Archiv: Weltraumforschung / Beobachtung / Teleskope / Astronomie / space exploration / observation / telescopes / astronomy


21.10.2023 - 21:45 [ CNN ]

Psyche mission launches as NASA’s first trip to a metal world

(October 13, 2023)

To accomplish the rest of the mission, the van-size spacecraft will rely on its new solar electric propulsion system, powered by Hall-effect thrusters, Oh said. The thrusters will utilize the spacecraft’s large solar arrays and “use electricity to ionize xenon gas and accelerate those charged ions through an electric field to very, very high speeds,” Oh said. (…)

Also along for the ride is the Deep Space Optical Communications technology demonstration, or DSOC. Occurring during the first two years of the journey to Psyche, it will be NASA’s most distant experiment of high-bandwidth laser communications, testing the sending and receiving of data to and from Earth using an invisible near-infrared laser.

01.07.2023 - 17:20 [ Nature.com ]

Giant gravitational waves: why scientists are so excited

On 29 June, four separate teams of scientists made an announcement1–4 that promises to shake up astrophysics: they had seen strong hints of very long gravitational waves warping the Galaxy.

Gravitational waves are ripples in the fabric of space-time that are generated when large masses accelerate. They were first detected in 2015, but the latest evidence hints at ‘monster’ ripples with wavelengths of 0.3 parsecs (1 light year) or more; the waves detected until now have wavelengths of tens to hundreds of kilometres.

Here Nature reports what these monster gravitational waves could mean for our understanding of the cosmos, and how the field could evolve.

01.07.2023 - 17:05 [ New York Times ]

The Cosmos Is Thrumming With Gravitational Waves, Astronomers Find

(June 28, 2023)

The scientists strongly suspect that these gravitational waves are the collective echo of pairs of supermassive black holes — thousands of them, some as massive as a billion suns, sitting at the hearts of ancient galaxies up to 10 billion light-years away — as they slowly merge and generate ripples in space-time.

“I like to think of it as a choir, or an orchestra,” said Xavier Siemens, a physicist at Oregon State University who is part of the North American Nanohertz Observatory for Gravitational Waves, or NANOGrav, collaboration, which led the effort. Each pair of supermassive black holes is generating a different note, Dr. Siemens said, “and what we’re receiving is the sum of all those signals at once.”

01.07.2023 - 16:50 [ Institute of Physics - IOP.org ]

Searching for the Nano-Hertz Stochastic Gravitational Wave Background with the Chinese Pulsar Timing Array Data Release I

(Published 29 June 2023)

Observing and timing a group of millisecond pulsars with high rotational stability enables the direct detection of gravitational waves (GWs). The GW signals can be identified from the spatial correlations encoded in the times-of-arrival of widely spaced pulsar-pairs. The Chinese Pulsar Timing Array (CPTA) is a collaboration aiming at the direct GW detection with observations carried out using Chinese radio telescopes. This short article serves as a „table of contents“ for a forthcoming series of papers related to the CPTA Data Release 1 (CPTA DR1) which uses observations from the Five-hundred-meter Aperture Spherical radio Telescope. (…)

A Pulsar Timing Array (PTA; Foster & Backer 1990) is an array of pulsars, which are regularly observed. The times-of-arrival (TOAs) are measured for pulses that we see beams of electromagnetic waves emitted by the pulsars sweeping over the Earth. As the directions of the radiation beam and the pulsar rotational axis do not coincide, we observe this radiation as regular pulses synchronized to the pulsar rotation (Gold 1969).

04.10.2021 - 07:04 [ National Astronomical Observatory of Japan / SciTechdaily.com ]

Interplay Between Magnetic Force and Gravity in Massive Star Formation

(September 26, 2021)

The magnetic field is part of one of the four fundamental forces in nature. It plays a vital role in everyday life, from producing electricity in hydroelectric power plants to diagnosing diseases in medicine. Historically, the Earth’s magnetic field served as a compass for travelers before modern technology was available. Crucially for life, the Earth’s magnetic field acts as a shield protecting us from charged particles emanating from the Sun, which are accelerated by the Sun’s magnetic field. Removing this shield would very likely extinguish life on Earth.

22.09.2021 - 19:40 [ ORF ]

Riesiger Hohlraum im All entdeckt

Bei der Erstellung dreidimensionaler Karten in der Milchstraße haben Astrophysiker und Astrophysikerinnen einen riesigen Hohlraum entdeckt. Das kugelförmige Gebilde hat einen Durchmesser von rund 500 Lichtjahren.

15.07.2021 - 08:10 [ NationalGeographic.com ]

Surprise: Solar System „Force Field“ Shrinks Fast

(October 1, 2010)

It‘s cold, dusty, and bereft of planets, but the outskirts of our solar system are anything but dull, according to increasing evidence from NASA‘s Interstellar Boundary Explorer (IBEX) craft.

