| | 10 new stories for 2016/03/01
Are Supermassive Black Holes Hiding Matter? 
Mapping the Universe with satellites and ground-based observatories have not only provided scientists with a pretty good understanding of its structure, but also of its composition. And for some time now, they have been working with a model that states that the Universe consists of 4.9% "normal" matter (i.e. that which we can see), 26.8% "dark matter" (that which we can't), and 68.3% "dark energy".From what they have observed, scientists have also concluded that the normal matter in the Universe is concentrated in web-like filaments, which make up about 20% of the Universe by volume. But a recent study performed by the Institute of Astro- and Particle Physics at the University of Innsbruck in Austria has found that a surprising amount of normal matter may live in the voids, and that black holes may have deposited it there. In a paper submitted to the Royal Astronomical Society, Dr. Haider and his team described how they performed measurements of the mass and volume of the Universe's filamentary structures to get a better idea of where the Universe's mass is located. To do this, they used data from the Illustris project - a large computer simulation of the evolution and formation of galaxies.As an ongoing research project run by an international collaboration of scientists (and using supercomputers from around the world), Illustris has created the most detailed simulations of our Universe to date. Beginning with conditions roughly 300,000 years after the Big Bang, these simulations track how gravity and the flow of matter changed the structure of the cosmos up to the present day, roughly 13.8 billion years later.The process begins with the supercomputers simulating a cube of space in the universe, which measures some 350 million light years on each side. Both normal and dark matter are dealt with, particularly the gravitational effect that dark matter has on normal matter. Using this data, Haider and his team noticed something very interesting about the distribution of matter in the cosmos.Essentially, they found that about 50% of the total mass of the Universe is compressed into a volume of 0.2%, consisting of the galaxies we see. A further 44% is located in the enveloping filaments, consisting of gas particles and dust. The remaining 6% is located in the empty spaces that fall between them (aka. the voids), which make up 80% of the Universe.However, a surprising faction of this normal matter (20%) appears to have been transported there, apparently by the supermassive black holes located at the center of galaxies. The method for this delivery appears to be in how black holes convert some of the matter that regularly falls towards them into energy, which is then delivered to the sounding gas, leading to large outflows of matter.These outflows stretch for hundreds of thousands of lights years beyond the host galaxy, filling the void with invisible mass. As Dr. Haider explains, these conclusions supported by this data are rather startling. "This simulation," he said, "one of the most sophisticated ever run, suggests that the black holes at the center of every galaxy are helping to send matter into the loneliest places in the universe. What we want to do now is refine our model, and confirm these initial findings."The findings are also significant because they just may offer an explanation to the so-called "missing baryon problem". In short, this problem describes how there is an apparent discrepancy between our current cosmological models and the amount of normal matter we can see in the Universe. Even when dark matter and dark energy are factored in, half of the remaining 4.9% of the Universe's normal matter still remains unaccounted for.For decades, scientists have been working to find this "missing matter", and several suggestions have been made as to where it might be hiding. For instance, in 2011, a team of students at the Monash School of Physics in Australia confirming that some of it was in the form of low-density, high energy matter that could only be observed in the x-ray wavelength.https://youtu.be/NjSFR40SY58 In 2012, using data from the Chandra X-ray Observatory, a NASA research team reported that our galaxy, and the nearby Large and Small Magellanic Clouds, were surrounded by an enormous halo of hot gas that was invisible at normal wavelengths. These findings indicated that all galaxies may be surrounded by mass that, while not visible to the naked eye, is nevertheless detectable using current methods.And just days ago, researchers from the Commonwealth Scientific and Industrial Research Organization (CSIRO) described how they had used fast radio bursts (FRBs) to measure the density of cosmic baryons in the intergalactic medium - which yielded results that seem to indicate that our current cosmological models are correct.Factor in all the mass that is apparently being delivered to the void by supermassive black holes, and it could be that we finally have a complete inventory of all the normal matter of the Universe. This is certainly an exciting prospect, as it means that one of the greatest cosmological mysteries of our time could finally be solved.Now if we could just account for the "abnormal" matter in the Universe, and all that dark energy, we'd be in business! Further Reading: Royal Astronomical SocietyThe post Are Supermassive Black Holes Hiding Matter? appeared first on Universe Today.
Incredible Hand-Drawn Animations Explain How Spacecraft Work 
Freelance animator and storyboard artist Stanley VonMedvey has started using his remarkable talents to create short videos to explain a pretty complex topic: how spacecraft work. He's made two so far and they are wonderfully concise, clear and easy to understand. Plus his hand-drawn animations are incredible.Here's the first one that caught my eye, about the space shuttle and the concept of reusability: VonMedvey describes himself as "completely obsessed with and fascinated by space exploration," and he wants to share what he's learned over the years about spaceflight.He'd like the opportunity and resources to make more videos, and has started a Patreon page to help in this process. Right now, he creates the videos on his own (using the time-honored home-recording technique of draping a blanket over his head) in his home officee."I'd like to make a lot more videos," he writes on Patreon, "explaining things like Hohmman transfers and laser propulsion and the construction techniques of O'Neill cylinders. I want to make long form videos (2-3 minutes) that explain a general idea, and short form videos (30 seconds) that cover a single word, like "ballistics" or "reaction control".The second video he's done covers expendable launch vehicles: Enjoy these great videos and if you'd like to see more, consider supporting his work. See more of his drawings at his website.The post Incredible Hand-Drawn Animations Explain How Spacecraft Work appeared first on Universe Today.
Messier 5 (M5) – The NGC 5904 Globular Cluster 
In the late 18th century, Charles Messier was busy hunting for comets in the night sky, and noticed several "nebulous" objects. After initially mistaking them for the comets he was seeking, he began to compile a list of these objects so other astronomers would not make the same mistake. Known as the Messier Catalog, this list consists of 100 objects, consisting of distant galaxies, nebulae, and star clusters.Among the many famous objects in this catalog is the M5 globular star cluster (aka. NGC 5904). Located in the galactic halo within the Serpens Constellation, this cluster of stars is almost as old as the Universe itself (13 billion years)! Though very distant from Earth and hard to spot, it is a favorite amongst amateur astronomers who swear by its beauty. Description: At 13 billion years of age, M5 is believed to be one of the oldest globular clusters in our galaxy (over twice the age of our Solar System). Located 24,500 light years from Earth, it is home to more than 100,000 stars, with some estimates saying it has as many as 500,000. Of these, 105 variable stars call M5 home, as does a dwarf nova.The cluster is also one of the largest known, measuring 165 light-years in diameter and exerting a gravitational influence over a radius of 200 light-years. The brightest and most easily observed variable star in M5 - Cepheid Variable 42 - changes from magnitude 10.6 to 12.1 in a period of just under 26.5 days. Amateur astronomers are encouraged to keep an eye out for it. Interestingly enough, M5 is also home to two millisecond pulsars, which were also discovered in 1997 by S. B. Anderson et al. over a five year period of observations. History of Observation: Gottfried Kirch and his wife Maria were the first to make a recorded observation of M5 on May 5th, 1702. While searching from comets, they stumbled across a huge, bright object that they considered to be a "nebulous star." On May 23rd, 1764, Charles Messier found it independently and labeled it as M5. As he recorded of it at the time: "Beautiful Nebula discovered between the Balance [Libra] & the Serpent [Serpens], near the star in the Serpent, of 6th magnitude, which is the 5th according to the Catalog of Flamsteed [5 Ser]: it doesn't contain any star; it is round, & one sees it very well, in a fine [clear dark] sky, with an ordinary refractor of 1-foot." In 1771, while compiling the first edition of the Messier Catalog, he described the object and his observations of it in more detail: "The night of May 23 to 24, 1764, I have discovered a beautiful nebula in the constellation of Serpens, near the star of sixth magnitude; the fifth according to the catalog of Flamsteed. That nebula doesn't contain any star; it is round, and could have a diameter of 3 arc minutes; one can see it very well, under a good sky, with an ordinary [non-achromatic] refractor of one foot [FL]. I have observed that nebula in the Meridian, and I have compared it to the star Alpha Serpentis. Its position was right ascension 226d 39' 4", and its declination 2d 57' 16" north. On March 11, 1769, at about four o'clock in the morning, I have reviewed that nebula with a good Gregorian telescope of 30 pouces, which magnified 104 times, and I have ensured that it doesn't contain any star." Enter William Herschel, who once again saved the day by seeing this object for what it was. In 1791, he was able to resolve the individual stars and counted up to 200 in this globular cluster. As