By measuring the energy output from a large portion of the Universe with greater precision than ever before, astronomers have determined that the Universe is gradually fading across all wavelengths. In effect, the Universe is slowly dying.
Credit: ICRAR/GAMA and ESO
An international team of astronomers studying more than 200 000 galaxies has measured the energy generated within a large portion of space more precisely than ever before. This represents the most comprehensive assessment of the energy output of the nearby Universe. They confirm that the energy produced in a section of the Universe today is only about half what it was two billion years ago and find that this fading is occurring across all wavelengths from the ultraviolet to the far infrared. The Universe is slowly dying.
The study involves many of the world's most powerful telescopes, including the European Southern Observatory's VISTA and VST survey telescopes at the Paranal Observatory in Chile. Supporting observations were made by two orbiting space telescopes operated by NASA (GALEX and WISE) and another belonging to the European Space Agency (Herschel). The research is part of the Galaxy And Mass Assembly (GAMA) project, the largest multi-wavelength survey ever put together.
"We used as many space and ground-based telescopes as we could get our hands on to measure the energy output of over 200 000 galaxies across as broad a wavelength range as possible," says Simon Driver, who heads the large GAMA team.
The survey data, released to astronomers this week, includes measurements of the energy output of each galaxy at 21 wavelengths, from the ultraviolet to the far infrared. This dataset will help scientists to better understand how different types of galaxies form and evolve.
All of the energy in the Universe was created in the Big Bang, with some portion locked up as mass. Stars shine by converting mass back into energy as described by Einstein's famous equation E=mc2. The GAMA study sets out to map and model all of the energy generated within a large volume of space today and at different times in the past.
"While most of the energy sloshing around in the Universe arose in the aftermath of the Big Bang, additional energy is constantly being generated by stars as they fuse elements like hydrogen and helium together," says Driver. "This new energy is either absorbed by dust as it travels through the host galaxy or escapes into intergalactic space and travels until it hits something – such as another star, a planet, or, very occasionally, a telescope mirror."
The fact that the Universe is slowly fading has been known since the late 1990s, but this work shows that it is happening across all wavelengths from the ultraviolet to the infrared, representing the most comprehensive assessment of the energy output of the nearby Universe.
"The Universe will decline from here on in, sliding gently into old age. The Universe has basically sat down on the sofa, pulled up a blanket and is about to nod off for an eternal doze," concludes Driver.
The team of researchers hope to expand their work to map energy production over the entire history of the Universe – using a swathe of new facilities, including the world's largest radio telescope, the Square Kilometre Array, which is due to become operational in 2024.
The team presented their findings at the International Astronomical Union XXIX General Assembly in Honolulu, Hawaii, on Monday 10th August.
NASA has announced the discovery of Kepler-452b, an exoplanet that is near-Earth-size and orbiting the habitable zone of a Sun-like star.
This artist's impression compares Earth (left) to the new planet, Kepler-452b, which is about 60 percent larger in diameter (right). Credits: NASA/JPL-Caltech/T. Pyle
NASA's Kepler mission has confirmed the first near-Earth-size planet in the “habitable zone” around a sun-like star. This discovery and the introduction of 11 other new small habitable zone candidate planets mark another milestone on the journey to finding “Earth 2.0.”
The newly discovered Kepler-452b is the smallest planet to date found inside the habitable zone of a G-type star, like our sun. Today's confirmation of Kepler-452b brings the total number of confirmed exoplanets to 1,030.
“On the 20th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet and star which most closely resemble the Earth and our Sun,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This exciting result brings us one step closer to finding an Earth 2.0.”
Kepler-452b is 60 percent larger in diameter than Earth and is considered a super-Earth-size planet. While its mass and composition are not yet determined, previous research suggests that planets of this size have a good chance of being rocky.
While Kepler-452b is somewhat larger than Earth, its orbit is remarkably similar, being only 5 percent longer at 385 days. The planet is just 5 percent farther from its parent star than Earth is from our Sun. The star Kepler-452 has the same temperature as our own sun, is around 20 percent brighter and with a diameter 10 percent larger. Its age is estimated at 6 billion years, which is 1.5 billion years older than our sun.
“We can think of Kepler-452b as an older, bigger cousin to Earth, providing an opportunity to understand and reflect upon Earth’s evolving environment,” said Jon Jenkins, data analysis lead at NASA's Ames Research Centre, California. “It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth. That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet.”
In addition to confirming Kepler-452b, the team has increased the number of new exoplanet candidates by 521 from their analysis of observations conducted from May 2009 to May 2013, raising the number of planet candidates detected by the Kepler mission to 4,696. Candidates require follow-up observations and analysis to verify they are actual planets.
Twelve of the new planet candidates have diameters between one to two times that of Earth, and orbit in their star's habitable zone. Of these, nine orbit stars that are similar to our sun in size and temperature.
