- Astronomers Find New Details in First Known Spiral Galaxy
- Infrared View of the Trifid Nebula Reveals New Variable Stars Far Beyond
- Sierra Nevada Completes Dream Chaser Study with German Aerospace Industry Partners
- Second Edition of the Photo Nightscape Awards Launches
- White House Proposes $18.5 Billion Budget for NASA
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Posted: 04 Feb 2015 04:29 AM PST
Case Western Reserve University astronomers peered deep into space to discover new features of a galaxy that's been sketched and photographed for 170 years. The researchers were able to see faint plumes extending from the northeast and south of the nearby spiral galaxy M51a, also called the "Whirlpool Galaxy," by taking what is essentially a photograph made by a 20-hour exposure. The image also provides new details of the linear northwest plume, which itself is nearly 120,000 light-years long, and reveals a lack of stars in a portion of the southeast tail. "These features can be used in future modeling to understand the history of M51, when it and its companion galaxy first started to interact," said Aaron Watkins, a PhD student in the department of astronomy at Case Western Reserve and lead author of the study.
Modeling that's already been done fails to match the structures of the system, ages and more. Watkins worked with the CWRU astronomy professor Chris Mihos and Observatory Manager Paul Harding. The research is published in Astrophysical Journal Letters at: http://iopscience.iop.org/ M51a is the first known spiral galaxy, identified and sketched by William Parsons, the Earl of Rosse, in 1845. The whirlpool and its small companion, M51b, are in the hunting dogs constellation, Canes Venatici, about 31 million light years away. "No professional astronomer we know of has ever taken such a deep image of this galaxy," Watkins said. The images were taken from the CWRU's Burrell Schmidt telescope at Kitt Peak National Observatory near Tucson during February, March and April in 2010 and 2012. The team aimed the telescope at M51 on moonless nights and exposed its digital camera to the light from the galaxy at 20-minute intervals, recalibrating in between. For a total of 10 hours, light was filtered to reveal younger stars. For anther 10 hours, light was filtered to reveal older stars. These 10-hour images were merged to create the 20-hour final image. The northwest plume was seen in the 1970s, but the technology provided limited detail. The astronomers found it's dominated by older, redder stars and has little gas, found in small patches. Due to the age of the stars and the extreme length of the plume, they suggest the plume was created by the interaction of an outer disk of M51 with another galaxy 200 million years ago or more. The southern plume is an oddity. It has no morphological similarities with the surrounding parts of M51 and no gas. The plume has comparatively few stars and, therefore, mass, and little total light. One possibility, the researchers suggest, is the plume could be the remnants of a third satellite or body in the M51 system. The northeast plume has about the same total light as the southern one. It may be an extension of the north side of the galaxy, but that is impossible to tell, Watkins said. Other researchers discovered the southeastern gas tail in 1990 and assumed it was pulled out during an interaction with another galaxy. This new, deeper view still found no stars. That's unusual for such a tail, but it provides a clear test for future interaction models. The astronomers are now devising other ways to look at M51, particularly to gather more detail from the faint plumes. The northwest plume is bright enough that it may be a good candidate for further study using the Hubble telescope, Watkins said. Credit: eurekalert.org  | ||||
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Posted: 04 Feb 2015 03:00 AM PST
A new image taken with European Southern Observatory's (ESO) VISTA survey telescope reveals the famous Trifid Nebula in a new and ghostly light. By observing in infrared light, astronomers can see right through the dust-filled central parts of the Milky Way and spot many previously hidden objects. In just this tiny part of one of the VISTA surveys, astronomers have discovered two unknown and very distant Cepheid variable stars that lie almost directly behind the Trifid. They are the first such stars found that lie in the central plane of the Milky Way beyond its central bulge. As one of its major surveys of the southern sky, the VISTA telescope at ESO’s Paranal Observatory in Chile is mapping the central regions of the Milky Way in infrared light to search for new and hidden objects. This VVV survey (standing for VISTA Variables in the Via Lactea) is also returning to the same parts of the sky again and again to spot objects that vary in brightness as time passes.
A tiny fraction of this huge VVV dataset has been used to create this striking new picture of a famous object, the star formation region Messier 20, usually called the Trifid Nebula, because of the ghostly dark lanes that divide it into three parts when seen through a telescope.
The familiar pictures of the Trifid show it in visible light, where it glows brightly in both the pink emission from ionised hydrogen and the blue haze of scattered light from hot young stars. Huge clouds of light-absorbing dust are also prominent. But the view in the VISTA infrared picture is very different. The nebula is just a ghost of its usual visible-light self. The dust clouds are far less prominent and the bright glow from the hydrogen clouds is barely visible at all. The three-part structure is almost invisible.
In the new image, as if to compensate for the fading of the nebula, a spectacular new panorama comes into view. The thick dust clouds in the disc of our galaxy that absorb visible light allow through most of the infrared light that VISTA can see. Rather than the view being blocked, VISTA can see far beyond the Trifid and detect objects on the other side of the galaxy that have never been seen before.
By chance this picture shows a perfect example of the surprises that can be revealed when imaging in the infrared. Apparently close to the Trifid in the sky, but in reality about seven times more distant, a newly discovered pair of variable stars has been found in the VISTA data. These are Cepheid variables, a type of bright star that is unstable and slowly brightens and then fades with time. This pair of stars, which the astronomers think are the brightest members of a cluster of stars, are the only Cepheid variables detected so far that are close to the central plane, but on the far side of the galaxy. They brighten and fade over a period of eleven days.
The Trifid Nebula lies about 5200 light-years from Earth, the centre of the Milky Way is about 27,000 light-years away, in almost the same direction, and the newly discovered Cepheids are at a distance of about 37 000 light-years.
These results were presented in a paper entitled “Discovery of a Pair of Classical Cepheids in an Invisible Cluster Beyond the Galactic Bulge”, by I. Dekany et al., recently published in Astrophysical Journal Letters.
Credit: ESO
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Posted: 03 Feb 2015 11:28 PM PST
Sierra Nevada Corporation’s (SNC) Space Systems and OHB System AG (OHB) announce the completion of the initial Dream Chaser for European Utilization (DC4EU) study co-funded by the Space Administration of the German Aerospace Center (DLR) and OHB. OHB and DLR are both based in Germany. As announced by the companies in late 2013, SNC and OHB entered into an agreement to study the feasibility of using SNC’s Dream Chaser spacecraft for a variety of missions. The DC4EU study thoroughly reviewed applications for the Dream Chaser including crewed and uncrewed flights to low-Earth orbit (LEO) for missions such as microgravity science, satellite servicing and active debris removal (ADR).
“The inherent design advantages of the Dream Chaser reusable lifting body spacecraft make it an ideal vehicle for a broad range of space applications,” said Dr. Fritz Merkle, member of the Executive Management Board of OHB AG. “We partnered with SNC to study how the design of the Dream Chaser can be used to advance European interests in space. The study results confirm the viability of using the spacecraft for microgravity science and ADR. DC4EU can benefit the entire international space community with its unique capabilities. We look forward to further maturing our design with SNC as we expand our partnership.”
In addition to the study, OHB supported SNC as an exhibitor at the American Society for Gravitational Space Research Conference in late October. During the conference, SNC presented the Dream Chaser spacecraft microgravity research capability for the first time including the debut of a full scale mock-up of the Dream Chaser for Science mission variant.
The DC4EU study is SNC’s first contracted international effort to explore the broad capabilities of the Dream Chaser vehicle.
“We highly value our partnership with the German Aerospace Center and industry teammates, we see this study as the first step towards achieving broad scientific and servicing applications for international missions,” said Dr. John Olson, vice president of Space Exploration Systems for SNC’s Space Systems. “SNC is currently working with OHB on the next phase of our ongoing DC4EU collaboration together with DLR and will be announcing further details in the near future.
SNC’s Dream Chaser is a multi-mission-capable space utility vehicle that is able to flexibly operate as an independent science platform, logistics enabler, or orbital servicing vehicle with the ability to deploy, retrieve, repair, replace, refuel, or assemble items in space. Dream Chaser provides the only reusable, human-rated, lifting-body spacecraft with a commercial runway landing capability, anywhere in the world - offering safe, affordable, flexible and reliable transportation to space.
Credit: sncorp.com
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Posted: 03 Feb 2015 02:33 PM PST
The French Astronomical Association (Association Française d’Astronomie - AFA) on Feb. 1, 2015 launched the second edition of the Photo Nightscape Awards (PNA 2015). Opened to hobbyist and professional photographers from around the world, the PNA rewards the most beautiful pictures of night landscapes in 4 categories (‘Nightscape’, ‘In Town’, ‘Timelapses’ and ‘Junior’). The winning photographers will be awarded a trip to Chile to visit the Very Large Telescope, a trip to the Alqueva Dark Sky Reserve in Portugal, cameras, telescopes and binoculars.
New trend of astrophotography, the Nightscape or night scenery, requires photographers to inculde a landscape and a night skyscape on the same photograph.
The prize is intended to reward the best nightscape shooting (photo or timelapse) in different categories and fulfilling these criteria: shootings (photo or video) must represent a nocturnal landscape, composed of both heavenly and earthly elements—shootings must occur after sunset and before sunrise.
Photographers can send their application forms from Feb. 1 to Sept. 30, 2015.
The award ceremony will take place on Nov. 7, 2015, at the planetarium of the Cité des Sciences et de l'Industrie in Paris. A selection of the best photographs and timelapses will be presented.
The PNA is organized in partnership with the ESO, Nikon, La Cité des Sciences et de l’Industrie de Paris, AIP, the Alqueva Dark Sky Reserve, the Refuge aux Etoiles, Médas and Picto Laboratory.
To enter the contest, visit: www.photonightscapeawards.com
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Posted: 03 Feb 2015 01:45 PM PST
The Obama Administration on Monday proposed a NASA budget allocation of $18.5 Billion for the new Fiscal Year (FY) 2016, which amounts to a half-billion dollar increase over the enacted budget for FY 2015, and keeps the key manned capsule and heavy lift rocket programs on track to launch humans to deep space in the next decade and significantly supplements the commercial crew initiative to send astronauts to low Earth orbit and the space station later this decade. "I am delighted to present President Obama’s FY 2016 budget request for NASA," NASA Administrator Charles Bolden said in a statement. "President Obama’s strong investment in NASA has spurred innovation and economic growth and enabled breakthroughs in science and technology. Space is good for the economy. It’s good for our future and it helps unify the entire world."
Bolden delivered his annual State of NASA speech on Monday in the High Bay of the Neil Armstrong Operations & Checkout Building in Florida. The core message he delivered was that President Obama has proposed a NASA budget for FY 2016, an increase of $500 million over last year’s budget. Bolden said this increase validates the faith that the country has in the Space Agency.
He told the audience: “I want every single American to feel the pride we feel when we talk about what we do at NASA. When you fly on any commercial aircraft, NASA is there with you. NASA developed the lighter composite materials and oxygen sensors that are used in every airplane today. The shock absorbers developed for the Space Shuttle are used today to protect buildings during earthquakes.”
All of the agency's major efforts, including plans for future missions to deep space and Mars, are featured in the details of the new budget.
The commercial crew program would receive $1.24 billion, which NASA officials say is necessary to keep the program on schedule for crew transportation to the International Space Station in 2017. The amount is more than $400 million above current spending.
“Many of the proposals in this budget request continue the good work enacted into law by Congress last year,” stated Commercial Spaceflight Federation President Eric Stallmer. “We applaud the strong support for Commercial Crew and Cargo, Advanced Exploration Systems, and Space Technology’s Flight Opportunities Program, all of which contribute to safe, reliable, and cost-effective capabilities for our nation’s space program. We look forward to working with Congress to fully fund and authorize these innovative commercial approaches to achieve our national space priorities.”
The Administration appears to have once again underfunded the Space Launch System and Orion programs, providing $2.86 billion. The two programs have received more than $3 billion in each of the past two years.
Marshall Space Flight Center's director said Monday that the new 2016 NASA budget proposed by the White House Monday will, if passed by Congress, leave his center "on a solid footing" with "no major program cancellations, no staff reductions or contractor layoffs."
Marshall Director Patrick Scheuermann also said Marshall will deliver the first Space Launch System rocket to Kennedy Space Center in Florida in time for a scheduled launch early in 2018. "The answer is yes," Scheuermann said, "and I'm really proud of the workforce we have."
The White House plan seeks $1.4 billion for planetary science, a drop of roughly 5%. That pot includes funds to capture and study a small asteroid by moving it into the Moon’s orbit. NASA is also requesting $30 million to begin formal planning of a mission to Jupiter’s moon Europa. The mission — to a body whose icy crust covers a watery ocean that could, perhaps, support life — has historically won only lukewarm support from the White House but received much stronger backing from Congress, which set aside $100 million for the plan in 2015.
Science is well funded at $5.29 billion, a slight increase from FY 2015. Space Technology would receive $724.8 million, an increase from the $596 million being spent this year.
The NASA request would boost funding for the Stratospheric Observatory for Infrared Astronomy from $70 million in 2015 to $85 million in 2016. The White House had sought to cut funding for the programme entirely last year, but supporters in Congress kept the specially outfitted Boeing 747 flying.
The agency’s Earth-science programme would get a major boost, increasing by roughly 10% to $1.9 billion. Some of that money would be used to begin planning Landsat-9, the next probe in a series of satellites that has monitored land use and land-cover change since 1972.
Other programs funded in the budget includes its Asteroid Redirect Mission, a variety of space science initiatives and the launch of the James Webb Space Telescope (scheduled for 2018) -- the successor to Hubble.
"The President's request is a move in the right direction," said Space Foundation Chief Executive Officer Elliot Pulham. "The U.S. investment in NASA is a strategic investment in the future - one that fuels our technology base, our global economic competitiveness, and our ability to lead international partnerships," Pulham said.
There are some losers in the new budget as well.
Rather incomprehensibly funding for the long lived Opportunity Mars Exploration Rover is zeroed out in 2016.
This comes despite the fact that the renowned robot just reached the summit of a Martian mountain at Cape Tribulation and is now less than 200 meters from a science goldmine of water altered minerals.
Funding for the Lunar Reconnaissance Orbiter (LRO) is also zeroed out in FY 2016.
Both missions continue to function quite well with very valuable science returns. They were also zeroed out in FY 2015 but received continued funding after a senior level science review.
The agency’s chief financial officer, David Radzanowski, says that NASA will decide in the summer whether to reconsider and continue operating the ageing Opportunity, but there is no guarantee that it will set aside money to do so.
Overall, Bolden was very upbeat about NASA’s future. “I can unequivocally say that the state of NASA is strong,” Bolden said.
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