Nancy Atkinson, Author at Universe Today

December 4, 2008December 24, 2015 by Nancy Atkinson

Hubble Repair Mission Will Launch in May ’09

NASA announced Thursday that space shuttle Atlantis’ STS-125 mission to repair the Hubble Space Telescope is targeted to launch May 12, 2009. The mission, which was previously scheduled for October of this year was delayed when a data handling unit on the telescope failed. Since then, engineers have been working to prepare a 1970’s era spare unit for flight. They expect to be able to ship the spare, known as the Science Instrument Command and Data Handling System, to NASA’s Kennedy Space Center in Florida in spring 2009.

STS-125 is an 11-day flight featuring five spacewalks to extend Hubble’s life into the next decade by refurbishing and upgrading the telescope with state-of-the-art science instruments and swapping failed hardware. The crew consists of Scott Altman, commander; Greg Johnson, pilot; and mission specialists are veteran spacewalkers John Grunsfeld and Mike Massimino, and first-time space fliers Andrew Feustel, Michael Good and Megan McArthur.

The next space shuttle mission, STS-119, is scheduled for launch on Feb. 12, 2009, which will go to the International Space Station and bring up the S6 starboard truss segment and the final set of solar arrays. Another shuttle mission, STS-127 mission, is also targeted for launch in May 2009, but it’s possible that flight could slip. The Hubble mission will need another shuttle on standby for a rescue mission, should STS-125 encounter any problems (since its not going to the ISS, which would serve as a safe haven if a shuttle had any damage where it could not land safely).

Beyond that, STS-128 is targeted for August 2009, and STS-129 is targeted for November 2009. As always, all target launch dates are subject to change.

Source: NASA

December 4, 2008December 24, 2015 by Nancy Atkinson

Teddy Bears Go To Space

Two of the teddy bears imaged in Near Space. Credit: CU Spaceflight

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I don’t think this is what Iran has in mind about launching animals into space, but … you never know. Four teddy bears voyaged to the edge of space on Monday, December 1st via high altitude helium balloon. This was done as an experiment by a student organization at Cambridge University in England, along with a science club and community college. The bears were lifted to 30,085 meters above sea level, and the goal of the experiment was to determine which materials provided the best insulation against the -53 ° C temperatures experienced during the journey. Each of the bears wore a different space suit designed by 11-13 year-olds who were took part in the experiment. But the main goal of the endeavor was to give young students the opportunity to try their hand at a real mission in sending objects into space.

“We want to offer young people the opportunity to get involved in the space industry whilst still at school and show that real-life science is something that is open to everybody” says Iain Waugh, chief aeronautical engineer of student-run Cambridge University Spaceflight.

“High altitude balloon flights are a fantastic way of encouraging interest in science. They are easy to understand, and produce amazing results,” said Daniel Strange, treasurer of CU Spaceflight.

Prelaunch of the high altitude balloon. Credit: CU Spaceflight

The payload which carried the bears was designed by CU Spaceflight and contained several cameras, a flight computer, GPS and a radio. During the 2 hour and 9 minute flight, the radio broadcasted the location of the payload to a chase team on the ground. The team predicted the landing site using wind speed data and arrived in time to see the payload and teddy bears drift slowly back down to earth by parachute.

CU Spaceflight is a student-run society aiming to reduce the cost of sub-orbital spaceflight. They have launched several payloads to near space on high-altitude helium balloons and are currently designing a system to launch a rocket from a balloon platform to outer space for under £1000 per launch. They have run several outreach events and are currently holding the UK Space Challenge 2009, as part of the University of Cambridge’s 800th Anniversary. Twenty four teams of science students aged 14-18 are competing to design a scientific experiment that will be taken to near space on a high-altitude helium balloon.

More images of the flight.
More information about Cambridge University Spaceflight.

