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(28 July 2020 – ESA) A global collaboration of telescopes including ESA’s Integral high-energy space observatory has detected a unique mix of radiation bursting from a dead star in our galaxy — something that has never been seen before in this type of star, and may solve a long-standing cosmic mystery.

The finding involves two kinds of interesting cosmic phenomena: magnetars and Fast Radio Bursts. Magnetars are stellar remnants with some of the most intense magnetic fields in the Universe. When they become ‘active’, they can produce short bursts of high-energy radiation that typically last for not even a second but are billions of times more luminous than the Sun.

Fast Radio Bursts are one of astronomy’s major unsolved mysteries. First discovered in 2007, these events pulse brightly in radio waves for just a few milliseconds before fading away, and are only rarely seen again. Their true nature remains unknown, and no such burst has ever been observed either within the Milky Way, with a known origin, or emitting any other kind of radiation beyond the radio wave domain — until now.

In late April, SGR 1935+2154, a magnetar discovered six years ago in the constellation of Vulpecula, following a substantial burst of X-rays, became active again. Soon after, astronomers spied something astonishing: this magnetar was not only radiating its usual X-rays, but radio waves, too.

Integral: gamma-ray observatory (courtesy: ESA/Medialab)

“We detected the magnetar’s burst of high-energy, or ‘hard’, X-rays using Integral on 28 April,” says Sandro Mereghetti of the National Institute for Astrophysics (INAF–IASF) in Milan, Italy, lead author of a new study of this source based on the Integral data.

“The ‘Burst Alert System’ on Integral automatically alerted observatories worldwide about the discovery in just seconds. This was hours before any other alerts were issued, enabling the scientific community to act fast and explore this source in more detail.”

Astronomers on the ground spotted a short and extremely bright burst of radio waves from the direction of SGR 1935+2154 using the CHIME radio telescope in Canada on the same day, over the same timeframe as the X-ray emission. This was independently confirmed a few hours later by the Survey for Transient Astronomical Radio Emission 2 (STARE2) in the US.

“We’ve never seen a burst of radio waves, resembling a Fast Radio Burst, from a magnetar before,” adds Sandro.

“Crucially, the IBIS imager on Integral allowed us to precisely pinpoint the origin of the burst, nailing its association with the magnetar,” says co-author Volodymyr Savchenko from the Integral Science Data Centre at the University of Geneva, Switzerland.

“Most of the other satellites involved in the collaborative study of this event weren’t able to measure its position in the sky — and this was crucial in identifying that the emission did indeed come from SGR1935+2154.”

“This is the first ever observational connection between magnetars and Fast Radio Bursts,” explains Sandro.

“It truly is a major discovery, and helps to bring the origin of these mysterious phenomena into focus.”

This connection strongly supports the idea that Fast Radio Bursts emanate from magnetars, and demonstrates that bursts from these highly magnetised objects can also be spotted at radio wavelengths. Magnetars are increasingly popular with astronomers, as they are thought to play a key role in driving a number of different transient events in the Universe, from super-luminous supernova explosions to distant and energetic gamma-ray bursts.

Launched in 2002, Integral carries a suite of four instruments able to simultaneously observe and take images of cosmic objects in gamma rays, X-rays, and visible light.

At the time of the burst, the magnetar happened to be in the 30 degree by 30 degree field of view of the IBIS instrument, leading to an automatic detection by the satellite’s Burst Alert System software package – operated by the the Integral Science Data Centre in Geneva – immediately alerting observatories worldwide. At the same time, the Spectrometer on Integral (SPI) also detected the of X-rays burst, along with another space mission, China’s Insight Hard X-ray Modulation Telescope (HXMT).

“This kind of collaborative, multi-wavelength approach and resulting discovery highlights the importance of timely, large-scale coordination of scientific research efforts,” adds ESA’s Integral project scientist Erik Kuulkers.

“By bringing together observations from the high-energy part of the spectrum all the way to radio waves, from across the globe and in space, scientists have been able to elucidate a long-standing mystery in astronomy. We’re thrilled that Integral played a key role in this.”

Publication

The paper “INTEGRAL discovery of a burst with associated radio emission from the magnetar SGR 1935+2154” by S. Mereghetti et al. is published in The Astrophysical Journal Letters.

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SwRI instruments aboard Rosetta help detect unexpected ultraviolet aurora at a comet

SwRI instruments aboard Rosetta help detect unexpected ultraviolet aurora at

(21 September 2020 – SwRI) Data from Southwest Research Institute-led instruments aboard ESA’s Rosetta spacecraft have helped reveal auroral emissions in the far ultraviolet around a comet for the first time.

