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    #46

    Star Gazing Live on BBC2 with Brian COx and Dara O Briain......

    edit.... and hubba hubba... Liz Bonnin is on it too..... bonus....
    He was as lame as a duck. Not the metaphorical lame duck either, but a real duck that was actually lame. Maybe from stepping on a land mine or something.

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      #47
      Thanks for link Luckyducker. Breathtaking images
      Has Fineen put Johnny down yet?

      Comment


        #48
        You're welcome. Nice avatar![img]smileys/smile.gif[/img]

        Comment


          #49


          Partial eclipse this morning as the moon passes in front of the rising sun.


          More details here.

          Comment


            #50
            Too cloudy for any chance here
            Always

            Comment


              #51
              BBC stargazing live. Great stuff despite Rossy's interventions and Liz's superlatives. Public service broadcasting at its best.
              Life just kind of empties out, less a deluge than a drought...

              Comment


                #52
                missed that stargazing programme

                i think they might have mentioned this but would be incredible to experience this:
                It is possible that the Eta Carinae hypernova or supernova, when it occurs, could affect Earth, about 7,500 light years away. It is unlikely, however, to affect terrestrial lifeforms directly, as they will be protected from gamma rays by the atmosphere, and from some other cosmic rays by the magnetosphere. The damage would likely be restricted to the upper atmosphere, the ozone layer, spacecraft, including satellites, and any astronauts in space, although a certain few[who?] claim that radiation damage to the upper atmosphere would have catastrophic effects as well. At least one scientist has claimed that when the star explodes, "it would be so bright that you would see it during the day, and you could even read a book by its light at night".[25] A supernova or hypernova produced by Eta Carinae would probably eject a gamma ray burst (GRB) out on both polar areas of its rotational axis. Calculations show that the deposited energy of such a GRB striking the Earth's atmosphere would be equivalent to one kiloton of TNT per square kilometer over the entire hemisphere facing the star with ionizing radiation depositing ten times the lethal whole body dose to the surface.[26] This catastrophic burst would probably not hit Earth, though, because the rotation axis does not currently point towards our solar system. If Eta Carinae is a binary system, this may affect the future intensity and orientation of the supernova explosion that it produces, depending on the circumstances.[10]

                "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

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                  #53

                  Originally posted by Paddy Whac

                  Partial eclipse this morning as the moon passes in front of the rising sun.


                  More details here.
                  very sloppy. There is no such thing as a solar eclipse, it's an occultation. It's where we get the word occult from

                  Comment


                    #54
                    Astronomers have discovered the smallest planet outside our solar system, and the first that is undoubtedly rocky like Earth.

                    Measurements of unprecedented precision have shown that the planet, Kepler 10b, has a diameter 1.4 times that of Earth, and a mass 4.6 times higher.

                    However, because it orbits its host star so closely, the planet could not harbour life.

                    The discovery has been hailed as "among the most profound in human history".

                    The result was announced at the 217th annual meeting of the American Astronomical Society in Seattle, US, by Nasa's Kepler team.

                    The Kepler space telescope, designed to look for the signs of far-flung planets, first spotted the planet 560 light years away, alongside hundreds of other candidate planets.

                    Kepler relies on the "transiting" technique, which looks for planets that pass between their host star and Earth.

                    A tiny fraction of the star's light is blocked periodically, giving a hint that the star has a planet orbiting it.

                    The radius of the planet correlates to exactly how much light is blocked when it passes.

                    Follow-up measurements by a telescope at the Keck observatory in Hawaii confirmed the find of Kepler 10b by measuring how the planet pulls to and fro on its parent star as it orbits.

                    These measurements also bore out the fact that the parent star was about eight billion years old - a grandfather among stars of its type.

                    Crucially, this meant that the star was free of the optical and magnetic activity that have introduced some uncertainty into the measurements of previous candidates for rocky exoplanets, such as Corot-7b, announced in early 2009.
                    Ever-expanding fields

                    This cosmic dance causes tiny changes in the colour of the starlight that is measured by telescopes.


