OSIRIS-REx spacecraft to asteroid 101955 Bennu today


This video from the USA says about itself:

OSIRIS-REx Tech – Surveying an Asteroid with Light

25 July 2016

NASA‘s OSIRIS-REx spacecraft is on a mission explore to near-Earth asteroid Bennu, a carbon-rich body that may contain clues to the origins of life. OSIRIS-REx is equipped with a suite of technologies designed to map and study Bennu in unprecedented detail. The OSIRIS-REx Visible and Infrared Spectrometer, or OVIRS, will look at the asteroid’s spectral signature to detect organics and other minerals. After OSIRIS-REx has thoroughly surveyed Bennu from orbit, will descend to the surface and collect a sample of the asteroid for return to Earth in 2023. In this video, OVIRS instrument scientists Dennis Reuter and Amy Simon discuss the challenges and rewards of sending a spectrometer into deep space.

Credit: NASA’s Goddard Space Flight Center/Dan Gallagher

From Science News in the USA:

OSIRIS-REx spacecraft launches tonight for mission to grab asteroid sample

by Christopher Crockett

6:00am, September 8, 2016

A spacecraft destined to bring samples of an asteroid back to Earth is scheduled to launch tonight. NASA’s OSIRIS-REx mission will launch September 8 at 7:05 p.m. EDT atop an Atlas V rocket from Cape Canaveral Air Force station in Florida. The probe will head for 101955 Bennu, a roughly 500-meter-wide asteroid whose 1.2-year orbit intersects that of Earth. Once the spacecraft arrives in late 2018, it will spend more than a year mapping the asteroid before reaching out and grabbing a sample in July 2020.

By bringing an asteroid sample to Earth, planetary scientists hope to learn more about the early solar system, what resources are available for future space explorers and how to knock off course any asteroids that pose a risk to Earth. Bennu itself has about a 1 in 2,700 chance of striking Earth late in the 22nd century.

To get a piece of Bennu, OSIRIS-REx will descend toward the surface and extend a robotic arm that will contact the surface for about 5 seconds. A puff of nitrogen gas will stir up rocks and soil, some of which will be collected in a container. The sample will be placed in a capsule for the ride home.

OSIRIS-REx will leave Bennu no earlier than March 2021. As it passes Earth in September 2023, the spacecraft will jettison its cargo, dropping the capsule in the Utah desert.

Jupiter’s north pole, first photo


This video from the USA says about itself:

Your First Look at Jupiter’s Gorgeous North Pole

2 September 2016

The Juno spacecraft has snapped the first photo ever of Jupiter’s north pole, revealing some intriguing surprises.

Sept. 2, 2016: Jupiter’s North Pole Unlike Anything Encountered in Solar System, by NASA: here.

‘Habitable’ planet discovery near solar system


This video says about itself:

Proxima b: an Earth-like planet on our cosmic doorstep

24 August 2016

We’ve found a planet orbiting in the habitable zone of our nearest star, Proxima Centauri, just 4.25 light years away. Here’s what we know about it so far.

From the European Southern Observatory:

Planet Found in Habitable Zone Around Nearest Star

Pale Red Dot campaign reveals Earth-mass world in orbit around Proxima Centauri

24 August 2016

Astronomers using ESO telescopes and other facilities have found clear evidence of a planet orbiting the closest star to Earth, Proxima Centauri. The long-sought world, designated Proxima b, orbits its cool red parent star every 11 days and has a temperature suitable for liquid water to exist on its surface. This rocky world is a little more massive than the Earth and is the closest exoplanet to us — and it may also be the closest possible abode for life outside the Solar System. A paper describing this milestone finding will be published in the journal Nature on 25 August 2016.

Just over four light-years from the Solar System lies a red dwarf star that has been named Proxima Centauri as it is the closest star to Earth apart from the Sun. This cool star in the constellation of Centaurus is too faint to be seen with the unaided eye and lies near to the much brighter pair of stars known as Alpha Centauri AB.

During the first half of 2016 Proxima Centauri was regularly observed with the HARPS spectrograph on the ESO 3.6-metre telescope at La Silla in Chile and simultaneously monitored by other telescopes around the world [1]. This was the Pale Red Dot campaign, in which a team of astronomers led by Guillem Anglada-Escudé, from Queen Mary University of London, was looking for the tiny back and forth wobble of the star that would be caused by the gravitational pull of a possible orbiting planet [2].