At Earth, auroras are formed when charged particles from the Sun follow our planet’s magnetic field lines to the north and south poles. There, solar particles strike atoms and molecules in Earth’s atmosphere, creating shimmering curtains of colorful light in high-latitude skies. Similar phenomena have been seen at various planets and moons in our solar system and even around a distant star. SwRI’s instruments, the Alice far-ultraviolet (FUV) spectrograph and the Ion and Electron Sensor (IES), aided in detecting these novel phenomena at comet 67P/Churyumov-Gerasimenko (67P/C-G).

Data from Southwest Research Institute-led instruments aboard ESA’s Rosetta spacecraft helped reveal unique ultraviolet auroral emissions around irregularly shaped Comet 67P. Although these auroras are outside the visible spectra, other auroras have been seen at various planets and moons in our solar system and even around a distant star. (courtesy: ESA/Rosetta/NAVCAM)

“Charged particles from the Sun streaming towards the comet in the solar wind interact with the gas surrounding the comet’s icy, dusty nucleus and create the auroras,” said SwRI Vice President Dr. Jim Burch who leads IES. “The IES instrument detected the electrons that caused the aurora.”

The envelope of gas around 67P/C-G, called the “coma,” becomes excited by the solar particles and glows in ultraviolet light, an interaction detected by the Alice FUV instrument.

“Initially, we thought the ultraviolet emissions at comet 67P were phenomena known as ‘dayglow,’ a process caused by solar photons interacting with cometary gas,” said SwRI’s Dr. Joel Parker who leads the Alice spectrograph. “We were amazed to discover that the UV emissions are aurora, driven not by photons, but by electrons in the solar wind that break apart water and other molecules in the coma and have been accelerated in the comet’s nearby environment. The resulting excited atoms make this distinctive light.”

Dr. Marina Galand of Imperial College London led a team that used a physics-based model to integrate measurements made by various instruments aboard Rosetta.

“By doing this, we didn’t have to rely upon just a single dataset from one instrument,” said Galand, who is the lead author of a Nature Astronomy paper outlining this discovery. “Instead, we could draw together a large, multi-instrument dataset to get a better picture of what was going on. This enabled us to unambiguously identify how 67P/C-G’s ultraviolet atomic emissions form, and to reveal their auroral nature.”

“I’ve been studying the Earth’s auroras for five decades,” Burch said. “Finding auroras around 67P, which lacks a magnetic field, is surprising and fascinating.”

Following its rendezvous with 67P/C-G in 2014 through 2016, Rosetta has provided a wealth of data revealing how the Sun and solar wind interact with comets. In addition to discovering these cometary auroras, the spacecraft was the first to orbit a comet’s nucleus, the first to fly alongside a comet as it travelled into the inner Solar System and the first to send a lander to a comet’s surface.

Additional instruments contributing to this research were Rosetta’s Langmuir Probe (LAP), the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA), the Microwave Instrument for the Rosetta Orbiter (MIRO) and the Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS).

Rosetta is an ESA mission with contributions from its member states and NASA. Rosetta’s Philae lander is provided by a consortium led by DLR, MPS, CNES and ASI. Airbus Defense and Space built the Rosetta spacecraft. NASA’s Jet Propulsion Laboratory (JPL) manages the U.S. contribution of the Rosetta mission for NASA’s Science Mission Directorate in Washington, under a contract with the California Institute of Technology (Caltech). JPL also built the Microwave Instrument for the Rosetta Orbiter and hosts its principal investigator, Dr. Mark Hofstadter. SwRI (San Antonio and Boulder, Colorado) developed the Rosetta orbiter’s Ion and Electron Sensor and Alice instrument and hosts their principal investigators.

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Series C funding for ICEYE to continue conquering boundaries in radar satellite imaging

Series C funding for ICEYE to continue conquering boundaries in

(22 September 2020 – ICEYE) ICEYE today announced the closing of a larger than planned $87M Series C funding, led by return investor True Ventures, with a significant additional investment by OTB Ventures.

ICEYE has so far successfully launched 5 satellite missions, starting with the first ever small SAR satellite launched in January 2018. The company is launching 4 additional SAR satellites this year and is on course to launch at least an additional 8 in 2021. This will grow the existing operational constellation into a capability that is unique in the World. To date, ICEYE has raised a total of $152M in financing.

