than cigarette smoke, the F ring orbits Saturn beyond the outer edge of the A ring across the expanse of the 2,600-km-wide Roche Division. In these images, Saturn and the main ring systems are off frame to the left.
This view looks toward the unilluminated side of the rings from about 32 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft’s narrow-angle camera (NAC).
The view was obtained at a distance of approximately 426,000 miles (686,000 kilometers) from Saturn and at a phase angle of 162 degrees. Image scale is 2 miles (4 kilometers) per pixel.
The next time that American astronauts launch to space from American soil it will surely be aboard one of the new commercially built “space taxis” currently under development by a trio of American aerospace firms – Boeing, SpaceX and Sierra Nevada Corp – enabled by seed money from NASA’s Commercial Crew Program (CCP).
Boeing has moved considerably closer towards regaining America’s lost capability to launch humans to space when the firm’s privately built CST-100 crew capsule achieved two key new milestones on the path to blastoff from Florida’s Space Coast.
The CST-100 capsule is designed to carry a crew of up to 7 astronauts on missions to low-Earth orbit (LEO) and the International Space Station (ISS) around the middle of this decade.
Boeing’s crew transporter will fly to space atop the venerable Atlas V rocket built by United Launch Alliance (ULA) from Launch Complex 41 on Cape Canaveral Air Force Station in Florida.
The Boeing and ULA teams recently completed the first wind tunnel tests of a 7 percent scale model of the integrated capsule and Atlas V rocket (photo above) as well as thrust tests of the modified Centaur upper stage.
The work is being done under the auspices of NASA’s Commercial Crew Integrated Capability (CCiCap) initiative, intended to make commercial human spaceflight services available for both US government and commercial customers, such as the proposed Bigelow Aerospace mini space station.
Since its maiden liftoff in 2002, the ULA Atlas V rocket has flawlessly launched numerous multi-billion dollar NASA planetary science missions like the CuriosityMars rover, Juno Jupiter orbiter and New Horizons mission to Pluto as well as a plethora of top secret Air Force spy satellites.
But the two stage Atlas V has never before been used to launch humans to space – therefore necessitating rigorous testing and upgrades to qualify the entire vehicle and both stages to meet stringent human rating requirements.
“The Centaur has a long and storied past of launching the agency’s most successful spacecraft to other worlds,” said Ed Mango, NASA’s CCP manager at the agency’s Kennedy Space Center in Florida. “Because it has never been used for human spaceflight before, these tests are critical to ensuring a smooth and safe performance for the crew members who will be riding atop the human-rated Atlas V.”
The combined scale model CST-100 capsule and complete Atlas V rocket were evaluated for two months of testing this spring inside an 11- foot diameter transonic wind tunnel at NASA’s Ames Research Center in Moffett Field, Calif.
“The CST-100 and Atlas V, connected with the launch vehicle adaptor, performed exactly as expected and confirmed our expectations of how they will perform together in flight,” said John Mulholland, Boeing vice president and program manager for Commercial Programs.
Testing of the Centaur stage centered on characterizing the flow of liquid oxygen from the oxygen tank through the liquid oxygen-feed duct line into the pair of RL-10 engines where the propellant is mixed with liquid hydrogen and burned to create thrust to propel the CST-100 into orbit.
Boeing is aiming for an initial three day manned orbital test flight of the CST-100 during 2016, says Mulholland.
But that date is dependent on funding from NASA and could easily be delayed by the ongoing sequester which has slashed NASA’s and all Federal budgets.
Chris Ferguson, the commander of the final shuttle flight (STS-135) by Atlantis, is leading Boeing’s flight test effort.
Boeing has leased one of NASA’s Orbiter Processing Facility hangers (OPF-3) at the Kennedy Space Center (KSC) for the manufacturing and assembly of its CST-100 spacecraft.
Mulholland told me previously that Boeing will ‘cut metal’ soon. “Our first piece of flight design hardware will be delivered to KSC and OPF-3 around mid 2013.”
NASA’s CCP program is fostering the development of the CST-100 as well as the SpaceX Dragon and Sierra Nevada Dream Chaser to replace the crew capability of NASA’s space shuttle orbiters.
The Atlas V will also serve as the launcher for the Sierra Nevada Dream Chaser space taxi.
Since the forced retirement of NASA’s shuttle fleet in 2011, US and partner astronauts have been 100% reliant on the Russians to hitch a ride to the ISS aboard the Soyuz capsules – at a price tag exceeding $60 Million per seat.
Simultaneously on a parallel track NASA is developing the Orion crew capsule and SLS heavy lift booster to send humans to the Moon and deep space destinations including Asteroids and Mars.
And don’t forget to “Send Your Name to Mars” aboard NASA’s MAVEN orbiter- details here. Deadline: July 1, 2013
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Learn more about Conjunctions, Mars, Curiosity, Opportunity, MAVEN, LADEE and NASA missions at Ken’s upcoming lecture presentations:
June 4: “Send your Name to Mars” and “CIBER Astro Sat, LADEE Lunar & Antares ISS Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8:30 PM
Is time real or is it just an illusion of the human experience? An intriguing new book “Time Reborn” by theoretical physicist Lee Smolin discusses this concept. You can read our full review of this here, but we also have three free copies of this book to give away.
In order to be entered into the giveaway drawing, just put your email address into the box at the bottom of this post (where it says “Enter the Giveaway”) before Wednesday June 5, 2013. We’ll send you a confirmation email, so you’ll need to click that to be entered into the drawing.
If you’d like to purchase the book, you can find it on Amazon.
Time Reborn: From the Crisis of Physics to the Future of the Universe is one of those books intended to provoke discussion. Right from the first pages, author Lee Smolin — a Canadian theoretical physicist who also teaches philosophy — puts forward a position: time is real, and not an illusion of the human experience (as other physicists try to argue).
Smolin, in fact, uses that concept of time as a basis for human free will. If time is real, he writes, this is the result: “Novelty is real. We can create, with our imagination, outcomes not computable from knowledge of the present.”
Physics as philosophy. A powerful statement to make in the opening parts of the book. The only challenge is understanding the rest of it.
Smolin advertises his book as open to the general reader who has no background in physics or mathematics, promising that there aren’t even equations to worry about. He also breaks up the involved explanations with wry observations of fatherhood, or by bringing up anecdotes from his past.
It works, but you need to be patient. Theoretical physics is so far outside of the everyday that at times it took me (with education focusing on journalism and space policy, admittedly) two or three readings of the same passage to understand what was going on.
But as I took my time, a whole world opened up to me.
I found myself understanding more about Einstein’s special and general relativity than I did in readings during high school and university. The book also made me think differently about cosmology (the nature of the universe), especially in relation to biological laws.
While the book is enjoyable, it is probably best not to read it in isolation as it is a positional one — a book that gathers information scientifically and analytically, to be sure, but one that does not have a neutral point of view to the conclusions.
We’d recommend picking up other books such as the classic A Brief History of Time (by physicist Stephen Hawking) to learn more about the universe, and how other scientists see time work.
Since Asteroid 1998 QE2 has a name which evokes cruise ships, astrophysicist Rhys Taylor has created this wonderful video comparing the two QE2s. He also has more information on his great blog, Physicists of the Caribbean.
The moon’s gravity has been a headache ever since the Apollo era. Areas of “mass concentration” or mascons, discovered in 1968, affected spacecraft orbits and made landing on Earth’s neighbor a tricky challenge.
The phenomenon has puzzled scientists, but new data shows that mascons might have come to be after asteroids or comets hit the moon a long time ago.
For nine months last year, until their mission ended with a deliberate crash on a moon mountain, twin washing-machine sized spacecraft Ebb and Flow circled the planet. Their work was known as the GRAIL mission (also known as Gravity Recovery and Interior Laboratory.) As they orbited together, gravity changes in the moon below them slightly changed their distances to each other — sometimes closer, sometimes further.