Source: CU Spaceflight

December 4, 2008December 24, 2015 by Nancy Atkinson

Students Find Exoplanet

Francis Vuijsje, Meta de Hoon, and Remco van der Burg (left to right), discovered an extrasolar planet that is larger than and about five times as massive as Jupiter and orbiting a fast-rotating hot star. Credit: Leiden Observatory

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Three undergraduate students doing a research project discovered an extrasolar planet. The planet is about five times as massive as Jupiter, not all that big as far as previously detected exoplanets go. This is also the first planet discovered orbiting a fast-rotating hot star. The students, Meta de Hoon, Remco van der Burg, and Francis Vuijsje from Leiden University in the Netherlands, were testing a method of investigating the light fluctuations of thousands of stars in the OGLE database in an automated way. The brightness of one of the stars was found to decrease for two hours every 2.5 days by about one percent. Follow-up observations, taken with ESO’s Very Large Telescope in Chile, confirmed that this phenomenon is caused by a planet passing in front of the star, blocking part of the starlight at regular intervals. “It is exciting not just to find a planet, but to find one as unusual as this one; it turns out to be the first planet discovered around a fast rotating star, and it’s also the hottest star found with a planet,” says Meta. “The computer needed more than a thousand hours to do all the calculations,” continues Remco.

According to Ignas Snellen, supervisor of the research project, the discovery was a complete surprise. “The project was actually meant to teach the students how to develop search algorithms. But they did so well that there was time to test their algorithm on a so far unexplored database. At some point they came into my office and showed me this light curve. I was completely taken aback!”

The planet is given the prosaic name OGLE2-TR-L9b. “But amongst ourselves we call it ReMeFra-1, after Remco, Meta, and myself,” says Francis.

Artist's impression of the planet OGLE-TR-L9b. Credit: ESO/H. Zodet

The planet was discovered by looking at the brightness variations of about 15,700 stars, which had been observed by the OGLE survey once or twice per night for about four years between 1997 and 2000. Because the data had been made public, they were a good test case for the students’ algorithm, who showed that for one of stars observed, OGLE-TR-L9, the variations could be due to a transit — the passage of a planet in front of its star. The team then used the GROND instrument on the 2.2 m telescope at ESO’s La Silla Observatory to follow up the observations and find out more about the star and the planet.

“But to make sure it was a planet and not a brown dwarf or a small star that was causing the brightness variations, we needed to resort to spectroscopy, and for this, we were glad we could use ESO’s Very Large Telescope,” says Snellen.

The planet, which is about five times as massive as Jupiter, circles its host star in about 2.5 days. It lies at only three percent of the Earth-Sun distance from its star, making it very hot and much larger than normal planets.

The spectroscopy also showed that the star is pretty hot — almost 7000 degrees, or 1200 degrees hotter than the Sun. It is the hottest star with a planet ever discovered, and it is rotating very fast. The radial velocity method — that was used to discover most extrasolar planets known — is less efficient on stars with these characteristics. “This makes this discovery even more interesting,” concludes Snellen.

Source: ESO

December 4, 2008December 24, 2015 by Nancy Atkinson

Iran to Launch Animals to Space

Kavoshgar rocket. Credit: Satnews Daily

Iran is planning to launch animals into space. According to Mohammed Ebrahimi from Iran’s Aerospace Research Institute, in the near future, the Kavoshgar-3 and -4 rockets will use animals as test passengers before they attempt a human mission. On November 26, Iran successfully launched its second space rocket, the Kavoshgar-2, which contained a space lab and a data-monitoring and processing unit. This Iranian rocket is fully capable of packing a small payload and then re-entering Earth’s atmosphere with a high degree of accuracy, according to reports. They will attempt two more test flights before trying to launch a working satellite into orbit with a larger rocket, the Safir-e Omid (or Ambassador of Peace) rocket. In August, Iran claimed they successfully launched a dummy satellite into space, which was refuted by the US. Officials from Iran insist the country’s space program is non-military in nature.

