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Venus Peeps Back Into View at Dusk

After a long drought, a bright planet emerges in the western sky. Welcome back, Venus!

The post Venus Peeps Back Into View at Dusk appeared first on Sky & Telescope.

NASA Vs. SpaceX: Só Desenhando...Presta Atençao Mamae!!! - Space Today TV Ep.1117

napkitores.hu - 8 óra 57 perc
Um vídeo para tentar explicar de forma definitiva, o papel da NASA, da SpaceX de outras empresas e outras agencias no chamado Space Business. O Delta IV Heavy nao é da NASA!!! E nao...

Russia and China Are Working on Space and Counterspace Weapons

universetoday - 17 óra 33 perc

Every year, the Department of National Intelligence (DNI) releases its Worldwide Threat Assessment of the US Intelligence Community. This annual report contains the intelligence community’s assessment of potential threats to US national security and makes recommendations accordingly. In recent years, these threats have included the development and proliferation of weapons, regional wars, economic trends, terrorism, cyberterrorism, etc.

This year’s assessment, which was released on February 8th, 2018, was certainly a mixed bag of warnings. Among the many potential threats to national security, the authors emphasized the many recent developments taking place in space. According to their assessment, the expansion of the global space industry, growing cooperation between the private and public sector, and the growth of various states in space, could constitute a threat to US national security.

Naturally, the two chief actors that are singled out were China and Russia. As they indicate, these countries will be leading the pack in the coming years when it comes to expanding space-based reconnaissance, communications and navigation systems. This will not only enable their abilities (and those of their allies) when it comes to space-based research, but will have military applications as well.

The second flight of the Long March 5 lifting off from Wenchang on July 2nd, 2017. Credit: CNS

As they state in the section of the report titled “Space and Counhttps://www.dni.gov/files/documents/Newsroom/Testimonies/2018-ATA—Unclassified-SSCI.pdfterspace“:

“Continued global space industry expansion will further extend space-enabled capabilities and space situational awareness to nation-state, nonstate, and commercial space actors in the coming years, enabled by the increased availability of technology, private-sector investment, and growing international partnerships for shared production and operation… All actors will increasingly have access to space-derived information services, such as imagery, weather, communications, and positioning, navigation, and timing for intelligence, military, scientific, or business purposes.”

A key aspect of this development is outlined in the section titled “Emerging and Disruptive Technology,” which addresses everything from the development of AI and internet technologies to additive manufacturing and advanced materials. In short, it not just the development of new rockets and spacecraft that are at issue here, but the benefits brought about by cheaper and lighter materials, more rapid information sharing and production.

“Emerging technology and new applications of existing technology will also allow our adversaries to more readily develop weapon systems that can strike farther, faster, and harder and challenge the United States in all warfare domains, including space,” they write.

Artist’s illustration of China’s 8-ton Tiangong-1 space station, which is expected to fall to Earth in late 2017. Credit: CMSE

Specifically, anti-satellite (ASAT) weapons are addressed as the major threat. Such technologies, according to the report, have the potential to reduce US and allied military effectiveness by disrupting global communications, navigation and coordination between nations and armies. These technologies could be destructive, in the form of anti-satellite missiles, but also nondestructive – i.e. electromagnetic pulse (EMP) devices. As they indicate:

“We assess that, if a future conflict were to occur involving Russia or China, either country would justify attacks against US and allied satellites as necessary to offset any perceived US military advantage derived from military, civil, or commercial space systems. Military reforms in both countries in the past few years indicate an increased focus on establishing operational forces designed to integrate attacks against space systems and services with military operations in other domains.”

The authors further anticipate that Russian and Chinese destructive ASAT technology could reach operational capacity within a few years time. To this end, they cite recent changes in the People’s Liberation Army (PLA), which include the formation of military units that have training in counter-space operations and the development of ground-launched ASAT missiles.

While they are not certain about Russia’s capability to wage ASAT warfare, they venture that similar developments are taking place. Another area of focus is the development of directed-energy weapons for the purpose of blinding or damaging space-based optical sensors. This technology is similar to what the US investigated decades ago for the sake of strategic missile defense – aka. the Strategic Defense Initiative (SDI).

An artist’s concept of a Space Laser Satellite Defense System. Credit: USAF

While these weapons would not be used to blow up satellites in the conventional sense, they would be capable of blinding or damaging sensitive space-based optical sensors. On top of that, the report cites how Russia and China continue to conduct on-orbit activities and launching satellites that are deemed “experimental”. A good example of this was a recent proposal made by researchers from the Information and Navigation College at China’s Air Force Engineering University.

