̽��ֱ�� of Cambridge - telescope

Mission to map the dark Universe sets off on space journey

sc604 — Sat, 01 Jul 2023 15:16:27 +0000

̽��ֱ��Euclid space telescope will map the 'dark Universe' by observing billions of galaxies out to 10 billion light-years, across more than a third of the sky, to gather data on how its structure has formed over its cosmic history.

Led by the European Space Agency (ESA) and a consortium of 2,000 scientists, including from the ̽��ֱ�� of Cambridge, Euclid will spend six years venturing through space with two scientific instruments: a UK-built visible imager (VIS) that will become one of the largest cameras ever sent into space, and a near-infrared spectrometer and photometer, developed in France. ̽��ֱ��mission is supported by funding from the UK Space Agency.

“Watching the launch of Euclid, I feel inspired by the years of hard work from thousands of people that go into space science missions, and the fundamental importance of discovery – how we set out to understand and explore the Universe,” said Chief Executive of the UK Space Agency, Dr Paul Bate. “ ̽��ֱ��UK Space Agency’s investment in Euclid has supported world-class science on this journey, from the development of the ground segment to the build of the crucial visible imager instrument, which will help humanity begin to uncover the mysteries of dark matter and dark energy.”

Euclid took off on board a SpaceX spacecraft from Cape Canaveral in Florida at 4.11pm (BST) on 1 July.

Cambridge’s Institute of Astronomy team has been involved in Euclid since 2010, supporting development of the astrometric calibration pipeline for the optical image data from Euclid, ensuring that the positions of the billions of sources to be imaged by Euclid can be determined to exquisite accuracy.

“Dark energy and dark matter fundamentally govern the formation and evolution of our Universe,” said Dr Nicholas Walton from the Institute of Astronomy. “ ̽��ֱ��Euclid mission will finally uncover the mysteries of how these ‘dark’ forces have shaped the cosmos that we see today, from life here on Earth, to our Sun, our Milky Way, our nearby galaxy neighbours, and the wider Universe beyond.”

̽��ֱ��Science and Technology Facilities Council (STFC) also contributed to design and development work on Euclid instrumentation and provided funding to UK astronomy teams who will analyse the data returned from the mission about the physics responsible for the observed accelerated expansion of the Universe.

“This is a fantastic example of close collaboration between scientists, engineers, technicians, and astronomers across Europe working together to tackle some of the biggest questions in science,” said Mark Thomson, Executive Chair at STFC.

UK Space Agency funding for the Euclid mission is divided between teams at ̽��ֱ�� College London, ̽��ֱ��Open ̽��ֱ��, ̽��ֱ�� of Cambridge, ̽��ֱ�� of Edinburgh, ̽��ֱ�� of Oxford, ̽��ֱ�� of Portsmouth and Durham ̽��ֱ��.

̽��ֱ��wider Euclid Consortium includes experts from 300 organisations across 13 European countries, the US, Canada and Japan.

A European mission to explore how gravity, dark energy and dark matter shaped the evolution of the Universe soared into space from Cape Canaveral on 1 July.

̽��ֱ��Euclid mission will finally uncover the mysteries of how these ‘dark’ forces have shaped the cosmos that we see today, from life here on Earth, to our Sun, our Milky Way, our nearby galaxy neighbours, and the wider Universe beyond

Nicholas Walton

ESA

Last glimpse of Euclid on Earth

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

New findings that map the universe’s cosmic growth support Einstein’s theory of gravity

sc604 — Tue, 11 Apr 2023 14:00:00 +0000

̽��ֱ��findings, from the Atacama Cosmology Telescope collaboration involving researchers from the ̽��ֱ�� of Cambridge, provide further support to Einstein’s theory of general relativity, which has been the foundation of the standard model of cosmology for more than a century. ̽��ֱ��results offer new methods to demystify dark matter, the unseen mass thought to account for 85% of the matter in the universe.