“We've been able to fully automate our process of identifying planet candidates, which means we can finally assess every transit signal in the entire Kepler dataset quickly and uniformly,” said Jeff Coughlin, Kepler scientist at the SETI Institute in Mountain View, California, who led the analysis of a new candidate catalogue. “This gives astronomers a statistically sound population of planet candidates to accurately determine the number of small, possibly rocky planets like Earth in our Milky Way galaxy.”
The Kepler-452 system is located 1,400 light-years away in the constellation Cygnus. At the speed of New Horizons, it would take about 25.8 million years to reach there. A research paper reporting NASA's findings has been accepted for publication in The Astronomical Journal.
Through private and international partnerships, the cost of colonising other worlds could be reduced by 90 percent, according to a joint study released by the National Space Society and the Space Frontier Foundation and reviewed by an independent team of NASA experts.
“The Space Frontier Foundation supports and recommends public-private partnerships in all proposed human spaceflight programs in order to reduce costs and enable these missions that were previously unaffordable,” said the Space Frontier Foundation’s Chairman of the Board, Jeff Feige. “This is the way that America will settle the final frontier, save taxpayers money and usher in a new era of economic growth and STEM innovation.”
NSS and SFF call attention to these conclusions from the study:
• Through public-private partnerships, NASA could return humans to the surface of the Moon and develop a permanent lunar base with its current human spaceflight budget.
• Mining fuel from lunar poles and transporting it to lunar orbit for use by other spacecraft reduces the cost of sending humans to Mars and other locations beyond low Earth orbit. These commercial fuel depots in lunar orbit have the potential to cut the cost of sending humans to Mars by more than $10 billion per year.
“NSS congratulates NASA for funding the team at NexGen that discovered how such cost reductions are possible,” said Mark Hopkins, the NSS Executive Committee Chair. “A factor of ten reduction in cost changes everything.”
Recent contracts with Boeing and SpaceX are just one example of how partnerships can work and may help with more ambitious projects in the future. The latter spent only $440 million developing its Falcon 9 rocket and Dragon crew capsule, where NASA would have spent $4 billion. SpaceX has also been developing a reusable rocket that aims to dramatically cut launch costs. Extracting and refining resources on the Moon, rather than having them delivered up from Earth to the lunar surface, could save a great deal of money too. There are many other examples of cost-saving measures. Click here to read the executive summary and here to download the full report.
Planetary Resources, Inc., the asteroid mining company, announced today that its Arkyd 3 Reflight (A3R) spacecraft was deployed successfully from the International Space Station's (ISS) Kibo airlock and has begun its 90-day mission.
The A3R demonstration vehicle will validate several core technologies including the avionics, control systems and software, which the company will incorporate into future spacecraft that will venture into the Solar System and prospect for resource-rich, near-Earth asteroids.
The A3R was launched to the ISS onboard a SpaceX Falcon 9 rocket in April as part of the CRS-6 crew resupply mission. "Our philosophy is to test often, and if possible, to test in space. The A3R is the most sophisticated, yet cost-effective, test demonstration spacecraft ever built. We are innovating on every level from design to launch," said Chris Lewicki, president and chief engineer, Planetary Resources, Inc. "By vertically integrating the system at our facility in Redmond, we are in constant control of every component, including the ones we purchase off the shelf and the others that we manufacture using 3D printers."
Peter H. Diamandis, M.D., co-founder and co-chairman, Planetary Resources, Inc., stated, "The successful deployment of the A3R is a significant milestone for Planetary Resources as we forge a path toward prospecting resource-rich asteroids. Our team is developing the technology that will enable humanity to create an off-planet economy that will fundamentally change the way we live on Earth."
Once the A3R completes its mission, the validated and evolved technologies will be the main components of the Arkyd series of deep-space asteroid-prospecting spacecraft. The next demonstrator, the Arkyd-6 (pictured below), will be launched later this year and will test the attitude control, power, communication and avionics systems.
Planetary Resources is leveraging the increased payload capacity of the A6 to begin demonstration of core technology to measure resources on water-rich asteroids. Included in the payload is a mid-wave infrared imaging system, able to precisely measure temperature differences of the objects it observes, as well as acquire key data related to the presence of water and water-bearing minerals. The system will first test targeted areas of our own planet before being deployed to near-Earth asteroids on future missions.
Eric Anderson, co-founder and co-chairman, Planetary Resources, Inc., said, "This key technology for determining resources on asteroids can also be applied towards monitoring and managing high-value resources on our home planet. All of our work at Planetary Resources is laying the foundation to better manage and increase humanity's access to natural resources on our planet and in our Solar System."
In related news, the SPACE Act of 2015 was recently passed in the House of Representatives. As Peter explains in the video below, this recognises the rights of U.S. asteroid mining companies to declare mined asteroid resources as property and creates a process for resolving disputes. The Senate is currently reviewing a duplicate version of the House language, S. 976.
Astronomers report the discovery of a new type of planet, resembling a giant comet.