The study which detailed their findings called for the deployment of a high-powered pulsed ablative laser that could be used to break up space junk. While the authors admit that such technology can have peaceful applications – ranging from satellite inspection, refueling and repair – they could also be used against other spacecraft. While the United States has been researching the technology for decades, China and Russia’s growing presence in space threatens to tilt this balance of power.

Moreover, there are the loopholes in the existing legal framework – as outlined in the Outer Space Treaty – which the authors believe China and Russia are intent on exploiting:

“Russia and China continue to publicly and diplomatically promote international agreements on the nonweaponization of space and “no first placement” of weapons in space. However, many classes of weapons would not be addressed by such proposals, allowing them to continue their pursuit of space warfare capabilities while publicly maintaining that space must be a peaceful domain.”

Artist’s impression of a laser removing orbital debris, based on NASA pictures. Credit: Fulvio314/NASA/Wikipedia Commons

For example, the Outer Space Treaty bars signatories from placing weapons of mass destruction in orbit of Earth, on the Moon, on any other celestial body, or in outer space in general. By definition, this referred to nuclear devices, but does not extend to conventional weapons in orbit. This leaves room for antisatellite platforms or other conventional space-based weapons that could constitute a major threat.

Beyond China and Russia, the report also indicates that Iran’s growing capabilities in rocketry and missile technology could pose a threat down the road. As with the American and Russian space programs, developments in space rocketry and ICBMs are seen as being complimentary to each other:

“Iran’s ballistic missile programs give it the potential to hold targets at risk across the region, and Tehran already has the largest inventory of ballistic missiles in the Middle East. Tehran’s desire to deter the United States might drive it to field an ICBM. Progress on Iran’s space program, such as the launch of the Simorgh SLV in July 2017, could shorten a pathway to an ICBM because space launch vehicles use similar technologies.”

All told, the report makes some rather predictable assessments. Given China and Russia’s growing power in space, it is only natural that the DNI would see this as a potential threat. However, that does not mean that one should assume an alarmist attitude. When it comes to assessing threats, points are awarded for considering every contingency. But if history has taught us anything, it’s that assessment and realization are two very different things.

Remember Sputnik? The lesson there was clear. Don’t panic!

Further Reading: DNI

The post Russia and China Are Working on Space and Counterspace Weapons appeared first on Universe Today.

NASA Budget Proposal Would Cancel WFIRST

skyandtelescope.com-MostRecent - 2018. február 20. 22:49

The recent budget proposal for NASA dealt a blow to the astronomical community, putting several key missions — including WFIRST, a successor to Hubble — under the financial axe.

The post NASA Budget Proposal Would Cancel WFIRST appeared first on Sky & Telescope.

Astronomers Observe the Rotating Accretion Disk Around the Supermassive Black Hole in M77

universetoday - 2018. február 20. 19:12

During the 1970s, scientists confirmed that radio emissions coming from the center of our galaxy were due to the presence of a Supermassive Black Hole (SMBH). Located about 26,000 light-years from Earth between the Sagittarius and Scorpius constellation, this feature came to be known as Sagittarius A*. Since that time, astronomers have come to understand that most massive galaxies have an SMBH at their center.

What’s more, astronomers have come to learn that black holes in these galaxies are surrounded by massive rotating toruses of dust and gas, which is what accounts for the energy they put out. However, it was only recently that a team of astronomers, using the the Atacama Large Millimeter/submillimeter Array (ALMA), were able to capture an image of the rotating dusty gas torus around the supermassive black hole of M77.

The study which details their findings recently appeared in the Astronomical Journal Letters under the title “ALMA Reveals an Inhomogeneous Compact Rotating Dense Molecular Torus at the NGC 1068 Nucleus“. The study was conducted by a team of Japanese researchers from the National Astronomical Observatory of Japan – led by Masatoshi Imanishi – with assistance from Kagoshima University.

The central region of the spiral galaxy M77. The NASA/ESA Hubble Space Telescope imaged the distribution of stars. ALMA revealed the distribution of gas in the very center of the galaxy. Credit: ALMA (ESO/NAOJ/NRAO)/Imanishi et al./NASA/ESA Hubble Space Telescope and A. van der Hoeven

Like most massive galaxies, M77 has an Active Galactic Nucleus (AGN), where dust and gas are being accreted onto its SMBH, leading to higher than normal luminosity. For some time, astronomers have puzzled over the curious relationship that exists between SMBHs and galaxies. Whereas more massive galaxies have larger SMBHs, host galaxies are still 10 billion times larger than their central black hole.

