This is a ground-based telescope’s view of the Large Magellanic Cloud, a satellite galaxy of our Milky Way. The inset image, taken by the Hubble Space Telescope, reveals one of many star clusters scattered throughout the dwarf galaxy. The universe is expanding faster than expected, suggesting that astronomers may have to incorporate some new physics into their theories of how the cosmos works, a new study reports. The revised expansion rate is about 10% faster than that predicted by observations of the universe's trajectory shortly after the Big Bang , according to the new research. The study also significantly reduces the probability that this disparity is a coincidence, from 1 in 3,000 to just 1 in 100,000. "This mismatch has been growing and has now reached a point that is really impossible to dismiss as a fluke," study lead author Adam Riess, a professor of physics and astronomy at The Johns Hopkins University in Baltimore, said in a statement . "This is not what we expected," said Riess, who won the Nobel Prize for physics in 2011 (along with Brian Schmidt and Saul Perlmutter) for showing, in the late 1990s, that the universe's expansion is accelerating. It's unclear what's driving this surprising acceleration, but many astronomers invoke a mysterious, repulsive force called dark energy . Related: The Universe: Big Bang to Now in 10 Easy Steps This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All the steps involve building a strong "cosmic distance ladder," by starting with measuring accurate distances to nearby galaxies and then moving to galaxies farther and farther away. This ladder is a series of measurements of different kinds of astronomical objects with an intrinsic brightness that researchers can use to calculate distances. (Image credit: NASA, ESA, and A. Feild (STScI)) In the new study, Riess and his colleagues used the Hubble Space Telescope to study 70 Cepheid variable stars in the Large Magellanic Cloud (LMC), one of the Milky Way's satellite galaxies. Cepheid variables dim and brighten at predictable rates and are therefore "standard candles" that allow astronomers to calculate distances. (Another kind of standard candle, the star explosions known as Type 1a supernovae, enables scientists to measure distances even farther out into space. Riess, Schmidt and Perlmutter's studies of Type 1a supernovae led to their Nobel-winning discovery.) Riess and his team also incorporated observations made by the Araucaria Project, a collaboration involving researchers in the United States, Europe and Chile, who studied various LMC binary star systems, noting the dimming that occurred when one star passed in front of its neighbor. This work provided additional distance measurements, helping the study team to improve their understanding of the Cepheids' intrinsic brightness. The researchers used all of this information to calculate the universe's present-day expansion rate, a value known as the Hubble constant , after American astronomer Edwin Hubble. The new number is about 46.0 miles (74.03 kilometers) per second per megaparsec; one megaparsec is roughly 3.26 million light-years. The uncertainty attached to this number is just 1.9%, the researchers said. That's the lowest uncertainty value to date that has been calculated using this approach — down from about 10% in 2001 and 5% in 2009. The "expected" expansion rate, by contrast, is about 41.9 miles (67.4 km) per second per megaparsec . This projected rate is based on observations that Europe's Planck satellite made of the cosmic microwave background – the light left over from the Big Bang that created the universe 13.82 billion years ago. "This is not just two experiments disagreeing. We are measuring something fundamentally different," Riess said. "One is a measurement of how fast the universe is expanding today, as we see it. The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding," he added. "If these values don’t agree, there becomes a very strong likelihood that we’re missing something in the cosmological model that connects the two eras." The new study was published today (April 25) in The Astrophysical Journal . You can read it for free at the online preprint site arXiv.org .