An artist’s depiction of two ICEYE SAR satellites in orbit. (courtesy: ICEYE)

“ICEYE is enabling others to solve immeasurably difficult problems that affect the lives of millions of people around the world. Our team has built a reputation of delivering results to our customers with unmatched timelines and quality of service. We are proud of that reputation, and we intend to maintain it,” said Rafal Modrzewski, CEO and Co-founder of ICEYE. “This round of investment ensures our SAR satellite constellation will reach a size of at least 12 satellites in 2021, guaranteeing 4 times a day revisit rate globally.”

ICEYE designs, manufactures and operates its SAR satellites in-house, with manufacturing timelines brought down to months for its spacecraft. Since the successful January 2018 launch of the first ICEYE SAR satellite, the company has delivered SAR imaging services and new capabilities to global customers. These years of operation have included many world-first achievements for small SAR satellites, such as 0.25 meter resolution data and SAR video. Recently, ICEYE has demonstrated record time data deliveries of 5 minutes from the start of data downlink to having processed images available on customer systems.

ICEYE intends to use this financing round to continue accelerating the growth of its SAR satellite constellation with more spacecraft, increasing data availability for all continents through 24/7 customer operations, continuing the development of ground-breaking radar imaging capabilities, and for establishing spacecraft manufacturing in the US. The financing round is significantly larger than originally planned, which is especially noteworthy during the economically turbulent year of 2020. It is a powerful sign of trust from the financial community that ICEYE’s business and operational model works, and that the organization is accelerating towards further global impact.

Given the unprecedented frequency and scale of climate driven changes in the weather, crop patterns, fires, urban living and human activities, there is a critical immediate need for real-time information and data access on a global scale. This access can be used for saving lives during humanitarian and disaster response situations, and for economic decision making during moments of crisis.

ICEYE has provided commercial radar satellite imaging worldwide for several years, enabling ICEYE’s customers to respond to oil spills, hurricanes, deforestation and many more use cases. Along with these active customer imaging operations, the ICEYE SAR satellite constellation has seen an unprecedented development cycle of new imaging capabilities and new spacecraft generations.

Adam Niewiński, co-founder and Managing Partner of OTB Ventures, said: “We are pleased to be a cornerstone investor in the latest round of venture funding for ICEYE. We are thrilled to be part of the evolving ecosystem where even the sky is no longer the limit.”

ICEYE’s Series C includes participation from return investors True Ventures, OTB Ventures, Finnish Industry Investment (Tesi), Draper Esprit, DNX Ventures, Draper Associates, Seraphim Capital, Promus Ventures and Space Angels. The funding round is joined by New Space Capital and Luxembourg Future Fund. The European Investment Fund (EIF) participated both as advisor to Luxembourg Future Fund and as investor through the InnovFin For Equity (IFE) programme, which is backed by the European Commission. Further, a significant portion of Tesi’s investment is supported by the European Investment Bank (EIB) under the European Fund for Strategic Investments (EFSI), the central pillar of the Investment Plan for Europe of the Juncker Commission. Coinciding with ICEYE’s Series C funding, OTB Ventures today announced the launch of a dedicated investment vehicle to support Europe’s leading space technologies – OTB Space Program I – backed by the European Investment Fund and the European Commission through the InnovFin for Equity programme.

About ICEYE

ICEYE is building and operating its own commercial constellation of radar imaging satellites, with SAR data available to global customers since 2018. With the company’s unique satellite constellation capabilities, ICEYE empowers others to make better decisions in governmental and commercial industries. The company is tackling a tremendous global need for timely and reliable information, with world-first aerospace capabilities and a New Space approach. ICEYE’s radar satellite imaging service, designed to deliver very frequent coverage, both day and night, helps clients resolve challenges in sectors such as maritime, disaster management, insurance, and finance.

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Meteorites from Vesta found on asteroid Bennu

Meteorites from Vesta found on asteroid Bennu

(21 September 2020 – NASA Goddard) It appears some pieces of asteroid Vesta ended up on asteroid Bennu, according to observations from NASA’s OSIRIS-REx spacecraft.

The new result sheds light on the intricate orbital dance of asteroids and on the violent origin of Bennu, which is a “rubble pile” asteroid that coalesced from the fragments of a massive collision.

“We found six boulders ranging in size from 5 to 14 feet (about 1.5 to 4.3 meters) scattered across Bennu’s southern hemisphere and near the equator,” said Daniella DellaGiustina of the Lunar & Planetary Laboratory, University of Arizona, Tucson. “These boulders are much brighter than the rest of Bennu and match material from Vesta.”

During spring 2019, NASA’s OSIRIS-REx spacecraft captured these images, which show fragments of asteroid Vesta present on asteroid Bennu’s surface. The bright boulders (circled in the images) are pyroxene-rich material from Vesta. Some bright material appear to be individual rocks (left) while others appear to be clasts within larger boulders (right). (courtesy: NASA/Goddard/University of Arizona)

“Our leading hypothesis is that Bennu inherited this material from its parent asteroid after a vestoid (a fragment from Vesta) struck the parent,” said Hannah Kaplan of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Then, when the parent asteroid was catastrophically disrupted, a portion of its debris accumulated under its own gravity into Bennu, including some of the pyroxene from Vesta.”

DellaGiustina and Kaplan are primary authors of a paper on this research appearing in Nature Astronomy September 21.

The unusual boulders on Bennu first caught the team’s eye in images from the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) Camera Suite (OCAMS). They appeared extremely bright, with some almost ten times brighter than their surroundings. They analyzed the light from the boulders using the OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) instrument to get clues to their composition. A spectrometer separates light into its component colors. Since elements and compounds have distinct, signature patterns of bright and dark across a range of colors, they can be identified using a spectrometer. The signature from the boulders was characteristic of the mineral pyroxene, similar to what is seen on Vesta and the vestoids, smaller asteroids that are fragments blasted from Vesta when it sustained significant asteroid impacts.

Of course it’s possible that the boulders actually formed on Bennu’s parent asteroid, but the team thinks this is unlikely based on how pyroxene typically forms. The mineral typically forms when rocky material melts at high-temperature. However, most of Bennu is composed of rocks containing water-bearing minerals, so it (and its parent) couldn’t have experienced very high temperatures. Next, the team considered localized heating, perhaps from an impact. An impact needed to melt enough material to create large pyroxene boulders would be so significant that it would have destroyed Bennu’s parent-body. So, the team ruled out these scenarios, and instead considered other pyroxene-rich asteroids that might have implanted this material to Bennu or its parent.

Observations reveal it’s not unusual for an asteroid to have material from another asteroid splashed across its surface. Examples include dark material on crater walls seen by the Dawn spacecraft at Vesta, a black boulder seen by the Hayabusa spacecraft on Itokawa, and very recently, material from S-type asteroids observed by Hayabusa2 at Ryugu. This indicates many asteroids are participating in a complex orbital dance that sometimes results in cosmic mashups.

As asteroids move through the solar system, their orbits can be altered in many ways, including the pull of gravity from planets and other objects, meteoroid impacts, and even the slight pressure from sunlight. The new result helps pin down the complex journey Bennu and other asteroids have traced through the solar system.

Based on its orbit, several studies indicate Bennu was delivered from the inner region of the Main Asteroid Belt via a well-known gravitational pathway that can take objects from the inner Main Belt to near-Earth orbits. There are two inner Main Belt asteroid families (Polana and Eulalia) that look like Bennu: dark and rich in carbon, making them likely candidates for Bennu’s parent. Likewise, the formation of the vestoids is tied to the formation of the Veneneia and Rheasilvia impact basins on Vesta, at roughly about two billion years ago and approximately one billion years ago, respectively.

“Future studies of asteroid families, as well as the origin of Bennu, must reconcile the presence of Vesta-like material as well as the apparent lack of other asteroid types. We look forward to the returned sample, which hopefully contains pieces of these intriguing rock types,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson. “This constraint is even more compelling given the finding of S-type material on asteroid Ryugu. This difference shows the value in studying multiple asteroids across the solar system.”

The spacecraft is going to make its first attempt to sample Bennu in October and return it to Earth in 2023 for detailed analysis. The mission team closely examined four potential sample sites on Bennu to determine their safety and science value before making a final selection in December 2019. DellaGiustina and Kaplan’s team thinks they might find smaller pieces of Vesta in images from these close-up studies.

The research was funded by the NASA New Frontiers Program. The primary authors acknowledge significant collaboration with the French space agency CNES and Japan Society for the Promotion of Science Core-to-core Program on this paper. NASA’s Goddard Space Flight Center in Greenbelt, Maryland provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s science observation planning and data processing. The late Michael Drake of the University of Arizona pioneered the study of vestoid meteorites and was the first principal investigator for OSIRIS-REx. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. NASA is exploring our Solar System and beyond, uncovering worlds, stars, and cosmic mysteries near and far with our powerful fleet of space and ground-based missions.

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