As charged particles flow out from the sun, they eventually bump up against interstellar medium—the relatively empty areas between stars. These interactions „inflate“ a protective bubble that shields Earth and the entire solar system from potentially harmful cosmic rays (solar system pictures).

15.07.2021 - 08:01 [ Massachusetts Institute of Technology (MIT) ]

The solar wind bubble that protects Earth has been mapped for the first time

Using data IBEX collected on ENAs as it charted just one 11-year solar cycle, the time between shifts in the sun’s magnetic field, researchers built a three-dimensional map of the entire heliosphere, which Reisenfeld says shields Earth and other planets from harmful radiation.

“Our Earth gets bombarded by cosmic rays, galactic cosmic rays all the time,” he says. These rays can subtly affect airplanes that fly near the poles, often on trips between Europe or Asia and the US.

Scientists say that to study other planet’s astrospheres, which is what heliospheres are called when they surround other stars, we must first understand our own.

10.07.2021 - 22:00 [ Max-Planck-Institut für Astronomie ]

Neu entdeckte Eis-Eigenschaften zeigen, wie im Weltraum organische Moleküle entstehen könnten

In einer Reihe von Experimenten präparierten die Forscher zunächst einen mehrschichtigen Wassereis-„Kern“ und legten dann, bei einer Temperatur von 6 Kelvin, unterschiedlich dicke Kohlenmonoxid-Eisschichten darauf. Anschließend erwärmten sie die Probe auf 20 Kelvin und beobachteten die ganze Zeit sorgfältig die Infrarotspektren.

08.07.2021 - 19:33 [ Netzpolitik.org ]

Der Sternenhimmel gehört uns allen – und nicht Elon Musk und Jeff Bezos

Bislang sendet die deutsche Politik das falsche Signal: Anstatt Sternenhimmel, Wissenschaft und den Zugang zum Weltall zu schützen, fördert sie den Zugang zum Satelliteninternet, um die Löcher in der deutschen Breitbandlandschaft zu stopfen.

29.06.2021 - 21:31 [ BBC ]

Rare black hole and neutron star collisions sighted twice in 10 days

When objects as massive as these collide they create ripples in the fabric of space called gravitational waves. And it is these ripples that the researchers have detected.

17.04.2021 - 04:46 [ CNN ]

Giant radio pulses and X-ray surges are coming from the Crab Nebula

The light from this supernova first reached Earth in July 1054 and was witnessed by astronomers in Japan and China.

When the star exploded, it formed a neutron star, which is the dense core of a star that is about the size of a city like Chicago. This became a pulsar, or rapidly spinning neutron star, that is now located in the nebula.

07.04.2021 - 21:33 [ France24 ]

Radio telescope reveals thousands of star-forming galaxies in early Universe

The LOFAR telescope combines signals from a huge network of more than 70,000 individual antennas in countries from Ireland to Poland, linked by a high-speed fiber optic network.

30.03.2021 - 21:48 [ France24 ]

Comet ‚most pristine‘ object from outer space seen in Solar System

Writing in the journal Nature Communications, an international team describe how 2I/Borisov‘s coma — the nebulous envelope around the nucleus of a comet — polarised light at a higher rate than typical comets.

10.03.2021 - 18:40 [ Independent.co.uk ]

Scientists detect radio blast coming from further away in space than ever before

More distant quasars have been found in the past. But the new one is notable because it is “radio-loud” – it is the first time that radio jets have been able to be detected from such a distant object.

Quasars are among the brightest objects in the universe. They are found at the centre of some galaxies nd are powered by supermassive black holes – when the surrounding gas is eaten by the black hole, it throws out energy that travels across the universe and can be studied by scientists.

20.02.2021 - 12:20 [ Jet Propulsion Laboratory / NASA.gov ]

Using Light to Study Planets

In this activity, students will build a spectrometer using basic materials to observe the light emitted and absorbed by several sources. This will be used as a model for how NASA uses spectroscopy to determine the nature of elements found on Earth and other planets. For higher grades, this activity can also be used to discuss advanced spectroscopic topics, such as how NASA research is advancing spectroscopic techniques to teach us more about plant life on Earth.

27.11.2020 - 22:14 [ France24 ]

Cyprus rocky testing ground for Mars

The CSEO is taking part in a major international research project on Mars, in collaboration with three other European countries as well as the United States.

27.09.2020 - 15:59 [ Ansa.it ]

Italy, USA sign moon-exploration agreement

Italy and the United States on Friday signed a declaration of intent for exploration of the moon linked to the Artemis programme.
The deal was signed in Rome by Cabinet Secretary Riccardo Fraccaro in video link with NASA Administrator Jim Bridenstine.

15.09.2020 - 12:40 [ Frankfurter Allgemeine Zeitung ]

Zum Venustransit: Leben in Säurewolken?

(07.06.2004)

Andere Astrobiologen haben dagegen noch grundsätzlichere Bedenken. Wenn es die venerischen Luftbazillen wirklich gäbe, so ihr Einwand, hätten sie oder ihre Stoffwechselprodukte in den Meßdaten der Venussonden schon lange auffallen müssen. „Wo Leben existieren kann, neigt es zu Dominanz“, sagt etwa der Nasa-Astrobiologe Chris McKay. „Wenn ich aus meinem Fenster blicke, sehe ich überall Grün – warum, bitte, sind die Venuswolken nicht grün?“

15.09.2020 - 12:32 [ BBC ]

Venus clouds ‚might harbour life‘

(25.05.2004)

„Current theories suggest that Venus and the Earth may have started out alike. There might have been a lot of water on Venus and there might have been a lot of carbon dioxide on Earth,“ Professor Ingersoll explained.

But all that was to change. On Earth, life in the oceans took in carbon dioxide and turned it into limestone. On Venus, 30% closer to the Sun, any oceans boiled away and the water vapour added to the runaway greenhouse effect.

15.09.2020 - 11:57 [ Harold Morowitz and Carl Sagan / Nature.com ]

Life in the Clouds of Venus?

(16.09.1967)

WHILE the surface conditions of Venus make the hypothesis of life there implausible, the clouds of Venus are a different story altogether. As was pointed out some years ago, water, carbon dioxide and sunlight—the prerequisites for photosynthesis—are plentiful in the vicinity of the clouds. Since then, good additional evidence has been provided that the clouds are composed of ice crystals at their tops and it seems likely that there are water droplets toward their bottoms. Independent evidence for water vapour also exists5.

15.09.2020 - 11:56 [ ScienceDirect.com ]

Water vapor in the atmosphere of Venus

(December 1972)

Infrared spectra of Venus produced by a Fourier spectrometer flown aboard the NASA CV 990 jet aircraft were analyzed for water-vapor content by comparison with calculated model spectra. The reflecting layer model gave an abundance of 1.6 ± 0.4 μ of precipitable water for the two-way transmission of the Venus atmosphere. The scattering model resulted in a value of 0.25 ± 0.10 μ of water per scattering mean free path.

15.09.2020 - 11:53 [ New York Times ]

Life on Venus? Astronomers See a Signal in Its Clouds

(14.09.2020)

“This is an astonishing and ‘out of the blue’ finding,” said Sara Seager, a planetary scientist at the Massachusetts Institute of Technology and an author of the papers (one published in Nature Astronomy and another submitted to the journal Astrobiology). “It will definitely fuel more research into the possibilities for life in Venus’s atmosphere.”

15.09.2020 - 11:31 [ Nature.com ]

Phosphine gas in the cloud decks of Venus

(14.09.2020)

Here we report the apparent presence of phosphine (PH3) gas in Venus’s atmosphere, where any phosphorus should be in oxidized forms. Single-line millimetre-waveband spectral detections (quality up to ~15σ) from the JCMT and ALMA telescopes have no other plausible identification.

24.08.2020 - 13:24 [ MIT Technology Review ]

The 5 best places to explore in the solar system—besides Mars

In studying Pluto, “we can get a sense of what goes on in the Kuiper belt, and how it’s able to produce these geologically active bodies that are so small and distant from the sun but still have enough internal energy to drive these processes,” says Karunatillake. Pluto could be a sign that just because another world is far away from the sun doesn’t mean it’s completely dead.

As with Ceres, however, there just hasn’t been enough time since the last mission to justify greenlighting a new one yet. We may need to wait another decade before NASA or another institution thinks it’s time to launch another spacecraft to Pluto.

24.08.2020 - 13:11 [ Phys.org ]

Dwarf planet Ceres is an ocean world: study

(10.08.2020)

Using infrared imaging, one team discovered the presence of the compound hydrohalite—a material common in sea ice but which until now had never been observed off of Earth.

24.08.2020 - 12:02 [ Heise.de ]

Beteigeuze wird schon wieder dunkler: Neuer Erklärungsversuch

(13.08.2020)

Zwischenzeitlich kam er nur auf 40 Prozent seiner normalen Helligkeit und hatte damit unter anderem Spekulationen genährt, dass sein Ende in einer gigantischen Explosion bevorstehen könnte. Immerhin ist unstrittig, dass er am Ende seines Lebens angekommen ist und in astronomisch naher Zukunft in einer immensen Supernova enden wird. Die wäre am Nachthimmel so hell wie ein Halbmond. Ende Februar begann er aber wieder heller zu werden, im späten Frühling war er wieder so hell wie früher.