he wrote of the cluster at the time: "With a magnifying power of 250, it is all resolved into stars: they are very close, and the appearance is beautiful. With 600, perfectly resolved. There is a considerable star not far from the middle; another not far from one side, but out of the cluster; another pretty bright one; a great number of small ones. Here we have a case where the penetrating power of 20 fell short, when 29 resolved the nebula completely. This object requires also great magnifying power to shew the stars of it well; but that power had before been tried, in the 7-feet, as far as 460, without success, and could only give an indication of its being composed of stars; whereas the lower magnifying power of 250, with a greater penetrating power, in the 10-feet instrument, resolved the whole nebula into stars. I counted about 200 of them. The middle of it is so compressed that it is impossible to distinguish the stars." Locating Messier 5: Finding Messier Object 5 in binoculars is much like finding M3 - the key is the Arcturus star and the secondary star hop is Antares. You'll find M5 about 1/3 the distance between Alpha Bootes and Alpha Scorpii. For finderscopes, place Arcturus in the center and look for bright 109 and 110 Virginis to the southwest. To the east you'll see a small triangle of stars - aim there.Under ideal viewing conditions (i.e. where light pollution is not an issue), M5 can be spotted with the naked eye. It will appear as a faint point of light, located about 5° to the south-east (or 30 minutes to the east) of Alpha Serpentis (aka. Unukalhai). Using binoculars, spotting M5 is easy since it will appear quite bright, even under urban skies. However, it will be difficult to resolve because it is so dense.Small telescopes will also have difficulty resolving this globular cluster, but will begin to pick out edge stars and notice that its shape is not quite round. Larger aperture telescopes will easily begin resolution and notice that nearby 5 Serpentis is also a double star.For your convenience, here are the quick facts for Messier 5: Object Name: Messier 5 Alternative Designations: NGC 5904 Object Type: Class V Globular Cluster Constellation: Serpens Right Ascension: 15 : 18.6 (h:m) Declination: +02 : 05 (deg:m) Distance: 24.5 (kly) Visual Brightness: 5.6 (mag) Apparent Dimension: 23.0 (arc min )Enjoy your observations, and keep watching for Variable 42!We have written many interesting articles about Messier Objects here at Universe Today. Here's Tammy Plotner's Introduction to the Messier Objects, M1 – The Crab Nebula, and David Dickison's articles on the 2013 and 2014 Messier Marathons.Be to sure to check out our complete Messier Catalog.For more information, check out the SEDS Messier Database. The post Messier 5 (M5) – The NGC 5904 Globular Cluster appeared first on Universe Today.
SpaceX Resets Launch of Upgraded Falcon 9 Rocket for Serene Sunday Sunset on Feb. 28 – Watch Live 
CAPE CANAVERAL AIR FORCE STATION, FL - Following a pair of back to back launch scrubs this week on Wednesday and Thursday due to rocket fueling issues with the liquid oxygen propellant, SpaceX has reset the blast off of their upgraded Falcon 9 rocket - carrying the commercial SES-9 television and communications satellite - to coincidentally coincide with a serene sunset on Sunday, Feb. 28.Spectators have flocked to the Florida space coast in hopes of catching a glimpse of what could prove to be a spectacular evening streak to orbit after miserable mid-week weather finally departed the sunshine state in favor of glorious blue skies - to the delight of everyone!SpaceX engineers are now targeting liftoff of the Cape's first Falcon 9 launch of 2016 for 6:46 p.m. EST from SpaceX's seaside Space Launch Complex 40 on Cape Canaveral Air Force Station, Fla. at the opening of a 97-minute launch window.The first launch scrub on Wednesday was called some 45 minutes before launch."Out of an abundance of caution, the team opted to hold launch for today to ensure liquid oxygen temperatures are as cold as possible in an effort to maximize performance of the vehicle," SpaceX said in a statement."The rocket and spacecraft were otherwise nominal. "The Falcon 9 remains healthy in advance of SpaceX and SES's mission to deliver the SES-9 satellite to Geostationary Transfer Orbit."The second scrub was called at 1 minute forty seconds before T zero when engineers were concerned about aspects of the liquid oxygen fuel loading and internal temperatures."Countdown held for the day. Teams are reviewing the data and next available launch date," tweeted SpaceX post scrub.SpaceX is cooling the liquid oxygen propellant in the upgraded Falcon 9 to lower temperatures compared to the rockets prior version, in order to increase its density and provide more fuel aboard the rocket for the engines to burn. Both stages of the 229 foot tall Falcon 9 are fueled by liquid oxygen and RP-1kerosene which burn in the Merlin engines. Air Force meteorologists are predicting an almost unheard of >95% percent