No information was released about what kinds of animals would be launched. On Nov. 26 Iranian state television reported that the Kavoshgar-2 completed its mission and returned to Earth via parachute after 40 minutes, and that the rocket had been designed and built by Iranian aerospace experts.

Much of Iran’s technological equipment derives from modified Chinese and North Korean technology. Earlier in November, Iran said it had also test-fired a new medium-range missile. Its 2,000-km (1,240-mile) range would be capable of reaching Western Europe. However, Iran denies that its long-range ballistic technology is linked to its atomic program.

The country is already under international pressure to give up its nuclear work, which it says is purely civilian.

Sources: Satnews Daily, BBC

December 4, 2008December 24, 2015 by Nancy Atkinson

Mars Science Laboratory Mission Delayed Two Years

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NASA’s Mars Science Laboratory has been delayed for two years and will now launch in the fall of 2011. The decision to delay is based on various technical problems the MSL team has encountered and having enough time to work through the problems, as well as provide adequate time for testing all the systems on the car-sized rover. The main problems are the actuators, the gear boxes for all the moving parts. Mars program manager Doug McCuistion said the team is actually only a few months behind schedule, but in going to Mars, that doesn’t matter since a launch window to the Red Planet only comes once every 26 months. “We know these actuator motors must work on Mars and we’ve got anomalies on some of them we don’t understand,” said McCuistion. “It’s the right thing to delay the mission to take the appropriate time to understand the technical issues and test everything thoroughly.”

“Failure is not an option for this mission,” said Ed Weiler, NASA’s associate administrator for science.

The MSL mission will send a next-generation rover with unprecedented research tools to study the early environmental history of Mar, with the fundamental purpose to explore if the conditions for microbial life on Mars ever existed, or if they exist now.

The slip to 2011 will cost $400 million, making the total cost the mission about 2.2-2.3 billion in life cycle costs.

Weiler said there will some “pain” in planetary science and other Mars missions, but there will be paybacks, and no cancelations of any missions or programs are expected. There could be subsequent delays in other missions, however.

“There’s nobody who would like to launch in 2009 more than this team,” said JPL Director Charles Elachi. “These are the same people who put the face of NASA on the front page of newspapers the past few years with our other Mars missions. Unfortunately despite full support by NASA headquarters and the contractors, we just came a little short on time. The plan is to understand these technical issues, look for solution and do a very comprehensive test program. You can’t rely on luck to be successful on Mars.”

The vast majority of the hardware for the rover has been completed, but not everything is working well, particularly the actuators. NASA officials at today’s press conference all said they can’t send MSL to Mars without knowing everything they can about the issues with the actuators.

“The actuators are basically motors in a gear box,” said McCuistion. “All our landers have robotic actuators, and they enable the rover to do what they do: to drive and stop, they run the elbow and wrist join for the robotic arm and drills in sample handling devices. That’s why they are absolutely crucial to these missions. If the actuators can’t move, we essentially have junk on the surface of Mars.”

There are 31 different actuators on MSL, and 60 flight actuators and 45 engineering actuators are being built. Some of the problems have come from the manufacturing side with workmanship, and the most recent issue is drag torque issues within the devices. “The criticality and the number of these actuators is key,” said Elachi. “These actuators are much more massive than for MER mission since the MSL rover is about 8 times bigger, and they are very sophisticated.”

When asked if NASA had considered canceling the MSL mission, Griffin said absolutely not. “Before canceling I’d have to believe the project is going badly in a technical sense, but it’s not. When you’re doing things that have never been done before, you’re likely to encounter unforeseen difficulties. But just having difficulties is no cause to cancel. We had problems with Hubble, and we had problems with COBE, but I don’t think today anyone regrets having Nobel prize winning science from these missions. Unless you’re interested in building cookie cutter copies of previous spacecraft, and nobody is interested in doing that, you’ll encounter problems with hardware that’s never been built before.”