24.08.2020 - 12:01 [ National Aeronautics and Space Administration ]

NASA Satellite’s Lone View of Betelgeuse Reveals More Strange Behavior

(13.08.2020)

STEREO’s measurements revealed that Betelgeuse is dimming again — an unexpected development so soon after its last dim period. Betelgeuse typically goes through brightness cycles lasting about 420 days, with the previous minimum in February 2020, meaning this dimming is happening unexpectedly early. These observations were reported by the science team via The Astronomer’s Telegram on July 28, 2020. This is an intriguing phenomenon that scientists will study with additional Earth-orbiting and ground-based observatories when Betelgeuse returns to the night sky in late August.

20.07.2020 - 13:25 [ Sloan Digital Sky Survey - SDSS.org ]

No need to Mind the Gap: Astrophysicists fill in 11 billion years of our universe’s expansion history

This map represents the combined effort of more than 20 years of mapping the Universe using the Sloan Foundation telescope. The cosmic history that has been revealed in this map shows that about six billion years ago, the expansion of the Universe began to accelerate, and has continued to get faster and faster ever since. This accelerated expansion seems to be due to a mysterious invisible component of the Universe called “dark energy,” consistent with Einstein’s General Theory of Relativity but extremely difficult to reconcile with our current understanding of particle physics.

20.07.2020 - 13:20 [ Blick.ch ]

Millionen Galaxien und Quasare analysiert: Forschende schaffen bisher grösste 3D-Karte des Universums

Im Projekt forschte das Team bis zu elf Milliarden Jahre zurück in die Vergangenheit. Dazu benutzten sie sogenannte Quasare – der aktive Kern einer Galaxie, deren supermassenreiches Schwarzes Loch in ihrem Zentrum durch die darin eingeschlossene Materie extrem hell wird.

Die Karte zeigt, dass sich die Expansion des Universums an einem bestimmten Punkt beschleunigt hat und seither anhält. Die Forschenden machen dafür dunkle Energie verantwortlich.

15.07.2020 - 16:55 [ Johan Hidding / Youtube ]

Large scale structure formation in the Universe simulated

Apr 2, 2009

This is a simulation of structure formation in the Universe using the adhesion approximation. The algorithm is described by Weinberg and Gunn in MNRAS in 1990

15.07.2020 - 16:54 [ Youtube ]

The Cosmic Web, or: What does the universe look like at a VERY large scale?

Nov 6, 2010

The Millennium Simulation featured in this clip was run in 2005 by the Virgo Consortium, an international group of astrophysicists from Germany, the United Kingdom, Canada, Japan and the United States.

15.07.2020 - 16:52 [ Vice.com ]

Scientists Discovered a Gigantic Structure in a Hidden Zone of Space

(today)

However, this particular structure is located in the “Zone of Avoidance,” which is the region of space right behind the dusty center of the Milky Way from our perspective on Earth. As a result, our galaxy’s bulk has blocked it from view—until now.

08.07.2020 - 11:13 [ ORF ]

Komet mit freiem Auge sichtbar

Derzeit zieht der Komet Neowise an der Erde vorbei. Er kommt unserem Planeten so nah, dass er und sein Schweif mit bloßem Auge sichtbar ist.

21.06.2020 - 18:44 [ NASA / Twitter ]

There’s a lot to spot in the sky this month. Turn an eye upwards to find:

The Northern Hemisphere’s #SummerSolstice in full swing
The Summer Triangle of stars in the East
Morning planetary views of Mars, Jupiter & Venus

And more!

20.05.2020 - 01:52 [ Ars Technica ]

NASA’s human spaceflight chief just resigned, and the timing couldn’t be worse

The timing of Doug Loverro‘s departure is terrible, with NASA‘s first launch of humans in nearly nine years due to occur in just eight days.

The space agency offered a bland statement regarding Loverro‘s resignation as Associate Administrator for Human Exploration and Operations (HEO) at NASA.

16.04.2020 - 03:18 [ Nature Astronomy ]

An extremely energetic supernova from a very massive star in a dense medium

Here we present a new event, SN2016aps, offset from the centre of a low-mass galaxy, that radiated ≳5 × 1051 erg, necessitating a hyper-energetic supernova explosion.

25.03.2020 - 01:01 [ ScienceAlert ]

Superconductivity Has Been Discovered in Meteorites For The First Time

Scientists have found naturally occurring superconducting materials in extraterrestrial objects for the first time, discovering superconductive grains embedded inside two distinct meteorites that crash-landed on Earth.