chance of favorable weather conditions at launch time Sunday - which could result in an absolutely spectacular view as Falcon roars off the launch pad thunders to space, if all goes well.The only potential concern at this time is for cumulus clouds associated with onshore flow.A live webcast will be available at SpaceX.com/webcast beginning about 20 minutes before liftoff, at approximately 6:26 p.m. EST on Sunday, Feb. 28.The launch window closes at approximately 8:23 p.m. EST.The weather prognosis changes only slightly to 90 percent GO on Monday, again with a concern for cumulus clouds.If needed, SpaceX has a backup launch opportunity reserved on the Eastern range for Monday, Feb. 29 at approximately the same time at 6:46 p.m. EST.The goal of Sunday's launch is to boost the commercial SES-9 television and communications satellite to a Geostationary Transfer Orbit (GTO). The satellite will be deployed approximately 31 minutes after liftoff.The commercial launch was contracted by the Luxembourg based SES, a world-leading satellite operator. SES provides satellite-enabled communications services to broadcasters, Internet service providers, mobile and fixed network operators, and business and governmental organizations worldwide using its fleet of more than 50 geostationary satellites.Watch for Ken's onsite launch reports direct from Cape Canaveral Air Force Station in Florida.Stay tuned here for Ken's continuing Earth and planetary science and human spaceflight news. Ken Kremer………….Learn more about SpaceX Falcon 9 rocket, ULA Atlas rocket, Orbital ATK Cygnus, ISS, Boeing, Space Taxis, Mars rovers, Orion, SLS, Antares, NASA missions and more at Ken's upcoming outreach events:Feb 27/28: "SpaceX, ULA, SLS, Orion, Commercial crew, Curiosity explores Mars, Pluto and more," Kennedy Space Center Quality Inn, Titusville, FL, evenings The post SpaceX Resets Launch of Upgraded Falcon 9 Rocket for Serene Sunday Sunset on Feb. 28 – Watch Live appeared first on Universe Today.
Missing Matter Found! Fast Radio Bursts Confirm Cosmological Model 
In July of 2012, researchers at the CERN laboratory made history when they announced the discovery of the Higgs Boson. Though its existence had been hypothesized for over half a century, confirming its existence was a major boon for scientists. In discovering this one particle, the researchers were also able to confirm the Standard Model of particle physics. Much the same is true of our current cosmological model.For decades, scientists been going by the theory that the Universe consists of about 70% dark energy, 25% dark matter and 5% "luminous matter" - i.e. the matter we can see. But even when all the visible matter is added up, there is a discrepancy where much of it is still considered "missing". But thanks to the efforts of a team from the Commonwealth Scientific and Industrial Research Organization (CSIRO), scientists now know that we have it right. This began on April 18th, 2015, when the CSIRO's Parkes Observatory in Australia detected a fast radio burst (FRB) coming from space. An international alert was immediately issued, and within a few hours, telescopes all around the world were looking for the signal. The CSIRO team began tracking it as well with the Australian Telescope Compact Array (ATCA) located at the Paul Wild Observatory (north of Parkes).With the help of the National Astronomical Observatory of Japan's (NAOJ) Subaru telescope in Hawaii, they were able to pinpoint where the signal was coming from. As the CSIRO team described in a paper submitted to Nature, they identified the source, which was an elliptical galaxy located 6 billion light years from Earth.This was an historic accomplishment, since pinpointing the source of FRBs have never before been possible. Not only do the signals last mere milliseconds, but they are also subject to dispersion - i.e. a delay caused by how much material they pass through. And while FRBs have been detected in the past, the teams tracking them have only been able to obtain measurements of the dispersion, but never the signal's redshift.Redshift occurs as a result of an object moving away at relativistic speeds (a portion of the speed of light). For decades, scientists have been using it to determine how fast other galaxies are moving away from our own, and hence the rate of expansion of the Universe. Relying on optical data obtained by the Subaru telescope, the CSIRO team was able to obtain both the dispersion and the redshift data from this signal.https://www.skatelescope.org/wp-content/uploads/2016/02/FRBs.FinalCandidate5-HD.mp4As stated in their paper, this information yielded a "direct measurement of the cosmic density of ionized baryons in the intergalactic medium". Or, as Dr. Simon Johnston - of the CSIRO's Astronomy and Space Science division and the co-author of the study - explains, the team was not only to locate the source of the signal, but also obtain measurements which confirmed the distribution of matter in the Universe."Until now, the dispersion measure is