This allowed scientists to map out the mascons to high precision once they combined that information with computer models of big asteroid impacts as well as how craters on the moon evolved.
Mascons, which are invisible on the surface but appear in gravity maps as a sort of bulls-eye, arise “as a natural consequence of crater excavation, collapse and cooling following an impact,” NASA stated.
The center of the bulls-eye has stronger gravity, with a ring of weaker gravity surrounding the bulls-eye, and then another ring of strong gravity surrounding the bulls-eye and inner ring.
“GRAIL data confirm that lunar mascons were generated when large asteroids or comets impacted the ancient moon, when its interior was much hotter than it is now,” stated Jay Melosh, lead researcher and a GRAIL co-investigator at Purdue University.
“We believe the data from GRAIL show how the moon’s light crust and dense mantle combined with the shock of a large impact to create the distinctive pattern of density anomalies that we recognize as mascons.”
What’s more, researchers expect they’ll be able to apply that understanding to Mercury and Mars, as mascons were also discovered on those terrestrial planets.
The findings appeared in the May 30 edition of Science. You can read the entire article here.
“That’s one small step for man… one giant leap for mankind.” And with those famous words astronaut Neil A. Armstrong awed the entire world on July 21, 1969, becoming the first human to set a booted foot upon a world other than our own. But the historic statement itself has caused no small bit of confusion and controversy over the years, from whether Armstrong came up with it on the spot (he didn’t) to what he actually said… small step for “man?” Where’s the “a?”
Although some have said that the article was left out or cut off (and admittedly it sure sounds that way to me) it turns out it’s probably been there the whole time, hidden behind Neil’s native Ohio accent.
According to a team of speech scientists and psychologists from Michigan State University (MSU) in East Lansing and The Ohio State University (OSU) in Columbus, it is entirely possible that Armstrong said what he had always claimed — though evidence indicates that most people are likely to hear “for man” instead of “for a man” on the Apollo 11 broadcast recordings.
By studying how speakers from Armstrong’s native central Ohio pronounce “for” and “for a,” the team’s results suggest that his “a” was acoustically blended into his “for.”
“Prior acoustic analyses of Neil Armstrong’s recording have established well that if the word ‘a’ was spoken, it was very short and was fully blended acoustically with the preceding word,” says Laura Dilley of Michigan State University. “If Armstrong actually did say ‘a,'” she continues, “it sounded something like ‘frrr(uh).'”
His blending of the two words, compounded with the poor sound quality of the television transmission, has made it difficult to corroborate his claim that the “a” is there.
“If Armstrong actually did say ‘a,’ it sounded something like ‘frrr(uh).'”
– Laura Dilley, Michigan State University
Dilley and her colleagues used a collection of recordings of conversational speech from 40 people raised in Columbus, Ohio, near Armstrong’s native town of Wapakoneta. Within this body of recordings, they found 191 cases of “for a.” They matched each of these to an instance of “for” as said by the same speaker and compared the relative duration. They also examined the duration of Armstrong’s “for (a”) from the lunar transmission.
The researchers found a large overlap between the relative duration of the “r” sound in “for” and “for a” using the Ohio speech data. The duration of the “frrr(uh)” in Armstrong’s recording was 0.127 seconds, which falls into the middle of this overlap. In other words, the researchers conclude, the lunar landing quote is highly compatible with either possible interpretation though it is probably slightly more likely to be perceived as “for” regardless of what Armstrong actually said.
Dilley says there may have been a “perfect storm of conditions” for the word “a” to have been spoken… but not heard.
“We’ve bolstered Neil Armstrong’s side of the story,” she says. “We feel we’ve partially vindicated him. But we’ll most likely never know for sure exactly what he said based on the acoustic information.”
(Personally, I feel that if the first man to walk on the Moon said he said “a,” then he said “a.”)