<doc-sep>There is something amiss with the expansion of the Universe; the space between galaxies is stretching – scientists are sure about that – but just how fast is it expanding? New research shows that what scientists predict and what they observe are two different things and measurements calculated of today’s expansion rate do not match the rate that was expected based on how the Universe appeared shortly after the Big Bang over 13 billion years ago. The unit of measurement used to describe the expansion of the Universe is called the Hubble Constant, H 0 , (see notes below*) and the current best direct measurement of the Hubble constant is 74.03 kilometres per second per megaparsec (km/sec/Mpc) – give or take 2.4 km/sec/Mpc, including both random and systematic errors. This means that for every 3.3 million light-years farther away a galaxy is from us, it appears to be moving 74 kilometres (46 miles) per second faster, as a result of the expansion of the Universe. Scientists have previously worked out this value by measuring the light from pulsating stars called Cepheid variables in a neighbouring satellite galaxy known as the Large Magellanic Cloud (LMC). Cepheids vary their brightness in such a dependable and regular way that they have become an important “cosmic distance ladder" to aid scientists determine how far away things are in the Universe. Indeed, this new research uses the same type of object but utilises a different method to calculate the Hubble Constant. Instead of observing one Cepheid at a time with NASA’s Hubble Space Telescope as it makes its 90-minute orbit around Earth, a team of scientists including Nobel laureate Adam Riess of the Space Telescope Science Institute (STScI) and Johns Hopkins University, in Baltimore, Maryland has used Hubble as a "point-and-shoot" camera to snap quick images of the extremely bright pulsating stars, This method means that Hubble’s telescope pointing doesn’t need to be constantly recalibrated and this quick fire method has earned it the title DASH, which stands for Drift And Shift. “These Cepheids are so bright, we only need to observe them for two seconds. This technique is allowing us to observe a dozen Cepheids for the duration of one orbit. So, we stay on gyroscope control and keep 'DASHing' around very fast,” says Reiss. The improved method has now given scientists the most precise value yet of the Hubble Constant. If it all sounds great, it is. No really it is. But herein lies a spanner in the works; the method outlined above and the value it produced are not the only one. Looking at this phenomena from a different angle is the European Space Agency’s Planck mission. Planck has been studying the skies since its launch nearly a decade ago to refine values associated with the cosmic microwave background (CMB). The CMB is relic radiation leftover from the Big Bang and as such gives scientists a look into conditions in the very young Universe. However, when you calculate the Hubble Constant from CMB/Planck data, you get a different figure altogether; 67.4 km/sec/Mpc, with a tiny uncertainty of less than a percent. This latest research by Reiss and team has reduced the uncertainty in their Hubble constant value to an unprecedented 1.9 percent - that is a significant improvement from a previous estimate last year which had the uncertainty set at 2.4 percent. This is equivalent to saying that the discrepancy is only a fluke to 1 in 100,000 (last years estimate was a chance of 1 in 3,000, so a substantial gain from earlier data). In principle these two speed values should agree to within their respective uncertainties, but they don’t and this discrepancy is a lot by scientific standards. Both methods have been thoroughly vetted and no one is quite sure whether differences in measurement techniques are to blame, or whether results from unlucky measurements are the cause. Like many things in life that don’t agree, this discrepancy has caused what cosmologists call a 'tension' – an oddity that still needs explaining. But says Reiss, this disparity could not plausibly occur just by chance. "This mismatch has been growing and has now reached a point that is really impossible to dismiss as a fluke. This is not just two experiments disagreeing. We are measuring something fundamentally different. One is a measurement of how fast the universe is expanding today, as we see it. The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding,” explained Reiss. “If these values don't agree, there becomes a very strong likelihood that we're missing something in the cosmological model that connects the two eras,” he said. So, what could it be that is missing? One explanation proposed by astronomers at Johns Hopkins, is a theory dubbed "early dark energy," and suggests an unexpected appearance of dark energy in the young Universe. This would require dark energy, which is thought to now comprise 70 percent of the Universe's contents, appeared not long after the big bang, that made the Universe expand faster than astronomers had predicted. The existence of this "early dark energy" could account for the tension between the two Hubble constant values, Riess said. Do we really need to add another tier of exotic dark stuff to explain the inconsistency in results? So much uncertainly surrounds the original invisible repulsive force that was first postulated to account for the expansion without adding a third layer to it all. There are others that think such dark energy ideas are now getting too convoluted, and that a much simpler explanation, one that even Einstein considered, should now be given serious consideration; a change in the speed of light, or VSL (Varying Speed of Light) as others know it by. “The ‘tension’ between measurements of the Hubble-Lemaire constant, H 0 , (which is known to be changing over time) shows that old theories of the Universe are missing something. If H 0 was the lower value of 67 km/sec/Mpc, much or all of the so-called acceleration would vanish.