all we had," he said. "By also having a distance we can now measure how dense the material is between the point of origin and Earth, and compare that with the current model of the distribution of matter in the Universe. Essentially this lets us weigh the Universe, or at least the normal matter it contains."Dr. Evan Keane of the SKA Organization, and lead author on the paper, was similarly enthused about the team's discovery. "[W]e have found the missing matter," he said. "It's the first time a fast radio burst has been used to conduct a cosmological measurement."As already noted, FRB signals are quite rare, and only 16 have been detected in the past. Most of these were found by sifting through data months or years after the signal was detected, by which time it would be impossible for any follow-up observations. To address this, Dr. Keane and his team developed a system to detect FRBs and immediately alert other telescopes, so that the source could be pinpointed.It is known as the Square Kilometer Array (SKA), an international effort led by the SKA Organization to build the world's largest radio telescope. Combining extreme sensitivity, resolution and a wide field of view, the SKA is expected to trace many FRBs to their host galaxies. In so doing, it is hoped the array will provide more measurements confirming the distribution of matter in the Universe, as well as more information on dark energy.In the end, these and other discoveries by the SKA could have far-reaching consequences. Knowing the distribution of matter in the universe, and improving our understanding of dark matter (and perhaps even dark energy) could go a long way towards developing a Theory Of Everything (TOE). And knowing how all the fundamental forces of our universe interact will go a long way to finally knowing with certainty how it came to be.These are exciting time indeed. With every step, we are peeling back the layers of our universe! Further Reading: CSIRO, SKA Organization, Nature.The post Missing Matter Found! Fast Radio Bursts Confirm Cosmological Model appeared first on Universe Today.
Spotlight On Pluto's Frozen Polar Canyons 
Pluto's frozen nitrogen custard "heart" has certainly received its share of attention. Dozens of wide and close-up photos homing on this fascinating region rimmed by mountains and badlands have been relayed back to Earth by NASA's New Horizons probe after last July's flyby. For being only 1,473 miles (2,370 km) in diameter, Pluto displays an incredible diversity of landscapes.This week, the New Horizons team shifted its focus northward, re-releasing an enhanced color image of the north polar area that was originally part of a high-resolution full-disk photograph of Pluto. Inside of the widest canyon, you can trace the sinuous outline of a narrower valley similar in outward appearance to the Moon's Alpine Valley, cut by a narrow, curvy rill that once served as a conduit for lava.We see multiple canyons in Pluto's polar region, their walls broken and degraded compared to canyons seen elsewhere on the planet. Signs that they may be older and made of weaker materials and likely formed in ancient times when Pluto was more tectonically active. Perhaps they're related to that long-ago dance between Pluto and its largest moon Charon as the two transitioned into their current tidally-locked embrace.In the lower right corner of the image, check out those funky-shaped pits that resemble the melting outlines of boot prints in the snow. They reach 45 miles (70 km) across and 2.5 miles (4 km) deep and may indicate locations where subsurface ice has melted or sublimated (vaporized) from below, causing the ground to collapse.Notice the variation in color across the landscape from yellow-orange to pale blue. High elevations show up in a distinctive yellow, not seen elsewhere on Pluto, with lower elevations and latitudes a bluish gray. New Horizons' infrared measurements show abundant methane ice across the Lowell Region, with relatively little nitrogen ice. The yellow terrains may be older methane deposits that have been more processed by solar UV light than the bluer terrain. The color variations are especially striking in the area of the collapse pits.Pluto's icy riches include not only methane and nitrogen but also water, which forms the planet's bedrock. NASA poetically refers to the water ice as "the canvas on which (Pluto's) more volatile ices paint their seasonally changing patterns". Recent images made in infrared light shows little or no water ice in the informally named places called Sputnik Planum (the left or western region of Pluto's "heart") and Lowell Regio. This indicates that at least in these regions, Pluto's bedrock remains well hidden beneath a thick blanket of other ices such as methane, nitrogen and carbon monoxide.To delve more deeply into Pluto, visit the NASA's photojournal archive, where you'll find 130 photos (and counting!) of the dwarf planet and its satellites. The post Spotlight On Pluto’s Frozen Polar Canyons appeared first on Universe Today.