As this was a topic with very wide public interest, the progress of the campaign between mid-January and April 2016 was shared publicly as it happened on the Pale Red Dot website and via social media. The reports were accompanied by numerous outreach articles written by specialists around the world.

Guillem Anglada-Escudé explains the background to this unique search: “The first hints of a possible planet were spotted back in 2013, but the detection was not convincing. Since then we have worked hard to get further observations off the ground with help from ESO and others. The recent Pale Red Dot campaign has been about two years in the planning.”

The Pale Red Dot data, when combined with earlier observations made at ESO observatories and elsewhere, revealed the clear signal of a truly exciting result. At times Proxima Centauri is approaching Earth at about 5 kilometres per hour — normal human walking pace — and at times receding at the same speed. This regular pattern of changing radial velocities repeats with a period of 11.2 days. Careful analysis of the resulting tiny Doppler shifts showed that they indicated the presence of a planet with a mass at least 1.3 times that of the Earth, orbiting about 7 million kilometres from Proxima Centauri — only 5% of the Earth-Sun distance [3].

Guillem Anglada-Escudé comments on the excitement of the last few months: “I kept checking the consistency of the signal every single day during the 60 nights of the Pale Red Dot campaign. The first 10 were promising, the first 20 were consistent with expectations, and at 30 days the result was pretty much definitive, so we started drafting the paper!”

Red dwarfs like Proxima Centauri are active stars and can vary in ways that would mimic the presence of a planet. To exclude this possibility the team also monitored the changing brightness of the star very carefully during the campaign using the ASH2 telescope at the San Pedro de Atacama Celestial Explorations Observatory in Chile and the Las Cumbres Observatory telescope network. Radial velocity data taken when the star was flaring were excluded from the final analysis.

Although Proxima b orbits much closer to its star than Mercury does to the Sun in the Solar System, the star itself is far fainter than the Sun. As a result Proxima b lies well within the habitable zone around the star and has an estimated surface temperature that would allow the presence of liquid water. Despite the temperate orbit of Proxima b, the conditions on the surface may be strongly affected by the ultraviolet and X-ray flares from the star — far more intense than the Earth experiences from the Sun [4].

Two separate papers discuss the habitability of Proxima b and its climate. They find that the existence of liquid water on the planet today cannot be ruled out and, in such case, it may be present over the surface of the planet only in the sunniest regions, either in an area in the hemisphere of the planet facing the star (synchronous rotation) or in a tropical belt (3:2 resonance rotation). Proxima b’s rotation, the strong radiation from its star and the formation history of the planet makes its climate quite different from that of the Earth, and it is unlikely that Proxima b has seasons.

This discovery will be the beginning of extensive further observations, both with current instruments [5] and with the next generation of giant telescopes such as the European Extremely Large Telescope (E-ELT). Proxima b will be a prime target for the hunt for evidence of life elsewhere in the Universe. Indeed, the Alpha Centauri system is also the target of humankind’s first attempt to travel to another star system, the StarShot project.

Guillem Anglada-Escudé concludes: “Many exoplanets have been found and many more will be found, but searching for the closest potential Earth-analogue and succeeding has been the experience of a lifetime for all of us. Many people’s stories and efforts have converged on this discovery. The result is also a tribute to all of them. The search for life on Proxima b comes next…”

Notes

[1] Besides data from the recent Pale Red Dot campaign, the paper incorporates contributions from scientists who have been observing Proxima Centauri for many years. These include members of the original UVES/ESO M-dwarf programme (Martin Kürster and Michael Endl), and exoplanet search pioneers such as R. Paul Butler. Public observations from the HARPS/Geneva team obtained over many years were also included.

[2] The name Pale Red Dot reflects Carl Sagan’s famous reference to the Earth as a pale blue dot. As Proxima Centauri is a red dwarf star it will bathe its orbiting planet in a pale red glow.

[3] The detection reported today has been technically possible for the last 10 years. In fact, signals with smaller amplitudes have been detected previously. However, stars are not smooth balls of gas and Proxima Centauri is an active star. The robust detection of Proxima b has only been possible after reaching a detailed understanding of how the star changes on timescales from minutes to a decade, and monitoring its brightness with photometric telescopes.