Source: NASA TV

December 3, 2008December 24, 2015 by Nancy Atkinson

Seeing Venus in a New Light

Venus in ultraviolet. Credits: ESA/MPS/DLR/IDA

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New images taken by instruments on board ESA’s Venus Express are providing insight into the turbulent atmosphere of our neighboring planet. When viewed in beyond visible light, the ultraviolet reveals the structure of the clouds and the dynamic conditions in the atmosphere of Venus, where the infrared provides information on the temperature and altitude of the cloud tops. Most intriguing are the puzzling dark and bright zones seen on Venus in ultraviolet.

Scientists have seen equatorial areas on Venus that appear dark in ultraviolet light, and have been mystified by them. The new views with Venus Express show the cause of these different colored areas is the uneven distribution of a mysterious chemical in the atmosphere that absorbs ultraviolet light, creating the bright and dark zones. While the scientists haven’t been able to identify the chemical, they have figured out the process that causes the changes in cloud types across Venus.

Professor Fred Taylor, one of the Venus Express scientists, from Oxford University said, “The features seen on Venus in ultraviolet light have been a puzzle to astronomers for nearly a century. These new images have revealed the structure in the clouds that produces them and shows how they result from complex meteorological behaviour. We can now study in much greater detail and try to understand the origin of features such as the large hurricane-like vortex over the north and south poles. Like many things on Venus, including global warming, this feature has similarities to atmospheric and environmental process on Earth, but the Venus version is much more extreme.”

With data from Venus Express, scientists have learned that the equatorial areas on Venus that appear dark in ultraviolet light are regions of relatively high temperature, where intense convection brings up dark material from below. In contrast, the bright regions at mid-latitudes are areas where the temperature in the atmosphere decreases with depth.

Venus in infrared and ultraviolet. Credits: VMC ultraviolet image: ESA/MPS/DLR/IDA VIRTIS infrared image: ESA/VIRTIS/INAF-IASF/Obs. de Paris-LESIA

Observations in the infrared have been used to map the altitude of the cloud tops. Researchers were surprised to find the clouds in both the dark tropics and the bright mid-latitudes are located at about the same height of about 72 km.

Sources: ESA, Science & Technology Facilities Council

December 3, 2008December 24, 2015 by Nancy Atkinson

Head-sized Meteorite Found From Canadian Fireball

The 13 kg meteorite is roughly the size of a human head. Bruce McCurdy, Edmonton Space & Science Foundation / Royal Astronomical Society of Canada)

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Several more fragments have been found from the 10-ton asteroid that exploded over western Canada on November 20, including a head-sized piece weighing 13-kilograms (28 lbs). Imagine that landing on your house or car (or head!). University of Calgary professor Alan Hildebrand, who is leading the search estimates there could be 2,000 fragments per hectare (about 2.5 acres) in the area near where fragments were initially found. The asteroid is becoming known as the Buzzard Coulee fireball, named after the picturesque, but luckily uninhabited valley where the first pieces were located. Check out the website of Bruce McCurdy of Edmonton Space & Science Foundation and the Royal Astronomical Society of Canada, who has joined in the search for more meteorite images.

More than two dozen pieces of the asteroid have been found by researchers or members of the public. The search is focused on a 24-square-kilometer section of agricultural land along the Battle River where the scientists calculated the debris would be located. Hildebrand was appreciative all the eyewitness reports and help from the public in obtaining as much information as possible about the fireball that lit up the sky. “I was gratified that my first prediction was close,” he said of his estimate of where the fragments could be found. “We couldn’t have done this so quickly without the eyewitnesses and security camera records, and we still need the security camera records to determine the pre-fall orbit of this asteroid.”

Searchers from the University of Calgary have been joined by other members of the Canadian Space Agency-funded Small Bodies Discipline Working Group, as well as members of the public who wanted to join the search and find a chunk of history. A father and son team found the big 13 kg piece, which was given to the rancher that owned the land on which it was found.

