ESO Instrument Finds Closest Black Hole to Earth

ESO - European Southern Observatory logo.

6 May 2020

Invisible object has two companion stars visible to the naked eye

Artist’s impression of the triple system with the closest black hole

A team of astronomers from the European Southern Observatory (ESO) and other institutes has discovered a black hole lying just 1000 light-years from Earth. The black hole is closer to our Solar System than any other found to date and forms part of a triple system that can be seen with the naked eye. The team found evidence for the invisible object by tracking its two companion stars using the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. They say this system could just be the tip of the iceberg, as many more similar black holes could be found in the future.

"We were totally surprised when we realised that this is the first stellar system with a black hole that can be seen with the unaided eye,” says Petr Hadrava, Emeritus Scientist at the Academy of Sciences of the Czech Republic in Prague and co-author of the research. Located in the constellation of Telescopium, the system is so close to us that its stars can be viewed from the southern hemisphere on a dark, clear night without binoculars or a telescope. “This system contains the nearest black hole to Earth that we know of,” says ESO scientist Thomas Rivinius, who led the study published today in Astronomy & Astrophysics.

Location of the HR 6819 in the constellation of Telescopium

The team originally observed the system, called HR 6819, as part of a study of double-star systems. However, as they analysed their observations, they were stunned when they revealed a third, previously undiscovered body in HR 6819: a black hole. The observations with the FEROS spectrograph on the MPG/ESO 2.2-metre telescope at La Silla showed that one of the two visible stars orbits an unseen object every 40 days, while the second star is at a large distance from this inner pair.

Dietrich Baade, Emeritus Astronomer at ESO in Garching and co-author of the study, says: “The observations needed to determine the period of 40 days had to be spread over several months. This was only possible thanks to ESO’s pioneering service-observing scheme under which observations are made by ESO staff on behalf of the scientists needing them.”

Wide-field view of the region of the sky where HR 6819 is located

The hidden black hole in HR 6819 is one of the very first stellar-mass black holes found that do not interact violently with their environment and, therefore, appear truly black. But the team could spot its presence and calculate its mass by studying the orbit of the star in the inner pair. “An invisible object with a mass at least 4 times that of the Sun can only be a black hole,” concludes Rivinius, who is based in Chile.

Astronomers have spotted only a couple of dozen black holes in our galaxy to date, nearly all of which strongly interact with their environment and make their presence known by releasing powerful X-rays in this interaction. But scientists estimate that, over the Milky Way’s lifetime, many more stars collapsed into black holes as they ended their lives. The discovery of a silent, invisible black hole in HR 6819 provides clues about where the many hidden black holes in the Milky Way might be. “There must be hundreds of millions of black holes out there, but we know about only very few. Knowing what to look for should put us in a better position to find them,” says Rivinius. Baade adds that finding a black hole in a triple system so close by indicates that we are seeing just “the tip of an exciting iceberg.”

Artist’s animation of the triple system with the closest black hole

Already, astronomers believe their discovery could shine some light on a second system. “We realised that another system, called LB-1, may also be such a triple, though we'd need more observations to say for sure,” says Marianne Heida, a postdoctoral fellow at ESO and co-author of the paper. "LB-1 is a bit further away from Earth but still pretty close in astronomical terms, so that means that probably many more of these systems exist. By finding and studying them we can learn a lot about the formation and evolution of those rare stars that begin their lives with more than about 8 times the mass of the Sun and end them in a supernova explosion that leaves behind a black hole."

The discoveries of these triple systems with an inner pair and a distant star could also provide clues about the violent cosmic mergers that release gravitational waves powerful enough to be detected on Earth. Some astronomers believe that the mergers can happen in systems with a similar configuration to HR 6819 or LB-1, but where the inner pair is made up of two black holes or of a black hole and a neutron star. The distant outer object can gravitationally impact the inner pair in such a way that it triggers a merger and the release of gravitational waves. Although HR 6819 and LB-1 have only one black hole and no neutron stars, these systems could help scientists understand how stellar collisions can happen in triple star systems.

Zooming into HR 6819

More information:

This research was presented in the paper “A naked-eye triple system with a nonaccreting black hole in the inner binary”, published today in Astronomy & Astrophysics (doi: 10.1051/0004-6361/202038020).