                    However, what completed the suite of measurements for the Kepler team was the use of asteroseismology - a study of distant stars that is akin to the study of earthquakes on the Earth.

                    The oscillations that occur within a star - as within the Earth - affect the frequencies of the light that the star emits in a telltale sign of the star's size.

                    With the size of the host star, the details of the planet's and star's mutual dance, and the planet's radius, the density of the planet can be calculated.

                    "All of our very best capabilities have converged on this one result and they all converge to form a picture of this planet," said Natalie Batalha, a San Jose State University professor of astrophysics who helps lead the Kepler science mission for Nasa.
                    Hot rocks

                    Professor Batalha told BBC News that the result was unique in an ever-expanding field of exoplanet discoveries, with smaller and smaller exoplanets discovered as experimental methods improve.

                    "We're always pushing down toward smaller and less massive, so it's natural that we're arriving there," she said.

                    "But perhaps what's not so natural is that we've pinned down the properties of this planet with such fantastic accuracy that we're able to say without a doubt that this is a rocky world, something that you could actually stand on."

                    One could, that is, if it were not so close to its host star that its daytime temperature exceeds 1,300C - so Kepler 10b is not a sensible candidate to host life. However, as Professor Batalha explained, it is a significant step in Kepler's mission.

                    "We want to know if we're alone in the galaxy, simply put - and this is one link in the chain toward getting to that objective.

                    "First we need to know if planets that could potentially harbour life are common, and we don't know if that's true - that's what Kepler is aiming to do."

                    A pioneer of the hunt for exoplanets, Geoffrey Marcy, from the University of California Berkeley, said that Kepler 10b represented "a planetary missing link, a bridge between the gas giant planets we've been finding and the Earth itself, a transition... between what we've been finding and what we're hoping to find".

                    "This report... will be marked
                    "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

                    Comment


                      #55


                      http://www.bbc.co.uk/news/science-environment-12167011


                      dont know how i missed this:


                      http://www.google.com/sky/
                      "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

                      Comment


                        #56
                        <a href="http://www.rte.ie/news/2011/0119/meteorite.html" target="_blank">
                        Search on for 'huge' meteorite</a>


                        The search is on for fragments of a meteorite which blazed across Irish skies yesterday evening.

                        The meteor - described as 'huge' by Astronomy Ireland - is known as a fireball.

                        Astronomy Ireland says it is likely to be a piece of a comet or asteroid that passed near Earth's orbit sometime in the past.

                        It appeared in the moonlit sky at approximately 6pm, or shortly after.

                        If it survived the fall to Irish soil, keen treasure hunters may fetch hundreds of euro per gram of the meteorite if found.

                        Astronomy Ireland says people all over the country are reporting sightings of a meteorite or fireball which blazed across Irish skies at around 6pm yesterday.

                        The club's chairman, David Moore, is appealing for anyone who operates CCTV cameras to check footage which may have recorded the event.

                        Astronomy Ireland says there were three major fireball events recorded in Ireland last year - in February, September and November.

                        No fragments of any of these meteorites have been found.

                        © RTÉ

                        Comment


                          #57
                          http://spaceweather.com/

                          Great site for asteroids etc....

                          "Syrana" on de Villiers "A step, a hand off and two more defenders beaten on the line and the third try was in the bag. It's amazing what a world class inside centre can do when you play him at inside centre!"

                          Comment


                            #58


                            Astronomers have identified some 54 new planets where conditions may be suitable for life.


                            Five of the candidates are Earth-sized.


                            The announcement from the Kepler space telescope team brings the total number of exoplanet candidates they have identified to more than 1,200.


                            The data release also confirmed a unique sextet of planets around a single star and 170 further solar systems that include more than one planet circling far-flung stars.