This naturally raises questions about how two objects of vastly different scales could directly affect each other. As a result, astronomers have sought to study AGN is order to determine how galaxies and black holes co-evolve. For the sake of their study, the team conducted high-resolution observations of the central region of M77, a barred spiral galaxy located about 47 million light years from Earth.

Using ALMA, the team imaged the area around M77’s center and were able to resolve a compact gaseous structure with a radius of 20 light-years. As expected, the team found that the compact structure was rotating around the galaxies central black hole. As Masatoshi Imanishi explained in an ALMA press release:

“To interpret various observational features of AGNs, astronomers have assumed rotating donut-like structures of dusty gas around active supermassive black holes. This is called the ‘unified model’ of AGN. However, the dusty gaseous donut is very tiny in appearance. With the high resolution of ALMA, now we can directly see the structure.”

Motion of gas around the supermassive black hole in the center of M77. The gas moving toward us is shown in blue and that moving away from us is in red. Credit: ALMA (ESO/NAOJ/NRAO), Imanishi et al.

In the past, astronomers have observed the center of M77, but no one has been able to resolve the rotating torus at its center until now. This was made possible thanks to the superior resolution of ALMA, as well as the selection of molecular emissions lines. These emissions lines include hydrogen cyanide (HCN) and formyl ions (HCO+), which emit microwaves only in dense gas, and carbon monoxide – which emits microwaves under a variety of conditions.

The observations of these emission lines confirmed another prediction made by the team, which was that the torus would be very dense. “Previous observations have revealed the east-west elongation of the dusty gaseous torus,” said Imanishi. “The dynamics revealed from our ALMA data agrees exactly with the expected rotational orientation of the torus.”

However, their observations also indicated that the distribution of gas around an SMBH is more complicated that what a simple unified model suggests. According to this model, the rotation of the torus would follow the gravity of the black hole; but what Imanishi and his team found indicated that gas and dust in the torus also exhibit signs of highly random motion.

These could be an indication that the AGN at the center of M77 had a violent history, which could include merging with a small galaxy in the past. In short, the team’s observations indicate that galactic mergers may have a significant impact on how AGNs form and behave. In this respect, their observations of M77s torus are already providing clues as to the galaxy’s history and evolution.

NASA’s Spitzer Space Telescope captured this stunning infrared image of the center of the Milky Way Galaxy, where the black hole Sagitarrius A resides. Credit: NASA/JPL-Caltech

The study of SMBHs, while intensive, is also very challenging. On the one hand, the closest SMBH (Sagitarrius A*) is relatively quiet, with only a small amount of gas accreting onto it. At the same time, it is located at the center of our galaxy, where it is obscured by intervening dust, gas and stars. As such, astronomers are forced to look to other galaxies to study how SMBHs and their galaxies co-exist.

And thanks to decades of study and improvements in instrumentation, scientists are beginning to get a clear glimpse of these mysterious regions for the first time. By being able to study them in detail, astronomers are also gaining valuable insight into how such massive black holes and their ringed structures could coexist with their galaxies over time.

Further Reading: ALMA, arXiv

The post Astronomers Observe the Rotating Accretion Disk Around the Supermassive Black Hole in M77 appeared first on Universe Today.

NASA's James Webb Space Telescope to reveal secrets of the Red Planet

sciencedaily.com - 2018. február 20. 18:47
Mars rovers and orbiters have found signs that Mars once hosted liquid water on its surface. Much of that water escaped over time. How much water was lost, and how does the water that’s left move from ice to atmosphere to soil? During its first year of operations, NASA’s James Webb Space Telescope will seek answers. Webb also will study mysterious methane plumes that hint at possible geological or even biological activity.

Laser-ranged satellite measurement now accurately reflects Earth's tidal perturbations

sciencedaily.com - 2018. február 20. 18:30
Tides on Earth have a far-reaching influence, including disturbing satellites' measurements by affecting their motion. The LAser RElativity Satellite (LARES), is the best ever relevant test particle to move in the Earth's gravitational field. In a new study, LARES proves its efficiency for high-precision probing of General Relativity and fundamental physics.

No relation between a supermassive black hole and its host galaxy!?

sciencedaily.com - 2018. február 20. 18:30
Using ALMA to observe an active galaxy with a strong ionized gas outflow from the galactic center, a team has obtained a result making astronomers even more puzzled -- the team clearly detected CO gas associated with the galactic disk, yet they have also found that the CO gas which settles in the galaxy is not affected by the strong ionized gas outflow launched from the galactic center.