<doc-sep>Astrophysicists were surprised to discover that the universe is expanding much faster than expected, potentially needing new physics to find an answer. The Hubble Space Telescope has shed more fascinating light on the universe around us, showing that the cosmos is hurtling away from us at great speed. In a study published to the Astrophysical Journal Letters, a team of researchers led by Nobel laureate and Johns Hopkins University professor Adam Riess detailed how the universe is expanding 9pc faster than previously thought. These measurements reduce the chances the large disparity is an accident from one in 3,000 to only one in 100,000, suggesting that new physics may be needed to better understand the cosmos. “This mismatch has been growing and has now reached a point that is really impossible to dismiss as a fluke. This is not what we expected,” Riess said. To make the discovery, the team analysed light from 70 stars in our neighbouring galaxy, the Large Magellanic Cloud, with a new method that allowed for capturing quick images of these stars. These Cepheid variable stars brighten and dim predictably, making them excellent for measuring intergalactic distances. Crucial to the breakthrough was a vastly improved measurement method called Drift and Shift (DASH). Typically, Hubble would only be able to observe one star every 90-mintue orbit around Earth. However, using DASH, the team used Hubble as a ‘point and shoot’ camera to look at up to a dozen groups of Cepheids compared with just one. These measurements were combined with other observations made by researchers in Chile, the US and Europe that included distance measurements to the Large Magellanic Cloud. This was achieved by observing the dimming of light as one star passes in front of its partner in eclipsing binary star systems. ‘This is not just two experiments disagreeing’ These combined results helped show the team the true Cepheid brightness and ‘tighten the bolts’ of the so-called distance ladder. This is used to determine distances within the universe and calculate the Hubble constant, a value of how fast the cosmos expands over time. The team’s discovery now significantly contradicts findings made by the European Space Agency’s Planck satellite, which drew on data observed 380,000 years after the Big Bang. “This is not just two experiments disagreeing,” Riess explained. “We are measuring something fundamentally different. One is a measurement of how fast the universe is expanding today, as we see it. “The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding. If these values don’t agree, there becomes a very strong likelihood that we’re missing something in the cosmological model that connects the two eras.” With no reason for the discrepancy as of yet, the team is now working to reduce uncertainty from 1.9pc to 1pc. By comparison, in 2001 this uncertainty was 10pc.<doc-sep>A new study led by a Nobel Prize winner found that the universe is younger and expanding faster than scientists thought. Astronomer Adam Riess used measurements from NASA's Hubble Space Telescope to conclude that the universe is expanding 9% faster than previous calculations said. Reiss and other scientists think that both calculations could be right, which means that the rate of the universe's expansion has increased They think that "new physics" may be necessary to explain the difference. Riess also calculated that the universe is between 12.5 billion and 13 billion years old — younger than the previous estimates of between 13.6 billion and 13.8 billion years old. Visit Business Insider's homepage for more stories/ The universe is younger and expanding faster than we thought, a new study found, scientists think we may have to work on new physics as a result. A new study lead by Nobel Prize-winning scientist, Adam Riess, found that the universe is expanding 9% faster than previous calcultions that were based on studying the aftermath of the Big Bang. The study by Riess, an astronomer at Johns Hopkins University, was published in Astrophysical Journal this week, and used new measurements from NASA's Hubble Space Telescope to calculate the new expansion rate, which scientist have theorized for years. But Reiss, and other scientists, think that the expansion rates concluded by both studies could be correct, which means that the rate of the universe's expansion has increased — and they say that "new physics" may be necessary to explain the discrepancy. Reiss said that the universe "is outpacing all our expectations in its expansion, and that is very puzzling." Read more: NASA has discovered that meteoroids are causing water to leak off the moon