                            The Kepler telescope was conceived to hunt for exoplanets, staring into a small, fixed patch of the sky in the direction of the constellations Cygnus and Lyra.


                            It looks for the minuscule dimming of light that occurs when an exoplanet passes in front of its host star. Kepler spots "candidate" planets, which typically are confirmed by ground-based observations to confirm their existence.


                            In just its first few months of operation, as a paper posted to the Arxiv server reports, Kepler has spotted 68 Earth-sized candidates, 288 so-called "super-Earths" that are up to twice Earth's size, 662 that are Neptune-sized, and 184 that are even larger.


                            Continue reading the main story
                            THE KEPLER SPACE TELESCOPE

                            Stares fixedly at a patch corresponding to 1/400th of the sky
                            Looks at more than 150,000 stars
                            In just four months of observations has found 1,235 candidate planets
                            Among them, it has spotted the first definitively rocky exoplanet
                            It has found 68 Earth-sized planets, five of which are in the "habitable zone"
                            Bill Borucki talks about Kepler
                            On Wednesday, members of the team announced it had confirmed the Kepler-11 solar system, comprising six large exoplanets tightly circling an eight billion-year-old star that lies about 2,000 light-years away.


                            "The fact that we've found so many planet candidates in such a tiny fraction of the sky suggests there are countless planets orbiting sun-like stars in our galaxy," said William Borucki, who heads Kepler's science programme at Nasa's Ames Research Center.


                            "We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone, some of which could have moons with liquid water."


                            The bountiful nature of the data from just a few months of observing time from Kepler makes profound suggestions about the preponderance of exoplanets in general, and about the existence of multiple planets around single stars in particular.


                            In a separate paper, team members outlined how the Kepler candidates include 115 stars that host a pair of planets, 45 with three, eight stars with four, one with five planets, and Kepler-11, which hosts six.


                            "Even in first four months of Kepler data, a rich population of multiples appeared, and we recognised this was going to be a very important discovery," David Latham, of the Harvard-Smithsonian Center for Astrophysics, told BBC News.
                            "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

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                              #59



                              Stereo satellites move either side of Sun


                              Two US spacecraft have moved either side of the Sun to establish observing positions that should return remarkable new information about our star.


                              Launched in 2006, the Stereo satellites have gradually been drifting apart - one in front of the Earth in its orbit, the other lagging behind.


                              On Sunday, Nasa said the spacecraft had arrived at points that put the Sun directly between them.


                              It will give solar physicists the first 360-degree view of our star.


                              Stereo is short for Solar Terrestrial Relations Observatory.


                              The mission is studying the Sun's great explosive events that hurl billions of tonnes of charged particles at Earth - events that can disrupt power grids and satellites.


                              These Coronal Mass Ejections (CMEs), as they are known, can also be hazardous to astronauts in space


                              Professor Richard Harrison of the STFC Rutherford Appleton Laboratory, UK, is an investigator on the project.


                              He told BBC News: "By being away from the Sun-Earth line, you can look back at the space between the Sun and the Earth and see any of these clouds, these coronal mass ejections that are thrown out of the Sun and are coming our way - you can even see these things passing over the Earth. Those are the key to what Stereo's all about."


                              The two spacecraft will continue to move further apart, heading toward each other on the opposite side of the Sun from the Earth; this means that the full view provided by the two craft will fade, leaving a growing region behind the Sun - on the Earth side - that they do not see.


                              However, the Solar Dynamics Observatory, launched in Earth orbit a year ago, will remain fixed on the Sun, providing the missing piece of the puzzle.


                              Achieving an all-round-view view of the Sun will be key to understanding what drives the complex processes in the Sun, believes Professor Harrison.


                              "You really see it with these widely separated regions of the Sun's atmosphere that are connected magnetically, showing activity at the same time, or causing activity somewhere else," he explained.