Astronomers reveal secrets of most distant supernova ever detected

sciencedaily.com - 2018. február 20. 16:24
Astronomers have confirmed the discovery of the most distant supernova ever detected -- a huge cosmic explosion that took place 10.5 billion years ago, or three-quarters the age of the Universe itself.

'Ultramassive' black holes discovered in far-off galaxies

sciencedaily.com - 2018. február 20. 15:32
Thanks to data collected by NASA’s Chandra X-ray telescope on galaxies up to 3.5 billion light years away from Earth, an international team of astrophysicists was able to detect what is likely to be the most massive black holes ever discovered in the universe. The team’s calculations showed that these “ultramassive” black holes are growing faster than the stars in their respective galaxies.

Subway Surfers World Tour 2018 - Paris - Sun Beijing Special VS Sun Spot Outfit

napkitores.hu - 2018. február 20. 08:45
Subway Surfers World Tour 2018 - Paris - Sun Beijing Special VS Sun Spot Outfit.

Foguete Brasileiro vs SpaceX

napkitores.hu - 2018. február 20. 08:45
A iniciativa privada dá conta de investir em inovaçoes tecnológicas? Ou devemos sempre financiar tais pesquisas por meio de financiamento compulsório dos pagadores de impostos tendo o...

Opportunity Just Saw its 5,000th Sunrise on Mars

universetoday - 2018. február 20. 03:19

It’s been a time of milestones for Mars rovers lately! Last month (on January 26th, 2018), NASA announced that the Curiosity rover had spent a total of 2,000 days on Mars, which works out to 5 years, 5 months and 21 days. This was especially impressive considering that the rover was only intended to function on the Martian surface for 687 days (a little under two years).

But when it comes to longevity, nothing has the Opportunity rover beat! Unlike Curiosity, which relied on a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) for power, the solar-powered Opportunity recently witnessed its five-thousandth sunrise on Mars. This means that the rover has remained in continuous operation for 5000 sols, which works out to 5137.46 Earth days.

This five-thousandth sunrise began on Friday, Feb. 16th, 2018 – roughly 14 Earth years (and 7.48 Martian years) after the rover first landed. From its position on the western rim of the Endeavour Crater, the sunrise appeared over the basin’s eastern rim, about 22 km (14 mi) away. This location, one-third of the way down “Perseverance Valley”, is more than 45 km (28 mi) from Opportunity’s original landing site.

Mosaic view looking down from inside the upper end of “Perseverance Valley” on the inner slope of Endeavour Crater’s western rim. Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Ken Kremer/kenkremer.com

This is especially impressive when you consider that the original science mission was only meant to last 90 sols (92.47 Earth days) and NASA did not expect the rover to survive its first Martian winter. And yet, the rover has not only survived all this time, it continues to send back scientific discoveries from the Red Planet. As John Callas, the Opportunity Project Manager at NASA’s Jet Propulsion Laboratory, explained in a NASA press release:

“Five thousand sols after the start of our 90-sol mission, this amazing rover is still showing us surprises on Mars… We’ve reached lots of milestones, and this is one more, but more important than the numbers are the exploration and the scientific discoveries.”

For instance, the rover has provided us with 225,000 images since its arrival, and revealed that ancient Mars was once home to extensive groundwater and surface water. Beginning in 2008, it began working its way across the  Endeavour Crater in order to get a glimpse deeper into Mars’ past. By 2011, it had reached the crater’s edge and confirmed that mineral-rich water once flowed through the area.

At present, researchers are using Opportunity to investigate the processes that shaped Perseverance Valley, an area that descends down the slope of the western rim of Endeavour Crater. Here too, Opportunity has learned some fascinating things about the Red Planet. For instance, the rover has conducted observations of possible “rock stripes” in the valley, which could be indicative of its valley’s origin.

Textured rows on the ground in this portion of “Perseverance Valley” are under investigation by NASA’s Mars Exploration Rover Opportunity. Credits: NASA/JPL-Caltech

These stripes are of interest to scientists because of the way they resemble rock stripes that appear on mountain slopes here on Earth, which are the result of repeated cycles of freezing and thawing on wet soil. On Mauna Kea, for example, soil freezes every night, but is often dry due to the extreme elevation. This causes soils that have high concentrations of silt, sand and gravel to expand, pushing the larger particles up.