The team is composed of Th. Rivinius (European Southern Observatory, Santiago, Chile), D. Baade (European Southern Observatory, Garching, Germany [ESO Germany]), P. Hadrava (Astronomical Institute, Academy of Science of the Czech Republic, Prague, Czech Republic), M. Heida (ESO Germany), and R. Klement (The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, USA).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.

Links:

ESOcast 220 Light: Closest Black Hole to Earth Found:
https://www.eso.org/public/videos/eso2007a/

Research paper: https://www.eso.org/public/archives/releases/sciencepapers/eso2007/eso2007a.pdf

Photos of the MPG/ESO 2.2-metre telescope: https://www.eso.org/public/images/archive/search/?adv=&subject_name=mpg

Photos of ESO’s La Silla Observatory: https://www.eso.org/public/images/archive/category/lasilla/

FEROS: https://www.eso.org/public/teles-instr/lasilla/mpg22/feros/

MPG/ESO 2.2-metre telescope: https://www.eso.org/public/teles-instr/lasilla/mpg22/

Images, Text, Credits: ESO/L. Calçada/IAU and Sky & Telescope/Digitized Sky Survey 2. Acknowledgement: Davide De Martin/Videos: ESO/L. Calçada/Digitized Sky Survey 2, N. Risinger (skysurvey.org). Music: Astral Electronic/ESO/Bárbara Ferreira/Marianne Heida/Thomas Rivinius/Dietrich Baade/Academy of Sciences of the Czech Republic/Petr Hadrava.

Best regards, Orbiter.ch

Shedding light on the ocean’s living carbon

ESA - Sentinel 2 Mission logo.

6 May 2020

Global annual primary production

Phytoplankton play a crucial role in ocean biology and climate. Understanding the natural processes that influence phytoplankton primary production, and how they are changing as the planet warms, is vital. A new study, using data from the European Space Agency’s Climate Change Initiative, has produced a 20-year time-series of global primary production in the oceans – shedding new light on the ocean’s living carbon pump.

Phytoplankton, microscopic, free-floating plants in aquatic systems, play an important role in the global carbon cycle by absorbing carbon dioxide on a scale equivalent to that of terrestrial plants. Primary production is an ecologic term used to describe the synthesis of organic material from carbon dioxide and water, in the presence of sunlight, through photosynthesis.

Baltic blooms

Even small variations in primary productivity can affect carbon dioxide concentrations, as well as influencing biodiversity and fisheries.

As ocean surfaces warm in response to increasing atmospheric greenhouse gases, phytoplankton productivity will need to be monitored both consistently and systematically. Although in situ measurements are necessary in studying productivity, satellite data are fundamental to providing a global view of phytoplankton and their role in, and response to, climate change.

In a recent paper published in Remote Sensing, scientists used data from the Ocean Colour Climate Change Initiative to study the long-term patterns of primary production and its interannual variability. Combining long-term satellite data with in situ measurements, they assessed global annual primary productivity from 1998-2018.

Changes in primary production varied location to location, season to season and year after year. They found that global annual primary production varied around 38 to 42 gigatonnes of carbon per year. They also observed several regional differences, with high production in coastal areas and low production in the open oceans.

Global monthly primary productivity

The paper also highlighted that phytoplankton productivity levels increase and decrease coinciding with major Earth system processes – such as El Niño, Indian Ocean Dipole and North Atlantic Oscillation.

Gemma Kulk, from Plymouth Marine Laboratory and the lead author of the paper, comments “Everyone understands why the rainforests and trees are important – they are the lungs of the Earth, taking up carbon dioxide from the atmosphere. What is overlooked is that the oceans are of equal importance – every second breath you take comes from the oceans.”

Being able to observe and quantify primary production over long-time scales will help the scientific and modelling communities to determine the effect of climate variability on these processes, as well as to identify any residual trend that signals a shift in climate.

Co-author, Shubha Sathyendranath, from Plymouth Marine Laboratory and science leader of the Ocean Colour CCI project, adds, “Although the data records span 20 years, it is important to wait at least 30 years to be able to identify any clear climate trend with sufficient confidence.

Sentinel 2

“It is critical that the ocean colour dataset as part of the Climate Change Initiative be extended and maintained on a regular basis, so that we have an empirical record of the response of ocean biota to changes in climate. From this, we can develop reliable models, so we can accurately predict change in order to adapt to the impacts of a changing world.”

The work presented here is also a contribution to ESA’s BICEP (Biological Pump and Carbon Exchange Processes) Project.

ESA’s Climate Change Initiative is a research and development programme that merges and calibrates measurements from multiple satellite missions to generate a global time-series looking at 21 key components of the climate system. Spanning decades, these long-term data records enable scientists to identify climate trends, develop and test Earth system models that predict future change and inform decision-makers to mitigate and adapt to the impacts.

Related links:

ESA’s BICEP: https://eo4society.esa.int/projects/bicep/

ESA’s Climate Change Initiative: http://cci.esa.int/

Ocean Colour Climate Change Initiative: https://esa-oceancolour-cci.org/

Remote Sensing paper: https://www.mdpi.com/2072-4292/12/5/826

Observing the Earth: http://www.esa.int/Applications/Observing_the_Earth

Space for our climate: http://www.esa.int/Applications/Observing_the_Earth/Space_for_our_climate

Copernicus Sentinel-2: https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-2

Images, Video, Animation, Text, Credits: ESA/Ocean Colour CCI, Plymouth Marine Laboratory/ESA/Contains modified Copernicus Sentinel data (2019), processed by ESA, CC BY-SA 3.0 IGO.

Greetings, Orbiter.ch

Station Trio Works Spacesuits, Science as SpaceX Readies Crew Launch

ISS - Expedition 63 Mission patch.

May 5, 2020

Spacesuits, photo inspections and pilot studies kept the Expedition 63 crew busy aboard the International Space Station today. Meanwhile, the Commercial Crew Program is getting ready to launch its first crewed mission.

Commander Chris Cassidy of NASA spent most of Tuesday inside the Quest airlock where spacewalks in U.S. spacesuits are staged. The veteran space visitor serviced the spacesuits today replacing components and cleaning cooling loops. NASA is planning a series of spacewalks later this year to upgrade power and science systems on the orbiting lab.

Image above: The three-member Expedition 63 crew aboard the International Space Station with (from left) NASA astronaut and Commander Chris Cassidy and Roscosmos cosmonauts and Flight Engineers Anatoly Ivanishin and Ivan Vagner. Image Credit: NASA.

Flight Engineer Anatoly Ivanishin of Roscosmos, a veteran of two previous station missions, spent his morning photographing the interior condition of the Zarya and Pirs modules. Russian mission controllers will inspect the photos to determine areas necessary for repair as well locations for the installation of future science experiments.

First-time space station resident Ivan Vagner began his day exploring ways crews might pilot spacecraft and robotic rovers on future planetary missions. In the afternoon, the Roscosmos cosmonaut moved on and serviced a variety of communications and life support gear.

International Space Station (ISS). Animation Credit: NASA

Back on Earth, the SpaceX Crew Dragon spacecraft is being processed at the Cape Canaveral Air Force Station in Florida. NASA astronauts Bob Behnken and Doug Hurley will be the first crew since 2011 to launch aboard an American spacecraft.

The duo will be inside the Crew Dragon atop the Falcon 9 rocket when it lifts off May 27 for a 19-hour trip to the space station. The experienced NASA astronauts will join the Expedition 63 crew for several weeks to ramp up science activities aboard the orbiting lab.

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

Commercial Crew Program: https://www.nasa.gov/commercialcrew

Zarya module: https://www.nasa.gov/mission_pages/station/structure/elements/zarya-cargo-module

Pirs modules: https://www.nasa.gov/mission_pages/station/structure/elements/pirs-docking-compartment

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

The Crab Nebula: Observations Through Time

NASA Goddard Space Flight Center logo.

May 5, 2020

This 2018 composite of the Crab Nebula was made with data from the Chandra X-Ray Observatory (blue and white), Hubble Space Telescope (purple), and Spitzer Space Telescope (pink). The star that exploded to create the Crab Nebula was first seen from Earth in 1054 A.D.

Chandra X-ray Observatory

Since its launch in 1999, Chandra has frequently observed the nebula and x-ray observations have helped astronomers better understand this spectacular object. The Crab Nebula was one of the first objects that Chandra examined with its sharp X-ray vision, and it has been a frequent target of the telescope ever since.

Hubble Space Telescope (HST)

There are many reasons that the Crab Nebula is such a well-studied object: it is one of a handful of cases where there is strong historical evidence for when the star exploded. Having this definitive timeline helps astronomers understand the details of the explosion and its aftermath.

Spitzer Space Telescope

In the case of the Crab, observers in several countries reported the appearance of a "new star" in 1054 A.D. in the direction of the constellation Taurus. Much has been learned about the Crab in the centuries since then. Today, astronomers know that the Crab Nebula is powered by a quickly spinning, highly magnetized neutron star called a pulsar, which was formed when a massive star ran out of its nuclear fuel and collapsed. The combination of rapid rotation and a strong magnetic field in the Crab generates an intense electromagnetic field that creates jets of matter and anti-matter moving away from both the north and south poles of the pulsar, and an intense wind flowing out in the equatorial direction.

Related links:

Chandra X-Ray Observatory: https://www.nasa.gov/mission_pages/chandra/main/index.html

Hubble Space Telescope: https://www.nasa.gov/mission_pages/hubble/main/index.html

Spitzer Space Telescope: https://www.nasa.gov/mission_pages/spitzer/main/index.html

Image, Animations, Text, Credits: X-ray: NASA/Yvette Smith/CXC/SAO; Optical: NASA/STScI; Infrared: NASA-JPL-Caltech.

Greetings, Orbiter.ch

Traces of tectonic activity on the Moon

NASA - Lunar Reconnaissance Orbiter (LRO) patch.

May 5, 2020

Bernese (University of Bern, Switzerland) and American researchers observed on the visible face of the Moon mountain ridges emitting a lot of heat.

Bernese and American researchers have highlighted traces of tectonic activity which would be the consequence of a gigantic impact which occurred 4.3 billion years ago.

The Moon is not a dead star as one might suppose. Bernese and American researchers have highlighted traces of recent tectonic activity which would be the consequence of a gigantic impact which occurred 4.3 billion years ago.

A doctoral student at the University of Bern, Adomas Valantinas carried out this work during a stay at Brown University (USA), using in particular data from NASA's Lunar Reconnaissance Orbiter (LRO) probe.

The researcher observed on the visible face of the Moon mountain ridges with portions of basalt rocks freshly exposed. These rocky areas release more heat during the lunar night than the surrounding dusty surface, so that they can be detected by the Diviner instrument on board the LRO probe which measures the temperature on the surface of the Moon.

Lunar Reconnaissance Orbiter (LRO)

Diviner's nocturnal readings revealed more than 500 spots of this type. With Peter Schultz of Brown University, Adomas Valantinas mapped these mountain ridges and found an almost perfect correlation with old cracks in the lunar crust discovered by NASA's GRAIL mission in 2014.

Magma channels

These cracks became channels in which magma flowed which formed deep grooves. In their study published in the journal Geology, the researchers suggest that the mountain ridges overlooking these gorges are always in an upward movement, which explains the recently exposed rocks.

Magma channels

According to them, it is possible that the phenomenon is still in progress, because on the Moon, everything is quickly covered with a dust called regolith resulting from the impacts of meteorites. According to Professor Schultz, quoted Tuesday in a press release from the University of Bern, these movements are the consequence of a gigantic impact on the hidden face of the Moon 4.3 billion years ago.

"When we return to the Moon, these places with bare boulders will be of great importance, samples will be able to give us a lot of new information," concludes Adomas Valantinas.

Related links:

University of Bern: https://www.unibe.ch/index_eng.html

NASA Lunar Reconnaissance Orbiter (LRO): https://www.nasa.gov/mission_pages/LRO/main/index.html

Images, Animation, Text, Credits: ATS/NASA/LRO/University of Bern/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

China launched a rocket with a spaceship

CASC - China Aerospace Science and Technology Corporation logo.

May 5, 2020

First launches of Long March-5B carrying China’s new-generation crewed spacecraft (CMS)

The Long March 5B rocket took off from Wenchang base. Its mission is crucial to prepare the sending of astronauts to the Moon and for its future space station.

China successfully launched a new spacecraft on Tuesday, the state agency New China announced, a crucial mission to prepare the dispatch of astronauts to its future large space station.

Long March-5B launch

Video above: The first Long March-5B launch vehicle was launched from the Wenchang Space Launch Center, Wenchang, Hainan Province, China, on 5 May 2020, at 10:00 UTC (18:00 local time). The rocket launched China’s new-generation crewed spacecraft (CMS) on a test mission. CMS is designed to be reusable and it can carry both astronauts and cargo.