Sources: Bruce McCurdy’s website, University of Calgary

December 3, 2008December 24, 2015 by Nancy Atkinson

Astronomers ‘Time Travel’ to 16th Century Supernova

Tycho's Supernova Remnant. Credit: Spitzer, Chandra and Calar Alto Telescopes.

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On November 11, 1572 Danish astronomer Tycho Brahe and other skywatchers observed what they thought was a new star. A bright object appeared in the constellation Cassiopeia, outshining even Venus, and it stayed there for several months until it faded from view. What Brahe actually saw was a supernova, a rare event where the violent death of a star sends out an extremely bright outburst of light and energy. The remains of this event can still be seen today as Tycho’s supernova remnant. Recently, a group of astronomers used the Subaru Telescope to attempt a type of time travel by observing the same light that Brahe saw back in the 16th century. They looked at ‘light echoes’ from the event in an effort to learn more about the ancient supernova.

A ‘light echo’ is light from the original supernova event that bounces off dust particles in surrounding interstellar clouds and reaches Earth many years after the direct light passes by; in this case, 436 years ago. This same team used similar methods to uncover the origin of supernova remnant Cassiopeia A in 2007. Lead project astronomer at Subaru, Dr. Tomonori Usuda, said “using light echoes in supernova remnants is time-traveling in a way, in that it allows us to go back hundreds of years to observe the first light from a supernova event. We got to relive a significant historical moment and see it as famed astronomer Tycho Brahe did hundreds of years ago. More importantly, we get to see how a supernova in our own galaxy behaves from its origin.”

The view of the light echoes from Tycho’s supernova. Credit: Subaru Telescope

On September 24, 2008, using the Faint Object Camera and Spectrograph (FOCAS) instrument at Subaru, astronomers looked at the signatures of the light echoes to see the spectra that were present when Supernova 1572 exploded. They were able to obtain information about the nature of the original blast, and determine its origin and exact type, and relate that information to what we see from its remnant today. They also studied the explosion mechanism.

What they discovered is that Supernova 1572 was very typical of a Type Ia supernova. In comparing this supernova with other Type Ia supernovae outside our galaxy, they were able to show that Tycho’s supernova belongs to the majority class of Normal Type Ia, and, therefore, is now the first confirmed and precisely classified supernova in our galaxy.

This finding is significant because Type Ia supernovae are the primary source of heavy elements in the Universe, and play an important role as cosmological distance indicators, serving as ‘standard candles’ because the level of the luminosity is always the same for this type of supernova.

For Type Ia supernovae, a white dwarf star in a close binary system is the typical source, and as the gas of the companion star accumulates onto the white dwarf, the white dwarf is progressively compressed, and eventually sets off a runaway nuclear reaction inside that eventually leads to a cataclysmic supernova outburst. However, as Type Ia supernovae with luminosity brighter/fainter than standard ones have been reported recently, the understanding of the supernova outburst mechanism has come under debate. In order to explain the diversity of the Type Ia supernovae, the Subaru team studied the outburst mechanisms in detail.

This observational study at Subaru established how light echoes can be used in a spectroscopic manner to study supernovae outburst that occurred hundreds of years ago. The light echoes, when observed at different position angles from the source, enabled the team to look at the supernova in a three dimensional view. This study indicated Tycho’s supernova was an aspherical/nonsymmetrical explostion. For the future, this 3D aspect will accelerate the study of the outburst mechanism of supernova based on their spatial structure, which, to date, has been impossible with distant supernovae in galaxies outside the Milky Way.

The results of this study appear in the 4 December 2008 issue of the science journal Nature.