                              "These things stress to us that you can't really study the Sun in great detail just by looking at a bit of it, any more than you could understand the brain by looking at a bit of it or study the Earth's polar regions by looking at the equator. You need this global view to really piece the jigsaw puzzle together."


                              Scientists suspect that activity on the Sun can on occasions go global, with eruptions on opposite sides of the Sun triggering and feeding off one another. With the Stereo craft in their new positions, this phenomenon can now be studied.


                              Stereo is already being used to improve "space weather" forecasts for airlines, power companies, satellite operators, and other customers


                              "Some people don't know their easy lives... I wouldn't be so ungrateful" - Fiacre Ryan - #AutismAndMe

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                                #60
                                Is Class X flash first warning of 2012 solar storm?


                                A POWERFUL solar eruption that has already disturbed radio communications in China could disrupt electrical power grids and satellites used on Earth in the next days, NASA said.

                                The massive sunspot, which astronomers say is the size of Jupiter, is the strongest solar flare in four years, NASA said yesterday.

                                The Class X flash - the largest such category - erupted on Tuesday, according to the US space agency.

                                "X-class flares are the most powerful of all solar events that can trigger radio blackouts and long-lasting radiation storms," disturbing telecommunications and electric grids, NASA said.

                                Astronomers have been predicting a solar cycle known as Solar maximum, predicted to hit with full force in 2012, could be one of the most damaging on record.

                                Similar storms back in 1859 and 1921 caused worldwide chaos, wiping out telegraph wires on a massive scale, but the potential for damage in the digital era could be much greater.

                                A recent report by the National Academy of Sciences found that if a similar storm occurred today, it could cause “$1 to 2 trillion in damages to society's high-tech infrastructure and require four to 10 years for complete recovery”.

                                On Tuesday, NASA's Solar Dynamics Observatory saw a large coronal mass ejection (CME) associated with the flash that is blasting toward Earth at about 900km per second, it said.

                                The charged plasma particles were expected to reach the planet's orbit tonight.

                                The flare spread from Active Region 1158 in the sun's southern hemisphere, which had so far lagged behind the northern hemisphere in flash activity. It followed several smaller flares in recent days.

                                "The calm before the storm," read a statement on the US National Weather Service Space Weather Prediction Service.

                                "Three CMEs are enroute, all a part of the Radio Blackout events on February 13, 14, and 15 (UTC). The last of the three seems to be the fastest and may catch both of the forerunners about mid to late ... February 17."

                                Geomagnetic storms usually last 24 to 48 hours, "but some may last for many days", read a separate NWS statement.

                                "Ground to air, ship to shore, shortwave broadcast and amateur radio are vulnerable to disruption during geomagnetic storms. Navigation systems like GPS can also be adversely affected."

                                The China Meteorological Administration reported that the solar flare had jammed shortwave radio communications in southern China.

                                It said the flare caused "sudden ionospheric disturbances" in the atmosphere above China, and warned there was a high probability that large solar flares would appear over the next three days, the official Xinhua news agency reported.

                                Another previous major disturbance of the Earth's electric grid from a solar incident, in 1973, a magnetic storm caused by a solar eruption plunged six million people into darkness in Canada's eastern-central Quebec province.

                                The British Geological Survey said meanwhile that the solar storm would result in spectacular Northern Lights displays.

                                One coronal mass ejection (CME) arrived on February 14, "sparking Valentine's Day displays of the Northern Lights (aurora borealis) further south than usual".

                                "Two CMEs are expected to arrive in the next 24-48 hours and further... displays are possible some time over the next two nights if skies are clear," it said.

                                The office published geomagnetic records dating back to the Victorian era which it hopes will help in planning for future storms.

                                "Life increasingly depends on technologies that didn't exist when the magnetic recordings began," said Alan Thomson, BGS head of geomagnetism.

                                "Studying the records will tell us what we have to plan and prepare for to make sure systems can resist solar storms," he said.


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