The Apus Constellation 
The Southern Hemisphere is replete with beautiful stars and constellations, enough to keep a stargazing enthusiast busy for a lifetime. For countless centuries, the indigenous peoples of South America, South Africa, Australia and the South Pacific have looked up at these stars and drawn inspiration. However, to European astronomers, they remained uncharted and unknown until the 16th century.It was during this time that Flemish astronomer Petrus Plancius designated twelve constellations, using asterisms found in the southern skies. One such constellation was Apus, a faint constellation in the southern sky that is named for the bird-of-paradise - a beautiful bird that is indigenous to the South Pacific. Today, it is one of the 88 constellations defined by the International Astronomic Union (IAU). Name and Meaning: The name Apus is derived from Greek word apous, which literally means "no feet". The name applies to a species of bird that is indigenous to Indonesia, Papua New Guinea, and Eastern Australia (which was believed at one time to have no feet). Its original name on Plancius' charts was "Apis Indica" - the Latin term for "Indian Bee" (presumably an error for "avis", which means bird).Because of this error, the bordering constellation of Musca was later separated and renamed. The neighboring constellations to Apus are Ara, Chamaeleon, Circinus, Musca, Octans, Pavo, and Triangulum Australe. History of Observation: This faint southern constellation of Apus was one of the original twelve created by Plancius, based on observations provided by Pieter Dirkszoon Keyser and Frederick de Houtman - two Dutch explorers/navigators who mapped the southern sky around Australia between 1595 and 1597.It was included on a celestial globe published in 1597 or 1598 in Amsterdam by Plancius and his associate, Flemish cartographer and engraver Jodocus Hondius. After it's introduction on Plancius' globe, it also appeared in Uranometria, a star atlas published by Johann Bayer - a German celestial catrographer - in 1603.Here, it appeared under the name "Apis Indica". It also grouped with the other members of the "Johann Bayer family" of constellations, all of which appeared in Uranometria. These include Chamaeleon, Dorado, Grus, Hydrus, Indus, Musca, Pavo, Phoenix, Tucana, and Volans. The constellation also appears as part of the Chinese constellations, where it is known as the "Little Wonder Bird".In the 17th century, Ming Dynasty astronomer Xu Guangqi adapted the European southern hemisphere constellations when producing The Southern Asterisms. Combining Apus with some of the stars in Octans, he designated the stars in this area of the night sky into the constellation known as Yìquè ("Exotic Bird"). In 1922, Apus was included by the International Astronomical Union in the list of 88 constellations. Notable Features: Within the Apus constellation, there are 39 stars that are brighter than or equal to apparent magnitude 6.5. The most notable of these is Alpha Apodis. an orange giant star with a magnitude of 3.8, located roughly 411 light years away from Earth. Beta Apodis is also an orange giant, with a magnitude of 4.2. and located 158 light years from Earth. And Gamma Apodis , another orange giant, has a magnitude of 3.9 and is located 160 light years away.Delta Apodis is a binary star system consisting of a red giant and an orange giant. Delta¹ has a magnitude of 4.7 and is located 765 light years away, while Delta² has a magnitude of 5.3 and is located 663 light years away. Then there is Theta Apodis, a variable red giant star with a maximum magnitude of 4.8 and a minimum of 6.1 that is located 328 light years away.NO Apodis is a red giant that varies between magnitudes 5.71 and 5.95 and is located around 883 light-years away from Earth. This star shines with a luminosity that is approximately 2059 times greater than our Sun's and has a surface temperature of 3568 K.Apus is also home to a few Deep Sky Objects. These include the IC 4499 loose globular cluster (shown below), which is located in the medium-far galactic halo and has an apparent magnitude of 10.6. This object is rather unique in that its metallicity readings indicate that it is younger than most other globular clusters in the region.Then there's NGC 6101, a 14th mangitude globular cluster located seven degree north of Gamma Apodis. Last, there is the spiral galaxy IC 4633, which is very faint due to its location well within the Milky Way's nebulous disc. Finding Apus: For binoculars, take a look at