NASA astrophysicist John Mather, who has also won a Nobel Prize, said that the two different expansion rates could be down to two things, The Associated Press reported: "1. We're making mistakes we can't find yet. 2. Nature has something we can't find yet." But Reiss downplayed the idea that the results could be the result of human error. He said that the "mismatch" between the two rates "has been growing and has now reached a point that is really impossible to dismiss as a fluke," he said. "This is not what we expected." Riess said: "This is not just two experiments disagreeing." NASA's Hubble Space Telescope. NASA/Getty Images "We are measuring something fundamentally different. One is a measurement of how fast the universe is expanding today, as we see it. The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding. If these values don't agree, there becomes a very strong likelihood that we're missing something in the cosmological model that connects the two eras." Read more: A photographer recorded Saturn 'touching' the moon with his smartphone, and the pictures are stunning "It's looking more and more like we're going to need something new to explain this," he said. One theory suggested by Reiss is that the mysterious "dark energy" substance could have sped up the expansion of the universe. University of Chicago astrophysicist Wendy Freedman also said that both calculations seem valid, and that "nobody can find anything wrong at this point" with either of the studies or their results. Using measurements captured though the Hubble telescope, Riess also calculated that the universe is between 12.5 billion and 13 billion years old — younger than the previous estimates of between 13.6 billion and 13.8 billion years old.<doc-sep>
The universe is expanding faster than predicted, new data reveal, indicating that something is missing from the current cosmological model. Researchers led by Nobel laureate Adam Reiss from Johns Hopkins University in the US used a new method of data-gathering from NASA’s Hubble Space Telescope to track the movements of 70 stars in the Large Magellanic Cloud (LMC) – the galaxy next to the Milky Way – to achieve a more tightly constrained measure of their movements. The results were combined with those made by the Araucaria Project, a collaboration between astronomers from institutions in Chile, the US and Europe that is also concerned with refining distance measurements of stars within the LMC. Together, the two sets of results permitted a much more accurate reassessment of what astronomers call the “cosmic distance ladder”, a collection of cascading measures by which distances between celestial objects are calculated. The ladder is used to determine the Hubble Constant – the rate at which the universe expands over time. The findings were then compared to the values derived from observations of the early universe’s expansion, made by the European Space Agency’s Planck satellite. The satellite measured conditions in the universe only about 380,000 years after the Big Bang, from which the initial expansion rate could also be derived. It has long been assumed that the Hubble Constant is, as the name suggests, constant, and that the rate at which the universe is expanding is the same today as it was pretty much 14 billion years ago. The work of Reiss and his team has now blown that certainty away, revealing that the universe is now expanding around 9% faster now than it was in the deep past. The new measurements, the researchers report in The Astrophysical Journal, establish new constraints, and reduce the chance that the readings could be wrong from one in 300 to one in 100,000. “This is not just two experiments disagreeing,” Riess explains. “We are measuring something fundamentally different. One is a measurement of how fast the universe is expanding today, as we see it. “The other is a prediction based on the physics of the early universe and on measurements of how fast it ought to be expanding. If these values don’t agree, there becomes a very strong likelihood that we’re missing something in the cosmological model that connects the two eras.” The Hubble constant is of course a precise function, but there has always existed a degree of uncertainty concerning the accuracy of the data fed into it. The latest results reduce that uncertainty from 10% in 2001 to 1.9% – making the chances that the 9% disparity between the Plank and Hubble data is just a statistical glitch very unlikely. “This mismatch has been growing and has now reached a point that is really impossible to dismiss as a fluke,” says Reiss. “This is not what we expected.” The researchers intend to establish another series of observations to try to reduce the uncertainty in the Hubble Constant input to 1% – and then to close in on why the universe appears to have sped up. A full copy of the paper is available on the preprint server arXiv. Related reading: How quickly is the Universe expanding?