Source: Subaru Telescope

December 3, 2008December 24, 2015 by Nancy Atkinson

Brown Dwarfs Form Like Stars

This artist's conception shows the brown dwarf ISO-Oph 102.Credit: ASIAA

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Brown dwarfs are an interesting sort, and can only be classified in a kind of cosmic periphery between stars and planets: they are too small to be called stars and too large to be called planets. And astronomers haven’t been sure whether they form like stars, from the gravitational collapse of gas clouds, or if they form like planets, where rocky material comes together until it grows massive enough to draw in nearby gas. But now strong evidence has been found that brown dwarfs form more like stars. Using the Smithsonian’s Submillimeter Array (SMA), astronomers detected molecules of carbon monoxide shooting outward from a brown dwarf ISO-Oph 102. This type of molecular outflows typically is seen coming from young stars or protostars. However, this object has an estimated mass of 60 Jupiters, meaning it is too small to be a star, and has therefore been classified as a brown dwarf. But this new finding means brown dwarfs are more like stars than planets.

Typically, brown dwarfs have masses between 15 and 75 Jupiters, and the theoretical minimum mass for a star to sustain nuclear fusion is 75 times Jupiter. As a result, brown dwarfs are sometimes called failed stars. A star forms when a cloud of interstellar gas draws itself together through gravity, growing denser and hotter until fusion ignites. If the initial gas cloud is rotating, that rotation will speed up as it collapses inward, much like an ice skater drawing her arms in. In order to gather mass, the young protostar must somehow shed that angular momentum. It does so by spewing material in opposite directions as a bipolar outflow.

ISO-Oph 102 offers the first strong evidence in favor of brown dwarf formation through gravitational collapse. Credit: David A. Aguilar (CfA)

A brown dwarf is less massive than a star, so there is less gravity available to pull it together. As a result, astronomers debated whether a brown dwarf could form the same way as a star. Previous observations provided hints that they could. The serendipitous discovery of a bipolar molecular outflow at ISO-Oph 102 offers the first strong evidence in favor of brown dwarf formation through gravitational collapse.

As might be expected, the outflow contains much less mass than the outflow from a typical star: about 1000 times less, in fact. The outflow rate is also smaller by a factor of 100. In all respects, the molecular outflow of ISO-Oph 102 is a scaled-down version of the outflow process seen in young stars.

“These findings suggest that brown dwarfs and stars aren’t different because they formed in different ways,” said Paul Ho, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of ASIAA. “They share the same formation mechanism. Whether an object ends up as a brown dwarf or star apparently depends only on the amount of available material.”

The paper on ISO-Oph 102 will be published in the December 20 issue of the Astrophysical Journal Letters.

Source: CfA

December 3, 2008December 24, 2015 by Nancy Atkinson

This Week’s Where In The Universe Challenge

Are you ready for another Where In The Universe Challenge? Take a look at the image above and see if you can name where in the Universe this image is from. Give yourself extra points if you can name the spacecraft responsible for the image. We’ll provide the image today, but won’t reveal the answer until tomorrow. This gives you a chance to mull over the image and provide your answer/guess in the comment section — if you dare! Check back tomorrow on this same post to see how you did. Good luck!

UPDATE (12/4): The answer has now been posted below. If you haven’t made your guess yet, no peeking before you do!!

A variety of guesses this week, but many answers were correct: Saturn’s moon Iapetus. The Cassini spacraft zoomed in on the cratered moon to provide this stunning close-up. And did you know you can golf the moons of Saturn? The Cassini scientists created a Flash-based game based on some of the best images from the spacecraft’s tour of Saturn and its moons. It’s called Golf Sector 6, and its pretty fun. As many of you mentioned, this image shows the equatorial bulge of Iapetus, with mountainous terrain reaching about 10 km in height. Above the middle of the image can be seen a place where an impact has exposed the bright ice beneath the dark overlying material.

The image was taken on 10 September 2007 with the Cassini’s narrow-angle camera at a distance of approximately 3870 km from Iapetus. Image scale is 23 m per pixel. Credits: NASA/ JPL/ Space Science Institute.

And you know-it-alls out there don’t have to provide links to images or videos in your guesses! Give everyone the equal chance to play, please!

Tune in again next week for another WITU challenge!