Alpha Apodis. This 3.8 magnitude star is located 411 light years away from Earth. Now move on to Delta. It is a wide double star which is two orange 5th-magnitude members separated by 103 arc seconds and an easy split. Or try observing Theta - its a variable star whose brightness ranges from magnitude 4.8 to 6.1 in a period of 109 days.For telescopes, take a look at more difficult binary star Kappa-1 Apodis. The brightest component of this disparate pair has a magnitude of 5.4 and the companion is 12th magnitude, 27 arcseconds away. Need more? Then turn your gaze towards Kappa-2 only 0.63 degrees from Kappa-1. Kappa-1 Apodis is a binary star approximately 1020 light years from Earth. The primary component, Kappa-1 Apodis A, is a blue-white B-type subgiant with a mean apparent magnitude of +5.40. It is classified as a Gamma Cassiopeiae type variable star and its brightness varies from magnitude +5.43 to +5.61. The companion star, Kappa-1 Apodis B, is a 12th magnitude orange K-type subgiant. It is 27 arc seconds from the primary.For larger telescopes, wander off and look at NGC 6101 located about seven degrees north of Gamma. Here we have a small, 14th magnitude globular cluster! If you're really good you can try for spiral galaxy IC 4633. It's so faint it doesn't even have a magnitude listing!We have written many interesting articles about the constellation here at Universe Today. Here is What Are The Constellations?, Triangulum Australe, What Is The Zodiac?, and Zodiac Signs And Their Dates.Be sure to check out The Messier Catalog while you're at it!For more information, check out the IAUs list of Constellations. and the Students for the Exploration and Development of Space page on Apus and Constellation Families. The post The Apus Constellation appeared first on Universe Today.
We Explored Pluto, Now Let's Explore The Nearest Star! 
On July 14th, 2015, the New Horizons space probe made history when it became the first spacecraft to conduct a flyby of the dwarf planet of Pluto. Since that time, it has been making its way through the Kuiper Belt, on its way to joining Voyager 1 and 2 in interstellar space. With this milestone reached, many are wondering where we should send our spacecraft next.Naturally, there are those who recommend we set our sights on our nearest star - particularly proponents of interstellar travel and exoplanet hunters. In addition to being Earth's immediate neighbor, there is the possibility of one or more exoplanets in this system. Confirming the existence of exoplanets would be one of the main reasons to go. But more than that, it would be a major accomplishment! Located 4.3 light years from Earth, the Alpha Centauri system consists of three stars - Alpha Centauri A, B, and C (aka. Proxima Centauri). For many years now, exoplanet hunters have been divided on the issue of whether or not it has a system of planets. This began in February of 2008, when a team of European observers working at the European Southern Observatory's La Silla facility in Chile began searching for a possible exoplanet in orbit of Alpha Centauri B - which was designated Alpha Centauri Bb.Using the Doppler spectroscopy method, they recorded measurements of Alpha Centauri B's radial velocity and color spectrum over a four-year period. They then applied statistical filters to remove known sources of variance to be sure that what they were detecting was indeed a planet, and not background noise.In October of 2012, in an article submitted to the scientific journal Nature, they officially announced the existence of Alpha Centauri Bb. According to the team, the planet was similar in mass to Earth and orbited Alpha Centauri B within its habitable zone (aka. "Goldilocks zone"). This made it the closest Earth-like exoplanet discovered to date.However, three years after the announcement, in October 2015, researchers from the University of Oxford published a paper entitled " Ghost in the Time Series" which indicated that there were flaws in the original analysis. According to the paper, the signal that was observed by the ESO team naturally arose from the "window function" of the original data - aka. it was a ghost signal.However, in March of 2015, the same scientific team published a paper that proposed the existence of other alien world orbiting Alpha Centauri B. Using data from the Hubble Space Telescope, they discovered evidence of a possible transit in front of the B star. If confirmed, this planet would be called Alpha Centauri Bc, and is apparently located too close to its parent star to support life.Hence why scientists like Dr. Debra Fischer - a professor of astronomy at Yale University, and a member of the Planetary Society who has discovered hundreds of exoplanets - are advocating for a mission to the Alpha Centauri system. As she told Universe Today via email: "The Kepler mission demonstrated that almost every star has planets and we have found planets orbiting stars that are in binary systems not too different from Alpha Centauri. It's a good bet that there are planets there that we just have not been able to find yet, given current precision... It will likely take a spacecraft in a low Earth orbit with sufficient measurement precision to detect small rocky planets in the system. Once we find them, then we will be highly motivated to send robotic spacecraft to look for life." Naturally, sending a spaceship to the nearest star system represents a major challenge. As we explained in a recent article - How Long Would It Take To Get To The Nearest Star? - even with our most advanced technology, it still would take thousands of years to reach Alpha Centauri - between 72,000 and 81,000 to be exact. Considering that 3000 to 4000 generations would pass between launch and arrival, that hardly seems worth it.Even reckoning for the fastest speed ever achieved by a spacecraft - 240,000 km/hr (150,000 miles/hr), which was accomplished by the Helios 2 probe in the late 1970s - the trip would still take a whopping 19,000 years. In order to make this trip is a single lifetime, during which the spacecraft could reach Alpha Centauri and radio back its findings, something new and experimental would need to be developed.For decades now, ideas ranging from nuclear-thermal propulsion and solar sails have been considered, and some of these proposals are within the realm of possibility. At the more radical end of things, concepts such as nuclear-pulse spacecraft (i.e. Project Orion), fusion containment (i.e. Project Daedalus, shown above) and fusion ramjets have been suggested - ideas that, while possible, would be incredibly expensive to build.And whereas some of these concepts are feasible in the near-term (and using current technology) others are still very much in the theoretical phase, like the Alcubierre "Warp" Drive. Others still, such as the Radio Frequency Cavity Thruster (aka. the Cannae, or EM Drive), have been tested, but not to satisfaction of many in the scientific community.But as Fischer explains, these sorts of challenges have not stopped us before. And there are several options on the table, the development of which could have beneficial applications here on Earth."When you study the energy requirements, it is a daunting goal," she said. "But needing to beat the odds has never stopped us before. We would need to figure out how to accelerate a swarm of networked robotic spacecraft so that they can reach this star system in something like 40 years. "We will have to build receivers with the sensitivity to pick up messages from the Alpha Cen bots. The pathway to solving those questions will have technology spinoffs as impactful as cell phones, lap tops, or GPS."Regardless of the destination, any bold new step in the field of space exploration will have to involve serious planning and careful consideration. Now that we have effectively explored the Solar System, reaching beyond will be a major challenge. But as the history of space exploration teaches us, accepting a major challenge is a great way to bring out the very best in us.Even when the goal seems insurmountable at first glance, working towards it can lead to many great and interesting breakthroughs, some of which have far-reaching benefits. As Fischer added, setting Alpha Centauri as our next goal is every bit as ambitious as our ancestors decision to go to the Moon, and offers similar rewards."The exploration of Alpha Centauri is a grand vision for humanity," she said. "In the 1960's, we sent Apollo missions to explore the moon, and humanity just took another big leap with the New Horizons mission, traveling to the outermost reaches of our solar system. Sending a mission to Alpha Centauri could be the next big stepping stone."Here's hoping some of our more radical ideas start bearing fruit in the coming years. Otherwise, any missions to Alpha Centauri will be very "slow boat" in nature, and I for one would like to live to see what's really there! The post We Explored Pluto, Now Let’s Explore The Nearest Star! appeared first on Universe Today.
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