Artist's impression. Credit: University of Geneva (UNIGE)
Astronomers using NASA's Hubble Space Telescope have discovered an immense cloud of hydrogen – dubbed "The Behemoth" – which is trailing away from a planet orbiting a nearby red dwarf. This huge, comet-like feature is about 50 times the size of the star.
Located 33 light years away, Gliese 436 b is a "warm Neptune" circling just 3 million miles (4.8 million km) from its host, or about 13 times smaller than the distance between Mercury and our Sun. It takes only two days and 15.5 hours to complete one orbit. This close proximity and the extreme radiation from the parent star have been gradually stripping away the atmosphere of Gliese 436 b. It is currently losing about 1,000 tons of gas per second.
"This cloud is very spectacular, though the evaporation rate does not threaten the planet right now," explains the study's leader, David Ehrenreich from the University of Geneva in Switzerland. "But we know that in the past, the star, which is a faint red dwarf, was more active. This means that the planet evaporated faster during its first billion years of existence. Overall, we estimate that it may have lost up to 10 percent of its atmosphere."
The cloud of hydrogen forms a circular head surrounding Gliese 436 b, measuring about 1.8 million miles (3 million km) in diameter. The tail behind it stretches up to 9.3 million miles (15 million km) in length, based on the researchers' computer models.
This comet-like planet is the first of its kind to ever be recorded. This type of observation is very promising in the search for habitable planets since "hydrogen from the ocean water that evaporates on slightly hotter terrestrial planets than the Earth could be detected," as Vincent Bourrier suggests, co-author of these results.
Its discovery could also help scientists to envisage the distant future of our own planet, billions of years from now, when the Sun becomes a red giant and expands to engulf our atmosphere. It is hypothesised that the Earth would be turned into a giant comet, just like Gliese 436 b. The James Webb Space Telescope, due for launch in 2018, could provide more accurate data and fresh insights into this system.
The study was published yesterday in the journal Nature.
The New Horizons probe is now just 36 days away from its historic encounter with Pluto. Based on the little visual information gleaned so far, NASA has released these new artist's renderings of the dwarf planet and its moons. The mission team is currently looking for any indications of dust or debris that might threaten the spacecraft's flight through the Pluto system on 14th July. At such high speed, even a particle as small as a grain of rice could be fatal. They expect to complete a thorough analysis of the data and report on its results by Friday this week. No rings, new moons, or other potential hazards have been detected so far; but if any dangers are found, the team has until 4th July to divert the probe to one of three alternate routes.
The United Arab Emirates (UAE) has reaffirmed its commitment to sending a probe to Mars in 2021. More details have emerged of the planned mission, which is timed to coincide with the 50th anniversary of the UAE's formation. In this new video, from the Mohammed Bin Rashid Space Centre (MBRSC), scientists explain how the 1,500 kilogram Hope (or "al-Amal" in Arabic) spacecraft will study the Martian atmosphere and climate.
If successful, not only will it become the first Arabian mission to Mars, it will also create the first planet-wide picture of how the Martian atmosphere changes throughout the day and between seasons. This could improve our understanding of how aerosols, ozone, water ice, water vapour and other physical processes affect us here on Earth, while also being useful in planning future manned colonies. The resulting data will be shared freely with over 200 institutions worldwide. More information is available on the MBRSC website, which includes an image gallery.
Reaction Engines Ltd. – a British aerospace company – has announced that analysis undertaken by the US Air Force Research Laboratory (AFRL) has confirmed the feasibility of the Synergetic Air-Breathing Rocket Engine ('SABRE') concept.
Through its ability to "breathe" air from the atmosphere, SABRE could offer a significant reduction in propellant consumption compared to conventional rocket engines that have to carry their own oxygen, which is heavy. The weight saved by carrying less oxygen could improve launch vehicle capabilities, by greatly increasing their operational flexibility and efficiency, while lowering costs by an order of magnitude. Space tourism would become far cheaper and safer. Additionally, the SABRE concept could potentially be configured to efficiently power aircraft flying at high supersonic and hypersonic speeds.
New analysis by the US AFRL, as part of a joint research collaboration agreement, examined the thermodynamic cycle of the SABRE concept. They found no significant barrier to its theoretical viability, provided the engine component and integration challenges are met. Reaction Engines Ltd. and AFRL are now formulating plans for continued collaboration on the SABRE engine. The proposed work will include investigation of vehicle concepts based on a SABRE-derived propulsion system.
The next phase will also include physical testing of SABRE engine components, alongside exploration of the defence applications for Reaction Engines' heat exchanger technologies.
Sam Hutchison, Director of Corporate Development at Reaction Engines, commented as follows: “The confirmation by AFRL of the feasibility of the SABRE engine cycle has further validated our team’s own assessment and conviction that the SABRE engine represents a potential breakthrough in propulsion that could lead to game changing space access and high speed flight capability. We look forward to continued collaboration with AFRL”.
If all goes to plan, the first test flights of Skylon – a single-stage-to-orbit spaceplane using the SABRE engine – could occur within five years, with visits to the International Space Station during the early 2020s.