For millennia, humans have been fascinated by the mysteries of the cosmos. From ancient civilisations such as the Babylonians, Greeks, and Egyptians to modern-day astronomers, the allure of the starry sky has inspired countless quests to unravel the secrets of the universe.

And although models that explain the cosmos have existed for centuries, the field of cosmology, where scientists use quantitative methods to understand the evolution and structure of the universe, is relatively new—having only formed in the early 20th century with the development of Albert Einstein’s theory of general relativity.

Now, a set of papers submitted to ̽��ֱ��Astrophysical Journal by researchers from the Atacama Cosmology Telescope (ACT) collaboration has produced a new image that reveals the most detailed map of matter distributed across a quarter of the entire sky, reaching deep into the cosmos. It confirms Einstein’s theory about how massive structures grow and bend light, with a test that spans the entire age of the universe.

“We have mapped the invisible dark matter across the sky to the largest distances, and clearly see features of this invisible world that are hundreds of millions of light-years across,” said co-author Professor Blake Sherwin from Cambridge’s Department of Applied Mathematics and Theoretical Physics, where he leads a group of ACT researchers. “It looks just as our theories predict.”

Although dark matter makes up a large chunk of the universe and shaped its evolution, it has remained hard to detect because it doesn’t interact with light or other forms of electromagnetic radiation. As far as we know, dark matter only interacts with gravity.

To track it down, the more than 160 collaborators who have built and gathered data from the National Science Foundation’s Atacama Cosmology Telescope in the high Chilean Andes observe light emanating following the dawn of the universe’s formation, the Big Bang—when the universe was only 380,000 years old. Cosmologists often refer to this diffuse light that fills our entire universe as the “baby picture of the universe,” but formally, it is known as the cosmic microwave background radiation (CMB).

̽��ֱ��team tracks how the gravitational pull of large, heavy structures including dark matter warps the CMB on its 14-billion year journey to us, like how a magnifying glass bends light as it passes through its lens.

“We’ve made a new mass map using distortions of light left over from the Big Bang,” said Mathew Madhavacheril from the ̽��ֱ�� of Pennsylvania, lead author of one of the papers. “Remarkably, it provides measurements that show that both the ‘lumpiness’ of the universe, and the rate at which it is growing after 14 billion years of evolution, are just what you’d expect from our standard model of cosmology based on Einstein's theory of gravity.”

“Our results also provide new insights into an ongoing debate some have called ‘ ̽��ֱ��Crisis in Cosmology’,” said Sherwin. This crisis stems from recent measurements that use a different background light, one emitted from stars in galaxies rather than the CMB. These have produced results that suggest the dark matter was not lumpy enough under the standard model of cosmology and led to concerns that the model may be broken. However, the team’s latest results from ACT were able to precisely assess that the vast lumps seen in this image are the exact right size.

“When I first saw them, our measurements were in such good agreement with the underlying theory that it took me a moment to process the results,” said Cambridge PhD candidate Frank Qu, lead author of one of the new papers. “But we still don’t know what the dark matter is, so it will be interesting to see how this possible discrepancy between different measurements will be resolved.”

“ ̽��ֱ��CMB lensing data rivals more conventional surveys of the visible light from galaxies in their ability to trace the sum of what is out there,” said Suzanne Staggs from Princeton ̽��ֱ��, Director of ACT. “Together, the CMB lensing and the best optical surveys are clarifying the evolution of all the mass in the universe.”

“When we proposed this experiment in 2003, this measurement wasn’t even on our agenda; we had no idea the full extent of information that could be extracted from our telescope,” said Mark Devlin, from the ̽��ֱ�� of Pennsylvania, Deputy Director of ACT. “We owe this to the cleverness of the theorists, the many people who built new instruments to make our telescope more sensitive, and the new analysis techniques our team came up with.”

With ACT having been decommissioned in late 2022, further papers highlighting some of the other final results are slated for submission in the coming year. Observations will continue at the site with the Simons Observatory, including a new telescope due to begin in 2024 that can map the sky almost ten times faster.

̽��ֱ��pre-print articles highlighted in this release are available on act.princeton.edu and will appear on the open-access arXiv.org. They have been submitted to ̽��ֱ��Astrophysical Journal.

This work was supported by the U.S. National Science Foundation, Princeton ̽��ֱ��, the ̽��ֱ�� of Pennsylvania, and a Canada Foundation for Innovation award. Team members at the ̽��ֱ�� of Cambridge were supported by the European Research Council.

A new image reveals the most detailed map of dark matter distributed across a quarter of the entire sky, reaching deep into the cosmos.

We have mapped the invisible dark matter across the sky to the largest distances, and clearly see features of this invisible world that are hundreds of millions of light-years across

Blake Sherwin

ACT Collaboration

A new map of the dark matter made by the Atacama Cosmology Telescope. ̽��ֱ��orange regions show where there is more mass; purple where there is less.

Yes

UK-led robotic sky scanner reveals its first galactic fingerprint

sc604 — Mon, 12 Dec 2022 09:05:03 +0000

̽��ֱ��spectra provide a first glimpse of the sky from the WHT Enhanced Area Velocity Explorer (WEAVE) – a unique upgrade to the William Herschel Telescope (WHT) in La Palma on the Canary Islands.

After its integration into the WHT last year, WEAVE has now begun its on-sky commissioning phase, ready to reveal more than 12 million spectra of stars and galaxies over the next five years.

̽��ֱ��Science and Technology Facilities Council (STFC) is one of the key partners in the operation of the WHT. Data processing, analysis and archiving for WEAVE is led by astronomers from the ̽��ֱ�� of Cambridge, with support from the IAC in Spain and INAF in Italy.

Understanding the Universe through spectra

Spectroscopy is an essential element in an astronomer’s toolbox. Analysing light detected with a telescope reveals useful scientific information, such as the speed of the object observed, the atoms it is made of and its temperature.

If an image tells us what an astronomical object looks like, its spectrum tells us what it is.

First galactic spectra with WEAVE

A galactic spectrum is the combination of spectra from the millions of stars in an observed galaxy. Studying the features of a galaxy spectrum allows astronomers to understand what types of stars the galaxy contains, and the relative abundances of each type of star. This tells us about how the galaxy formed and changed over time.

First-light observations with WEAVE were carried out with the large integral-field unit (LIFU) fibre bundle, one of WEAVE's three fibre systems. ̽��ֱ��team observed the heart of the galaxy group Stephan’s Quintet, a group of five interacting galaxies.

̽��ֱ��instrument was aimed at NGC 7318a and NGC 7318b, a pair of galaxies at the centre of a major galaxy collision 280 million light-years from Earth in the constellation Pegasus.

“ ̽��ֱ��wealth of complexity revealed in this way by a single detailed observation of this pair of nearby galaxies provides insights into the interpretation of the many millions of spectra that WEAVE will obtain from galaxies in the distant Universe and provides an excellent illustration of the power and flexibility of the WEAVE facility,” said Professor Gavin Dalton from the ̽��ֱ�� of Oxford.

̽��ֱ��WEAVE LIFU (large integral-field unit) measures separate spectra for 547 different regions in and around the two galaxies, recording the colours of their light from the ultraviolet to the near-infrared.

These spectra reveal the motions of stars and gas, the chemical composition of the stars, the temperatures and densities of the gas clouds, and more. This data will help astronomers learn how galaxy collisions transform the galaxies in the group.

“Without even breaking a sweat, WEAVE has provided us with an unprecedented glimpse into the dance of this enigmatic group of galaxies,” said Dr David Murphy from Cambridge’s Institute of Astronomy, lead of spectroscopic pipeline development for WEAVE. “This exciting initial release provides a snapshot of the various ways the instrument can provide insights into the universe. Coupled with our rapid-response data-processing pipelines, WEAVE will advance cutting-edge research ranging from the complex chemical fingerprint of our galactic neighbourhood to the very structure and fabric of our universe.”

“Our advanced analysis pipeline consists of a chain of more than 20 state-of-art modules developed to analyse a wide range of astronomical targets, from newly born hot stars to quasars,” said Dr Alireza Molaeinezhad from Cambridge’s Institute of Astronomy, Lead developer of the Advanced Processing System. “Using this pipeline on the phenomenal first-light data is like wearing 3D-glasses to watch the cosmic dance of galaxies in this system.”

Eight surveys using WEAVE

In the coming five years, the ING (Isaac Newton Group of Telescopes) will assign 70% of the time available on the WHT to eight major surveys with WEAVE, selected out of those proposed by the astronomical communities of the partner countries. All these surveys require spectra of up to millions of individual stars and galaxies, a goal now obtainable thanks to WEAVE’s ability to observe almost 1000 objects at a time.

Over 500 astronomers from across Europe have organized these eight surveys, covering studies of stellar evolution, Milky Way science, galaxy evolution and cosmology. WEAVE will study galaxies near and far to learn the history of their growth, and will obtain millions of spectra of stars in the Milky Way.

“This first light event is a milestone for both the international and UK astronomy communities: WEAVE will provide spectra of millions of stars and galaxies over the next five years,” said Professor Mark Thomson, STFC Executive Chair. “After ten years in development, WEAVE will now finally offer astronomers a new eye to the sky to help them answer questions such as what is dark matter and how did stars form in distant galaxies?”

“These wonderful first light images demonstrate the power of WEAVE to unravel the intricate chemo-dynamical processes at work in this galaxy system," said Dr Nicholas Walton from the Institute of Astronomy and lead of the WEAVE data analysis system development team. " ̽��ֱ��analysis of this data, from one of the many observational modes of WEAVE, has used our state-of-the-art science pipelines. We are now ready to handle the nightly data from WEAVE as it embarks on its main science surveys."

̽��ֱ��Isaac Newton Group of Telescopes (ING) is operated on behalf of the STFC in the UK, the Nederlanse Organisatie voor Wetenschappelijk Onderzoek (NWO) in ̽��ֱ��Netherlands, and the Instituto de Astrofísica de Canarias (IAC) in Spain.

Adapted from an STFC press release.

A major telescope upgrade has peered through to the distant Universe to reveal the spectra of a pair of galaxies 280 million light years away from Earth.

Without even breaking a sweat, WEAVE has provided us with an unprecedented glimpse into the dance of this enigmatic group of galaxies

David Murphy

ING

Blue, green and red colours, according to velocities derived from the WEAVE spectra, are overlaid on a composite image of Stephan’s Quintet, featuring galaxy star light (CFH telescope), and X-ray emission of hot gas (blue vertical band, Chandra X-ray)

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Dust plumes observed being ‘pushed’ into interstellar space by intense starlight

sc604 — Wed, 12 Oct 2022 14:51:07 +0000

Astronomers have observed directly for the first time how intense light from stars can ‘push’ matter. Researchers from the universities of Cambridge and Sydney made the observation when tracking a giant plume of dust generated by the violent interactions between two massive stars.

Hubble sees new atmosphere forming on a rocky exoplanet

sc604 — Thu, 11 Mar 2021 14:00:00 +0000

̽��ֱ��planet GJ 1132 b appears to have begun life as a gaseous world with a thick blanket of atmosphere. Starting out at several times the radius of Earth, this ‘sub-Neptune’ quickly lost its primordial hydrogen and helium atmosphere, which was stripped away by the intense radiation from its hot, young star. In a short period of time, it was reduced to a bare core about the size of Earth.

To the surprise of astronomers, new observations from Hubble have uncovered a secondary atmosphere that has replaced the planet’s first atmosphere. It is rich in hydrogen, hydrogen cyanide, methane and ammonia, and also has a hydrocarbon haze. Astronomers theorise that hydrogen from the original atmosphere was absorbed into the planet’s molten magma mantle and is now being slowly released by volcanism to form a new atmosphere. This second atmosphere, which continues to leak away into space, is continually being replenished from the reservoir of hydrogen in the mantle’s magma.

“This second atmosphere comes from the surface and interior of the planet, and so it is a window onto the geology of another world,” said team member Paul Rimmer from the ̽��ֱ�� of Cambridge. “A lot more work needs to be done to properly look through it, but the discovery of this window is of great importance.”

“We first thought that these highly radiated planets would be pretty boring because we believed that they lost their atmospheres,” said team member Raissa Estrela of the Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, California, USA. “But we looked at existing observations of this planet with Hubble and realised that there is an atmosphere there.”

“How many terrestrial planets don’t begin as terrestrials? Some may start as sub-Neptunes, and they become terrestrials through a mechanism whereby light evaporates the primordial atmosphere. This process works early in a planet’s life, when the star is hotter,” said team leader Mark Swain of the Jet Propulsion Laboratory. “Then the star cools down and the planet’s just sitting there. So you’ve got this mechanism that can cook off the atmosphere in the first 100 million years, and then things settle down. And if you can regenerate the atmosphere, maybe you can keep it.”

In some ways, GJ 1132 b has various parallels to Earth, but in some ways, it is also very different. Both have similar densities, similar sizes, and similar ages, being about 4.5 billion years old. Both started with a hydrogen-dominated atmosphere, and both were hot before they cooled down. ̽��ֱ��team’s work even suggests that GJ 1132 b and Earth have similar atmospheric pressure at the surface.

However, the planets’ formation histories are profoundly different. Earth is not believed to be the surviving core of a sub-Neptune. And Earth orbits at a comfortable distance from our yellow dwarf Sun. GJ 1132 b is so close to its host red dwarf star that it completes an orbit the star once every day and a half. This extremely close proximity keeps GJ 1132 b tidally locked, showing the same face to its star at all times — just as our moon keeps one hemisphere permanently facing Earth.

“ ̽��ֱ��question is, what is keeping the mantle hot enough to remain liquid and power volcanism?” asked Swain. “This system is special because it has the opportunity for quite a lot of tidal heating.”

̽��ֱ��phenomenon of tidal heating occurs through friction, when energy from a planet’s orbit and rotation is dispersed as heat inside the planet. GJ 1132 b is in an elliptical orbit, and the tidal forces acting on it are strongest when it is closest to or farthest from its host star. At least one other planet in the host star’s system also exerts a gravitational pull on the planet. ̽��ֱ��consequences are that the planet is squeezed or stretched by this gravitational “pumping.” That tidal heating keeps the mantle liquid for a long time. A nearby example in our own Solar System is the Jovian moon, Io, which has continuous volcanism as a result of a tidal tug-of-war between Jupiter and the neighbouring Jovian moons.

̽��ֱ��team believes the crust of GJ 1132 b is extremely thin, perhaps only hundreds of feet thick. That’s much too feeble to support anything resembling volcanic mountains. Its flat terrain may also be cracked like an eggshell by tidal flexing. Hydrogen and other gases could be released through such cracks.

“This atmosphere, if it’s thin — meaning if it has a surface pressure similar to Earth — probably means you can see right down to the ground at infrared wavelengths. That means that if astronomers use the James Webb Space Telescope to observe this planet, there’s a possibility that they will see not the spectrum of the atmosphere, but rather the spectrum of the surface,” said Swain. “And if there are magma pools or volcanism going on, those areas will be hotter. That will generate more emission, and so they’ll potentially be looking at the actual geological activity — which is exciting!”

This result is significant because it gives exoplanet scientists a way to figure out something about a planet's geology from its atmosphere,” said Rimmer, who is affiliated both with Cambridge’s Cavendish Laboratory and Department of Earth Sciences. “It is also important for understanding where the rocky planets in our own Solar System — Mercury, Venus, Earth and Mars, fit into the bigger picture of comparative planetology, in terms of the availability of hydrogen versus oxygen in the atmosphere.”

Adapted from an ESA/JPL press release.

For the first time, scientists using the NASA/ESA Hubble Space Telescope have found evidence of volcanic activity reforming the atmosphere on a rocky planet around a distant star. ̽��ֱ��planet, GJ 1132 b, has a similar density, size, and age to Earth.

It is a window onto the geology of another world

Paul Rimmer

NASA, ESA, and R. Hurt (IPAC/Caltech)

Artist’s impression of the exoplanet GJ 1132 b

Yes

Journeys of discovery: Jocelyn Bell Burnell and pulsars

lw355 — Sun, 29 Nov 2020 08:00:02 +0000

"On 28 November 1967, it came again, a string of pulses one-and-a third seconds apart." This was not the work of Little Green Men. Jocelyn Bell had discovered pulsars.

Design work on ‘brain’ of world’s largest radio telescope completed

sc604 — Thu, 09 May 2019 09:47:47 +0000

̽��ֱ��SKA’s Science Data Processor (SDP) consortium has concluded its engineering design work, marking the end of five years’ work to design one of two supercomputers that will process the enormous amounts of data produced by the SKA’s telescopes.

̽��ֱ��SDP consortium, led by the ̽��ֱ�� of Cambridge, has designed the elements that will together form the ‘brain’ of the SKA. SDP is the second stage of processing for the masses of digitised astronomical signals collected by the telescope’s receivers. In total, close to 40 institutions in 11 countries took part.

̽��ֱ��UK government, through the Science and Technology Facilities Council (STFC), has committed £100m to the construction of the SKA and the SKA Headquarters, as its share as a core member of the project. ̽��ֱ��global headquarters of the SKA Organisation are located in the UK at Jodrell Bank, home to the iconic Lovell Telescope

“It’s been a real pleasure to work with such an international team of experts, from radio astronomy but also the High-Performance Computing industry,” said Maurizio Miccolis, SDP’s Project Manager for the SKA Organisation. “We’ve worked with almost every SKA country to make this happen, which goes to show how hard what we’re trying to do is.”

̽��ֱ��role of the consortium was to design the computing hardware platforms, software, and algorithms needed to process science data from the Central Signal Processor (CSP) into science data products.

“SDP is where data becomes information,” said Rosie Bolton, Data Centre Scientist for the SKA Organisation. “This is where we start making sense of the data and produce detailed astronomical images of the sky.”

To do this, SDP will need to ingest the data and move it through data reduction pipelines at staggering speeds, to then form data packages that will be copied and distributed to a global network of regional centres where it will be accessed by scientists around the world.

SDP itself will be composed of two supercomputers, one located in Cape Town, South Africa and one in Perth, Australia.

“We estimate SDP’s total compute power to be around 250 PFlops – that’s 25% faster than IBM’s Summit, the current fastest supercomputer in the world,” said Maurizio. “In total, up to 600 petabytes of data will be distributed around the world every year from SDP –enough to fill more than a million average laptops.”

Additionally, because of the sheer quantity of data flowing into SDP: some 5 Tb/s, or 100,000 times faster than the projected global average broadband speed in 2022, it will need to make decisions on its own in almost real-time about what is noise and what is worthwhile data to keep.

̽��ֱ��team also designed SDP so that it can detect and remove manmade radio frequency interference (RFI) – for example from satellites and other sources – from the data.

“By pushing what’s technologically feasible and developing new software and architecture for our HPC needs, we also create opportunities to develop applications in other fields,” said Maurizio.

High-Performance Computing plays an increasingly vital role in enabling research in fields such as weather forecasting, climate research, drug development and many others where cutting-edge modelling and simulations are essential.

Professor Paul Alexander, Consortium Lead from Cambridge’s Cavendish Laboratory said: “I’d like to thank everyone involved in the consortium for their hard work over the years. Designing this supercomputer wouldn’t have been possible without such an international collaboration behind it.”

An international group of scientists led by the ̽��ֱ�� of Cambridge has finished designing the ‘brain’ of the Square Kilometre Array (SKA), the world’s largest radio telescope. When complete, the SKA will enable astronomers to monitor the sky in unprecedented detail and survey the entire sky much faster than any system currently in existence.

Designing this supercomputer wouldn’t have been possible without such an international collaboration behind it

Paul Alexander

SKA Organisation

Artist’s impression of the full Square Kilometre Array at night

Yes

Planets similar to Jupiter are likely able to form on orbits shorter than the Earth’s

Anonymous — Fri, 15 Jul 2016 13:48:18 +0000

Warm Jupiters are large, gas-giant exoplanets—planets found around stars other than the Sun. They are comparable in size to Jupiter and Saturn in our Solar System. But unlike the Sun’s family of giant planets, Warm Jupiters orbit their parent stars at roughly the same distance that Mercury, Venus and the Earth circle the Sun. They take ten to two hundred days to complete a single orbit instead of decades. Their origin is heavily debated topic of research.

It is generally thought that Warm Jupiters cannot form on the orbits that we find them on today; they are too close to their parent stars to have accumulated enough mass, and sufficient gas. Instead, it appeared more likely that they had formed in the outer reaches of their planetary systems and had migrated inward to their current positions. However such a migratory history would also leave a trace. ̽��ֱ��large gravity of any migrating Warm Jupiter would have disturbed any neighbouring or companion planets, ejecting them from the system.

But, instead of finding “lonely”, companion-less Warm Jupiters, the team found that 11 of the 27 targets they studied have companions ranging in size from Earth-like to Neptune-like.

̽��ֱ��team’s analysis, published this week in the Astrophysical Journal, demonstrates the existence of two distinct types of warm Jupiters, each with their own formation and dynamical history.

̽��ֱ��two types include those that have smaller planetary companions and thus, likely formed near to where we find them today; and warm Jupiters without any companions indicating that they likely migrated to their current positions.

̽��ֱ��presence of many smaller sized planetary companions to warm Jupiters provides our strongest evidence that planets similar to Jupiter and Saturn can assemble on orbits shorter than the Earth’s. “And when we take into account that there is more analysis to come,” says lead-author Chelsea Huang, “the number of Warm Jupiters with smaller neighbours may be even higher. We may find that more than half have companions.”

This result came as a “surprise” according to Amaury Triaud, now a research fellow at the Institute of Astronomy, in Cambridge. “Before starting this study, we had not anticipated this remarkable result. This challenges our ideas about which conditions are sufficient for the formation of planets. It reinforces the view that planets form in richer and more diverse ways than what can be glimpsed from the sole study of the Solar system planets.”

Reference

Huang, C et al. Warm Jupiters are less lonely than Hot Jupiters: close neighbors. Astrophysical Journal; 6 July 2016; DOI:10.3847/0004-637X/825/2/98

Based on a press release prepared by the ̽��ֱ�� of Toronto.

After analyzing four years of Kepler space telescope observations, astronomers from the ̽��ֱ�� of Toronto, and of the ̽��ֱ�� of Cambridge have given us our clearest understanding yet of a class of exoplanets called “warm Jupiters”, showing that many have unexpected planetary companions.

We had not anticipated this remarkable result. This challenges our ideas about which conditions are sufficient for the formation of planets.

Amaury Triaud

Detlev Van Ravenswaay/Science Photo Library

An artist’s portrayal of a Warm Jupiter gas-giant planet (r.) in orbit around its parent star, along with smaller companion planets.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes