ESA
NASA Selects Missions to Study Our Sun, Its Effects on Space Weather
Grey Hautaluoma / Karen Fox
NASA Headquarters, Washington
grey.hautaluoma-1@nasa.gov / karen.c.fox@nasa.gov

NASA has selected two new missions to advance our understanding of the Sun and its dynamic effects on space. One of the selected missions will study how the Sun drives particles and energy into the solar system and a second will study Earth’s response.
The Sun generates a vast outpouring of solar particles known as the solar wind, which can create a dynamic system of radiation in space called space weather. Near Earth, where such particles interact with our planet’s magnetic field, the space weather system can lead to profound impacts on human interests, such as astronauts’ safety, radio communications, GPS signals, and utility grids on the ground. The more we understand what drives space weather and its interaction with the Earth and lunar systems, the more we can mitigate its effects – including safeguarding astronauts and technology crucial to NASA’s Artemis program to the Moon.
The Many Faces of Rosetta’s Comet 67P
Markus Bauer
European Space Agency, Noordwijk, Netherlands
M. Ramy El-Maarry
University of Colorado
Matt Taylor
ESA Rosetta project scientist

NOTE: Make sure you check 0ut the accompanying Space Photo Exploration page for Comet 67P/Churyumov-Gerasimenko
Images returned from the European Space Agency’s Rosetta mission indicate that during its most recent trip through the inner solar system, the surface of comet 67P/Churyumov-Gerasimenko was a very active place – full of growing fractures, collapsing cliffs and massive rolling boulders. Moving material buried some features on the comet’s surface while exhuming others. A study on 67P’s changing surface was released Tuesday, March 21, in the journal Science.
“As comets approach the sun, they go into overdrive and exhibit spectacular changes on their surface,” said Ramy El-Maarry, study leader and a member of the U.S. Rosetta science team from the University of Colorado, Boulder. “This is something we were not able to really appreciate before the Rosetta mission, which gave us the chance to look at a comet in ultra-high resolution for more than two years.”
Dark Matter Less Influential in Galaxies in Early Universe
Reinhard Genzel
Director, Max-Planck-Institut für extraterrestrische Physik
Garching bei München, Germany
March 15, 2017

VLT observations of distant galaxies suggest they were dominated by normal matter
We see normal matter as brightly shining stars, glowing gas and clouds of dust. But the more elusive dark matter does not emit, absorb or reflect light and can only be observed via its gravitational effects. The presence of dark matter can explain why the outer parts of nearby spiral galaxies rotate more quickly than would be expected if only the normal matter that we can see directly were present [1].
Now, an international team of astronomers led by Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany have used the KMOS and SINFONI instruments at ESO’s Very Large Telescope in Chile [2] to measure the rotation of six massive, star-forming galaxies in the distant Universe, at the peak of galaxy formation 10 billion years ago.
What they found was intriguing: unlike spiral galaxies in the modern Universe, the outer regions of these distant galaxies seem to be rotating more slowly than regions closer to the core — suggesting there is less dark matter present than expected [3].
(ESO) ALMA Starts Observing the Sun
Roman Brajsa
Hvar Observatory, University of Zagreb
Croatia
Ivica Skokic
Astronomical Institute of the Czech Academy of Sciences
Ondrejov, Czech Republic

Astronomers have harnessed the Atacama Large Millimeter/submillimeter Array (ALMA)‘s capabilities to image the millimetre-wavelength light emitted by the Sun’s chromosphere — the region that lies just above the photosphere, which forms the visible surface of the Sun. The solar campaign team, an international group of astronomers with members from Europe, North America and East Asia [1], produced the images as a demonstration of ALMA’s ability to study solar activity at longer wavelengths of light than are typically available to solar observatories on Earth.
Astronomers have studied the Sun and probed its dynamic surface and energetic atmosphere in many ways through the centuries. But, to achieve a fuller understanding, astronomers need to study it across the entire electromagnetic spectrum, including the millimetre and submillimetre portion that ALMA can observe.
Hubble Finds Big Brother of Halley’s Comet – Ripped Apart By White Dwarf
February 9, 2017
European Space Agency News Release
Siyi Xu
European Southern Observatory
Garching bei München, Germany
Mathias Jäger
ESA/Hubble, Public Information Officer
Garching, Germany

The international team of astronomers observed the white dwarf WD 1425+540, about 170 light-years from Earth in the constellation Boötes (the Herdsman) [1]. While studying the white dwarf’s atmosphere using both the NASA/ESA Hubble Space Telescope and the W. M. Keck Observatory the team found evidence that an object rather like a massive comet was falling onto the star, getting tidally disrupted while doing so.
The team determined that the object had a chemical composition similar to the famous Halley’s Comet in our own Solar System, but it was 100,000 times more massive and had twice the proportion of water as its local counterpart. Spectral analysis showed that the destroyed object was rich in the elements essential for life, including carbon, oxygen, sulphur and even nitrogen [2].
NASA Television to Provide Coverage of European – Mission Comet Touchdown
NASA New Media Releaase
September 28, 2016
MEDIA ADVISORY M16-113

NASA Television and the agency’s website will air the conclusion of ESA’s (European Space Agency’s) Rosetta mission from 6:15 to 8 a.m. EDT Friday, Sept. 30, with NASA commentary, interviews and analysis of the successful mission. The Rosetta mission will end with the controlled decent of the spacecraft onto the surface of comet 67P/Churyumov-Gerasimenko at around 7:20 a.m.
From 8:15 to 10:15 a.m., NASA scientists and engineers involved in ESA’s Rosetta mission will be available for live broadcast interviews from the European Space Operations Center in Darmstadt, Germany.
Read the rest of this entry »
NASA Joins Forces to Put Satellite Eyes on Threat to U.S. Freshwater

NASA has joined forces with the U.S. Environmental Protection Agency, National Oceanic and Atmospheric Administration, and U.S. Geological Survey to transform satellite data designed to probe ocean biology into information that will help protect the American public from harmful freshwater algal blooms. Algal blooms are a worldwide environmental problem causing human and animal health risks, fish kills, and taste and odor in drinking water. In the United States, the cost of freshwater degraded by harmful algal blooms is estimated at $64 million annually. In August 2014, officials in Toledo, Ohio, banned the use of drinking water supplied to more than 400,000 residents after it was contaminated by an algal bloom in Lake Erie. The new $3.6 million, multi-agency effort will use ocean color satellite data to develop an early warning indicator for toxic and nuisance algal blooms in freshwater systems and an information distribution system to aid expedient public health advisories.
Ocean color satellite data from NASA’s Aqua, the USGS-NASA Landsat, and the European Space Agency’s Sentinel-2 and -3 are currently available to scientists, but are not routinely processed and produced in formats that help state and local environmental and water quality managers. Through this project, satellite data on harmful algal blooms developed by the partner agencies will be converted to a format that stakeholders can use through mobile devices and web portals.
NOAA and NASA pioneered the use of satellite data to monitor and forecast harmful algal blooms. Satellites allow for more frequent observations over broader areas than water sampling. The satellite data support NOAA’s existing forecasting systems in the Gulf of Mexico and Great Lakes.
The new network builds on previous NASA ocean satellite sensor technologies created to study the global ocean’s microscopic algal communities, which play a major role in ocean ecology, the movement of carbon dioxide between the atmosphere and ocean, and climate change. These sensors detect the color of the sunlit upper layer of the ocean and are used to create indicators that can help identify harmful algal blooms. Under certain environmental conditions, algae naturally present in marine and fresh waters rapidly multiply to create a bloom. Some species of algae called cyanobacteria produce toxins that can kill wildlife and domestic animals and cause illness in humans through exposure to contaminated freshwater and the consumption of contaminated drinking water, fish or shellfish. Cyanobacteria blooms are a particular concern because of their dense biomass, toxins, taste and odor.
The project also includes a research component to improve understanding of the environmental causes and health impacts of cyanobacteria and phytoplankton blooms across the United States. Blooms in lakes and estuaries are produced when aquatic plants receive excess nutrients under suitable environmental conditions. Various land uses, such as urbanization and agricultural practices, change the amount of nutrients and sediment delivered in watersheds, which can influence cyanobacterial growth. Researchers will compare the new freshwater algal blooms data with satellite records of land cover changes over time to identify specific land-use activities that may have caused environmental changes linked to the frequency and intensity of blooms. The results will help to develop better forecasts of bloom events. NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term satellite data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing. For more information on NASA’s Earth science activities, visit: http://www.nasa.gov/earth |