These particles then form stripes as they fall downhill, or are moved by wind or rainwater, and cause the ground to expand less in this space. This process repeats itself over and over, creating a pattern that leads to distinct stripes. As Opportunity observed, there are slopes within the Perseverance Valley where soil and gravel particles appear to have formed into rows that run parallel to the slope, alternating between rows that have more and less gravel.

In the case of the Perseverance Valley’s stripes, scientists are not sure how they formed, but think they could be the result of water, wind, downhill transport, other processes, or a combination thereof. Another theory posits that features like these could be the result of changes in Mars tilt (obliquity) which happen over the course of hundreds of thousands of years.

During these periods, Mars’ axial tilt increases to the point where water frozen at the poles will vaporize and become deposited as snow or frost nearer to the equator. As Ray Arvidson, the Opportunity Deputy Principal Investigator at Washington University, explahttps://www.nasa.gov/feature/jpl/long-lived-mars-rover-opportunity-keeps-finding-surprisesined:

“One possible explanation of these stripes is that they are relics from a time of greater obliquity when snow packs on the rim seasonally melted enough to moisten the soil, and then freeze-thaw cycles organized the small rocks into stripes. Gravitational downhill movement may be diffusing them so they don’t look as crisp as when they were fresh.”

Stone stripes on the side of a volcanic cone on Mauna Kea, Hawaii, which are made of small rock fragments that are aligned downhill. These are formed when freeze-thaw cycles lift them out of the finer-grained regolith and move them to the sides, forming stone stripes. Credits: Washington University in St. Louis/NASA

Having the chance to investigate these features is therefore quite the treat for the Opportunity science team. “Perseverance Valley is a special place, like having a new mission again after all these years.” said Arvidson. “We already knew it was unlike any place any Mars rover has seen before, even if we don’t yet know how it formed, and now we’re seeing surfaces that look like stone stripes. It’s mysterious. It’s exciting. I think the set of observations we’ll get will enable us to understand it.”

Given the state of the Martian surface, it is a safe bet that wind is largely responsible for the rock stripes observed in Perseverance Valley. In this respect, they would be caused by sand blown uphill from the crater floor that sorts larger particles into rows parallel to the slope. As Robert Sullivan, an Opportunity science-team member of Cornell University, explained:

“Debris from relatively fresh impact craters is scattered over the surface of the area, complicating assessment of effects of wind. I don’t know what these stripes are, and I don’t think anyone else knows for sure what they are, so we’re entertaining multiple hypotheses and gathering more data to figure it out.”

Despite being in service for a little over 14 years, and suffering its share of setbacks, Opportunity is once again in a position to reveal things about Mars’ past and how it evolved to become what it is today. Never let it be said that an old rover can’t reveal new secrets! If there’s one thing Opportunity has proven during its long history of service on Mars, it is that the underdog can make some of the greatest contributions.

Further Reading: NASA, NASA (2)

The post Opportunity Just Saw its 5,000th Sunrise on Mars appeared first on Universe Today.

Subscribe to Our New Weekly Email Newsletter Written By Fraser

universetoday - 2018. február 20. 01:28

It’s been almost 19 years since I founded Universe Today, back in March, 1999.

Back when I started, it was a primarily an email-based newsletter with an archive version on the web where people could read it if they wanted to.

The technology was pretty rudimentary at the time, so I had to do everything by hand, sending out a BCC email to thousands of people every day, eventually finding other email mailing list providers. At some point, I shifted from commentary and summaries to full on reporting on space news. And at that time, automated tools arrived that would take all the stories you wrote in a day, bundled them up and sent them out via email to a list of subscribers.

That was great and convenient for me, but it didn’t make for the best experience. It lost its soul.

A couple of months ago, I decided to return to my roots and continue maintaining a weekly email newsletter that summarizes some of the top stories that happened this week. And not just stories from here on Universe Today, but stories from across the Universe of space journalists and websites, including Space.com, Ars Technica, Ethan Siegel, Brian Koberlein, TheVerge and many more. I see more amazing things out there than we could ever report on. I figured I might as well share it.

Each edition of the weekly newsletter comes out on Friday, and is hand-written personally by me, and includes a few dozen summaries and links to stories on Universe Today and beyond, as well as cool pictures, videos, and astrophotography.

Here’s an example of what it looks like.

It’s SPAM free, I won’t sell the email addresses to anyone. There aren’t any ads in them, although I’ll occasionally promote books, trips and other projects I’m working on, but tastefully, I promise.

And you can unsubscribe any time you like.

If that sounds good to you, go here and sign up.

The post Subscribe to Our New Weekly Email Newsletter Written By Fraser appeared first on Universe Today.

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