[4] The actual suitability of this kind of planet to support water and Earth-like life is a matter of intense but mostly theoretical debate. Major concerns that count against the presence of life are related to the closeness of the star. For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. The planet’s atmosphere might also slowly be evaporating or have more complex chemistry than Earth’s due to stronger ultraviolet and X-ray radiation, especially during the first billion years of the star’s life. However, none of the arguments has been proven conclusively and they are unlikely to be settled without direct observational evidence and characterisation of the planet’s atmosphere. Similar factors apply to the planets recently found around TRAPPIST-1.

[5] Some methods to study a planet’s atmosphere depend on it passing in front of its star and the starlight passing through the atmosphere on its way to Earth. Currently there is no evidence that Proxima b transits across the disc of its parent star, and the chances of this happening seem small, but further observations to check this possibility are in progress.

More information

This research is presented in a paper entitled “A terrestrial planet candidate in a temperate orbit around Proxima Centauri”, by G. Anglada-Escudé et al., to appear in the journal Nature on 25 August 2016.

The team is composed of Guillem Anglada-Escudé (Queen Mary University of London, London, UK), Pedro J. Amado (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), John Barnes (Open University, Milton Keynes, UK), Zaira M. Berdiñas (Instituto de Astrofísica de Andalucia – CSIC, Granada, Spain), R. Paul Butler (Carnegie Institution of Washington, Department of Terrestrial Magnetism, Washington, USA), Gavin A. L. Coleman (Queen Mary University of London, London, UK), Ignacio de la Cueva (Astroimagen, Ibiza, Spain), Stefan Dreizler (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), Michael Endl (The University of Texas at Austin and McDonald Observatory, Austin, Texas, USA), Benjamin Giesers (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), Sandra V. Jeffers (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), James S. Jenkins (Universidad de Chile, Santiago, Chile), Hugh R. A. Jones (University of Hertfordshire, Hatfield, UK), Marcin Kiraga (Warsaw University Observatory, Warsaw, Poland), Martin Kürster (Max-Planck-Institut für Astronomie, Heidelberg, Germany), María J. López-González (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), Christopher J. Marvin (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), Nicolás Morales (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), Julien Morin (Laboratoire Univers et Particules de Montpellier, Université de Montpellier & CNRS, Montpellier, France), Richard P. Nelson (Queen Mary University of London, London, UK), José L. Ortiz (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), Aviv Ofir (Weizmann Institute of Science, Rehovot, Israel), Sijme-Jan Paardekooper (Queen Mary University of London, London, UK), Ansgar Reiners (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), Eloy Rodriguez (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), Cristina Rodriguez-Lopez (Instituto de Astrofísica de Andalucía – CSIC, Granada, Spain), Luis F. Sarmiento (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany), John P. Strachan (Queen Mary University of London, London, UK), Yiannis Tsapras (Astronomisches Rechen-Institut, Heidelberg, Germany), Mikko Tuomi (University of Hertfordshire, Hatfield, UK) and Mathias Zechmeister (Institut für Astrophysik, Georg-August-Universität Göttingen, Göttingen, Germany).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. 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, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links

Signs of planet detected around sun’s nearest neighbor star. Proxima Centauri companion orbits in habitable zone: here.

Growing plants on Mars?


This video from Leiden University in the Netherlands says about itself:

A Garden on Mars

22 August 2016

We are the Leiden iGEM 2016 team. In context of the iGEM competition, we are raising money through crowdfunding to support our research! You can support us by donation via the website, or you can support us by sharing this video and spreading the word.

From Leiden University in the Netherlands:

‘A garden on Mars‘ crowdfunding campaign starts today

22 August 2016

Today, 13 students at Leiden University have started a crowdfunding campaign to collect money for research into the possibilities of growing crops on Mars. Their research will contribute to the knowledge of our galaxy. The project is in the context of the iGEM competition.

Food for Martians

Martian soil contains a toxin known as perchlorate, which causes all crops grown to be toxic to humans. If we manage to land men on Mars in the near future, this is a problem that will have to be resolved. It is not possible to take adequate supplies of food, and crops therefore have to be grown as a sustainable source of nutrition. The students are developing a bacterial system that will break down perchlorate and at the same time release much-needed oxygen in the process: a win-win situation for future Martian explorers. The bacteria will do their work in the enclosed environment of a bioreactor with Martian soil.

Students and the public work together to enable research

The project is completely student led and student run. This includes financing their own materials, including perchlorate, simulated Martian soil and laboratory disposables. State-of-the-art techniques are used, including Martian gravity simulation. The students hope to finance a part of the costly project through crowdfunding. Communication is a key aspect of the project and the students are presenting their project at events, including the Night of Art and Knowledge on September 17.

International science competition

The students’ research is part of the world’s biggest competition in synthetic biology: the international Genetically Engineered Machine (iGEM) competition, organised by the prestigious Massachusetts Institute of Technology. In total, over 300 teams are participating in the competition, using synthetic biology to solve a problem of their own choosing. The results will be announced at the end of October 2016 at the Giant Jamboree in Boston.

Crowdfunding campaign

The crowdfunding starts on 22 August 2016 and will continue until the students travel to Boston on 27 October. Their target is €8,600, the amount they need to complete their research.

Perseid meteor shower in the USA, videos


This video from the USA says about itself:

12 August 2016

The Grand Daddy of all Perseid Meteors 180 degrees horizon to horizon over a brief break in the clouds in the Great Smoky Mountains. Perseid Meteor Shower 2016. This meteor lasted 180 seconds!! Filmed with Canon T5i 18mm f3.5 ISO 800 25 sec exposure with five second delays – six frames began at 503 AM EDT ended 506 AM EDT moving north to south.

This video from the USA says about itself:

12 August 2016

Time lapse of very long-lasting Perseid Meteor over the Great Smoky Mountains during a very brief window when there were no clouds. This meteor lasted for six frames from horizon to horizon – that is between 150 and 180 seconds long!

Filmed with Canon T5i 18mm f3.5 ISO800 25 sec exposure began 503 AM EDT ended 506 AM EDT moving north to south.

Perseids on Dutch Texel island: here.

‘Venus was once habitable’


Venus from space. Weinbaum’s Venus has a 500-m...

Venus from space. Weinbaum’s Venus has a 500-mile-wide habitable zone on the sunward side of the terminator. (Photo credit: Wikipedia)

This video says about itself:

10 August 2016

Scientists have been proposing for years now that Venus might not have always been the hottest planet in the Solar System. Researchers have pointed out that once Venus was a habitable planet.

From daily The Independent in Britain today:

Venus may once have been habitable, Nasa says

Being too close to the sun caused its oceans to evaporate, leading to a build-up of carbon dioxide that produced runaway global warming and today’s temperatures of more than 460C.

From the American Geophysical Union blog:

11 August 2016

Climate modeling suggests Venus may have been habitable

By NASA GISS staff

Observations suggest Venus may have had water oceans in its distant past. A land-ocean pattern like that above was used in a climate model to show how storm clouds could have shielded ancient Venus from strong sunlight and made the planet habitable.

Venus may have had a shallow liquid-water ocean and habitable surface temperatures for up to 2 billion years of its early history, according to computer modeling of the planet’s ancient climate by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York.

The findings, published this week in the journal Geophysical Research Letters, were obtained with a model similar to the type used to predict future climate change on Earth.

“Many of the same tools we use to model climate change on Earth can be adapted to study climates on other planets, both past and present,” said Michael Way, a researcher at GISS and the paper’s lead author. “These results show ancient Venus may have been a very different place than it is today.”

Venus today is a hellish world. It has a crushing carbon dioxide atmosphere 90 times as thick as Earth’s. There is almost no water vapor. Temperatures reach 864 degrees Fahrenheit (462 degrees Celsius) at its surface.

Scientists long have theorized that Venus formed out of ingredients similar to Earth’s, but followed a different evolutionary path. Measurements by NASA’s Pioneer mission to Venus in the 1980s first suggested Venus originally may have had an ocean. However, Venus is closer to the sun than Earth and receives far more sunlight. As a result, the planet’s early ocean evaporated, water-vapor molecules were broken apart by ultraviolet radiation, and hydrogen escaped to space. With no water left on the surface, carbon dioxide built up in the atmosphere, leading to a so-called runaway greenhouse effect that created present conditions.

Previous studies have shown that how fast a planet spins on its axis affects whether it has a habitable climate. A day on Venus is 117 Earth days. Until recently, it was assumed that a thick atmosphere like that of modern Venus was required for the planet to have today’s slow rotation rate. However, newer research has shown that a thin atmosphere like that of modern Earth could have produced the same result. That means an ancient Venus with an Earth-like atmosphere could have had the same rotation rate it has today.

Another factor that impacts a planet’s climate is topography. The GISS team postulated ancient Venus had more dry land overall than Earth, especially in the tropics. That limits the amount of water evaporated from the oceans and, as a result, the greenhouse effect by water vapor. This type of surface appears ideal for making a planet habitable; there seems to have been enough water to support abundant life, with sufficient land to reduce the planet’s sensitivity to changes from incoming sunlight.

Way and his GISS colleagues simulated conditions of a hypothetical early Venus with an atmosphere similar to Earth’s, a day as long as Venus’ current day, and a shallow ocean consistent with early data from the Pioneer spacecraft. The researchers added information about Venus’ topography from radar measurements taken by NASA’s Magellan mission in the 1990s, and filled the lowlands with water, leaving the highlands exposed as Venusian continents. The study also factored in an ancient sun that was up to 30 percent dimmer. Even so, ancient Venus still received about 40 percent more sunlight than Earth does today.

“In the GISS model’s simulation, Venus’ slow spin exposes its dayside to the sun for almost two months at a time,” co-author and fellow GISS scientist Anthony Del Genio said. “This warms the surface and produces rain that creates a thick layer of clouds, which acts like an umbrella to shield the surface from much of the solar heating. The result is mean climate temperatures that are actually a few degrees cooler than Earth’s today.”

The research was done as part of NASA’s Planetary Science Astrobiology program through the Nexus for Exoplanet System Science (NExSS) program, which seeks to accelerate the search for life on planets orbiting other stars, or exoplanets, by combining insights from the fields of astrophysics, planetary science, heliophysics, and Earth science. The findings have direct implications for future NASA missions, such as the Transiting Exoplanet Survey Satellite and James Webb Space Telescope, which will try to detect possible habitable planets and characterize their atmospheres.

South African telescope discovers many galaxies


First image released by the MeerKAT radio telescope showing hundreds of previously undetected galaxies

From CNN:

Super telescope finds hundreds of previously undetectable galaxies

By James Griffiths

0725 GMT (1525 HKT) July 17, 2016

A South African radio telescope has revealed hundreds of galaxies in a tiny corner of the universe where only 70 had been seen before.

The images, taken by MeerKAT telescope, are an indication of the detail the southern hemisphere’s most powerful radio telescope may be able to provide when it is fully operational later this year.

At present, 16 of MeerKAT’s 64 dishes are scanning the skies. As well as its scientific goals, the project serves as a technological demonstration of South Africa’s capability to host the Square Kilometer Array, a huge multiradio-telescope project to be built in Australia and South Africa comprising dozens of dishes.

“Based on the results being shown today, we are confident that after all 64 dishes are in place, MeerKAT will be the world’s leading telescope of its kind until the advent of SKA,” Professor Justin Jonas, SKA South Africa chief technologist, said in a statement.

Square Kilometer Array

The SKA, intended to be operational by the 2020s, will consist of around 3,000 dishes spread across a one square kilometer (0.4 square mile) area and will allow astronomers to peer deeper into space than ever before.

SKA says it will have a discovery potential 10,000 times that of the most advanced modern instruments and will explore black holes, supernovae, dark energy and look into the origins of the universe.

More than 20 countries are members of SKA, with Australia and South Africa being the main bases of operation. The project is headquartered in the UK.

‘Exceptionally beautiful images’

MeerKAT’s images, taken of a patch of sky covering less than 0.01% of the total, reveal more than 1,300 galaxies in the distant universe, where only around 70 had been previously detected.

They include a galaxy around 200 million light years away where new stars are being formed from hydrogen gas in large numbers, and a massive black hole spewing out jets of powerful electrons moving at close to the speed of light.

A “Fanaroff-Riley Class 2” (FR2) object: a massive black hole in the distant universe (matter falling into it produces the bright dot at the center) launching jets of powerful electrons moving at close to the speed of light.

“Today’s exceptionally beautiful images … demonstrate that MeerKAT has joined the big leagues of world radio astronomy,” said Fernando Camilo, SKA South Africa chief scientist.