The craft was propelled from the base of Wenchang on the island of Hainan (south) using a Long-March rocket 5B, of which it was the inaugural flight, reported new China. For safety, no one had taken place on board the ship because of its experimental nature.

Long March-5B launch

Its main medium-term objectives: to send astronauts to the future space station and to make manned flights to the Moon.

China has already launched since 1999 several "Shenzhou" vessels, built on the model of the famous "Soyuz" Soviets, then Russians. The new ship launched on Tuesday is said to be safer. It will be faster, more heat resistant, longer (8.8 meters) and heavier (21.6 tonnes). The spacecraft should also be able to carry more astronauts (six instead of three) and be partially reusable.

The first Long March-5B prepares for launch

Video above: The first Long March-5B launch vehicle arrived at the Wenchang Space Launch Center, Wenchang, Hainan Province, China, and is being prepared to launch China’s new crewed spacecraft in April. Long March-5B is being developed based on the Long March-5 rocket and will mainly be used for launching different modules of China’s next space station.

These characteristics open up new horizons for the Chinese manned space program. The spacecraft is thus supposed to be able to carry out more distant missions in space (to the Moon for example, or even even further), journeys which require greater speed and better protection against extreme temperatures.

 China’s new-generation crewed spacecraft (CMS) integration

The future Chinese space station (CSS), called Tiangong in Mandarin (“Celestial Palace”), will consist of three parts: a main module almost 17 meters long (place of life and work) and two additional modules (for scientific experiments ). Its assembly in space should begin this year thanks to this new Longue-Marche 5B rocket (the most powerful in the country) and will be completed in 2022.

China is investing billions of euros in its space program. It places numerous satellites in orbit, on its own account or for other countries.

 China’s new-generation crewed spacecraft (CMS)

In early 2019, it became the first nation in the world to land a probe on the far side of the Moon. In 2020, it should launch a probe to Mars. She also hopes to send a manned mission to the moon within ten years.

Related links:

China National Space Administration (CNSA): http://www.cnsa.gov.cn/english/index.html

For more information about China Aerospace Science and Technology Corporation (CASC): http://english.spacechina.com/n16421/index.html

Images, Videos, Text, Credits: ATS/CASC/China National Space Administration (CNSA)/China Central Television (CCTV)/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Cygnus Readied for Departure, Crew Trains for Medical Emergency

ISS - Expedition 63 Mission patch.

May 4, 2020

A U.S. cargo craft is one week away from completing its mission at the International Space Station. Meanwhile, the three-member Expedition 63 crew focused its attention today on emergency training and orbital maintenance.

On Monday May 11, the Cygnus space freighter from Northrop Grumman will complete its mission attached to the station’s Unity module. Cygnus will serve a dual purpose after its departure as it takes out the trash and deploys a set of CubeSats for a variety of space research.

Image above: Four spaceships are attached at the space station including the U.S. Northrop Grumman Cygnus cargo craft and Russia’s Progress 74 and 75 resupply ships and Soyuz MS-16 crew ship. Image Credit: NASA.

Commander Chris Cassidy is setting up a small satellite deployer, called the SlingShot, that will be installed on the hatch of Cygnus before its departure. The tiny satellites will test space communication technologies and advanced GPS mapping techniques.

Cassidy then joined Roscosmos Flight Engineers Anatoly Ivanishin and Ivan Vagner for an emergency drill after lunchtime. The trio practiced CPR techniques necessary in microgravity. The crewmates also reviewed medical hardware, communication and coordination in the event of a medical emergency aboard the orbiting lab.

International Space Station (ISS). Animation Credit: NASA

Ivanishin started Monday morning photographing the interior of the station’s Russian segment to document spaces that could support new research gear and areas that may require repairs. Vagner explored ways to prevent science experiments or degraded station hardware from potentially contaminating the cabin atmosphere.

Related links:

Expedition 63: https://www.nasa.gov/mission_pages/station/expeditions/expedition63/index.html

Unity module: https://www.nasa.gov/mission_pages/station/structure/elements/unity

SlingShot: https://www.nasa.gov/mission_pages/station/research/news/slingshot-small-satellite-deployment-test

Cabin atmosphere: https://www.energia.ru/en/iss/researches/develop/23.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch