Institute of Astronomy

Feed aggregator

NASA funds radical Pluto hopper and cosmic echolocation concepts

Astronomy News - 10 April 2017 - 9:10am

The space agency just announced the recipients of its Innovative Advanced Concepts programme, which kickstarts researchers’ so-crazy-it-just-might-work ideas

ALMA Captures Dramatic Stellar Fireworks

Astronomy News - 10 April 2017 - 9:09am
Stellar explosions are most often associated with supernovae, the spectacular deaths of stars. But new ALMA observations provide insights into explosions at the other end of the stellar life cycle, star birth. Astronomers captured these dramatic images as they explored the firework-like debris from the birth of a group of massive stars, demonstrating that star formation can be a violent and explosive process too.

Violent end as young stars dramatically collide

Astronomy News - 10 April 2017 - 9:08am

Scientists capture a dramatic collision between two young stars that tore apart their stellar nursery.

Galactic garbage

Astronomy News - 10 April 2017 - 9:07am

Millions of pieces of human-made trash are orbiting the Earth. Some are tiny, but all pose a risk.

Atmosphere containing water detected around rocky exoplanet

Astronomy News - 7 April 2017 - 9:05am

An exoplanet just 1.4 times the size of Earth has an atmosphere containing water and methane, new observations show

An All-Nighter with Planet Jupiter

Astronomy News - 7 April 2017 - 9:05am
Video Length: 3:36

Stop what you’re doing and mark your calendar. Jupiter can be viewed at opposition from sunset on April 7, 2017 to sunrise on April 8, 2017.

Read this story

Downloadable Link: An All-nighter with Planet Jupiter - mp4YouTubeVimeo

Tiny Thrusters Demonstrate a Capability Needed to Detect Gravitational Waves

Astronomy News - 7 April 2017 - 9:03am

Technology Infused: On December 3, 2015, the LISA Pathfinder mission blasted into space carrying the most stable spacecraft thruster system ever qualified for use in space. Developed by NASA JPL, the Space Technology 7 (ST-7) Disturbance Reduction System (DRS) is designed to control the spacecraft’s position to within a millionth of a millimeter. ST-7 DRS consists of clusters of colloid micronewton thrusters and control software residing on a dedicated computer. To operate, the thrusters apply an electric charge to small droplets of liquid and accelerate them through an electric field. This new thruster technology has never successfully been used in space before. ST-7 DRS will deliver extremely small pulses of energy (5 to 30 micronewtons of thrust) to precisely control the LISA Pathfinder spacecraft.

This cluster of four colloid thrusters is part of the Disturbance Reduction
System, developed by NASA/JPL, which will help keep the LISA Pathfinder

spacecraft extremely stable. (Image credit: ESA/NASA/JPLCaltech)  

Impact: Precise spacecraft control is vital to achieve the LISA Pathfinder goal: demonstrating technology concepts required to detect low-frequency gravitational waves. Gravitational waves are incredibly faint. The magnitude of oscillation is on the order of tens of picometers—one picometer is one trillionth of a meter—which is why it is critical to keep the spacecraft stable enough to detect the waves. The LISA Pathfinder contains two test masses— objects designed to respond only to gravity (to the greatest extent possible). These test masses are made of a mixture of gold and platinum so that they will be very dense, but also non-magnetic. They each weigh about 4 pounds (2 kilograms) and measure 1.8 inches (4.6 centimeters) on each side. The LISA Pathfinder spacecraft is intended to shield the test masses from external forces so that they follow a trajectory determined only by the local gravitational field. The dominant force to overcome is solar pressure, which pushes on the spacecraft and is the equivalent of about the weight of a grain of sand. By precisely measuring the position of the freely floating test masses, the ST-7 DRS uses its “micro-rocket” thrusters to keep the spacecraft centered about the test masses. In effect, the spacecraft essentially flies in formation with the test masses, using onboard sensor information (provided by the European LISA Technology Package) to control the thrusters and keep the test masses totally isolated from external forces. By measuring their relative motion, a future mission could use such test masses as references in the quest to detect gravity waves.

The LISA Pathfinder spacecraft will help pave the way for a mission to detect gravitational
waves. NASA/JPL developed a thruster system onboard. (Image credit: ESA)  

Status and Future Plans: ST-7 DRS is one of two thruster systems being tested on the LISA Pathfinder mission (the other system was developed by the European Space Agency). If successful, there are numerous potential uses for this technology in the future. For example, the system could be used to stabilize a future spacecraft that needs to be very still to detect exoplanets. ST-7 DRS could replace the reaction wheels that help control a spacecraft’s orientation, reducing the overall mass of the spacecraft. The thruster system could also be used to enable spacecraft to fly in formation. For example, a constellation of small satellites flying together could use these thrusters to remain highly synchronized.

Sponsoring Organization: The Astrophysics Division provided funding via the SAT program to PI John Ziemer at NASA JPL to support development of the ST-7 DRS.

Master Image: 

Exoplanet mission gets ticket to ride

Astronomy News - 7 April 2017 - 9:01am

A Soyuz rocket operated by Arianespace from Europe's spaceport in Kourou will boost ESA's upcoming exoplanet satellite into space.

Hubble takes close-up portrait of Jupiter [heic1708]

Astronomy News - 7 April 2017 - 9:01am

During April 2017 Jupiter is in opposition: it is at its closest to Earth and the hemisphere facing Earth is fully illuminated by the Sun. The NASA/ESA Hubble Space Telescope used this special configuration to capture an image of what is by far the largest planet in the Solar System. This image adds to many others made in the past, and together they allow astronomers to study changes in the atmosphere of the gas giant.

Atmosphere found around Earth-like planet GJ 1132b

Astronomy News - 7 April 2017 - 9:00am

Astronomers make the first detection of an atmosphere surrounding a "super-Earth" planet.

Earth-sized telescope set to snap first picture of a black hole

Astronomy News - 6 April 2017 - 9:20am

The Event Horizon Telescope will take images of the black hole at the centre of our galaxy, and could reveal how relativity and quantum mechanics mesh

A massive, quiescent galaxy at a redshift of 3.717

Astronomy News - 6 April 2017 - 9:18am

A massive, quiescent galaxy at a redshift of 3.717

Nature 544, 7648 (2017). doi:10.1038/nature21680

Authors: Karl Glazebrook, Corentin Schreiber, Ivo Labbé, Themiya Nanayakkara, Glenn G. Kacprzak, Pascal A. Oesch, Casey Papovich, Lee R Spitler, Caroline M. S. Straatman, Kim-Vy H. Tran & Tiantian Yuan

Finding massive galaxies that stopped forming stars in the early Universe presents an observational challenge because their rest-frame ultraviolet emission is negligible and they can only be reliably identified by extremely deep near-infrared surveys. These surveys have revealed the presence of massive, quiescent early-type galaxies appearing as early as redshift z ≈ 2, an epoch three billion years after the Big Bang. Their age and formation processes have now been explained by an improved generation of galaxy-formation models, in which they form rapidly at z ≈ 3–4, consistent with the typical masses and ages derived from their observations. Deeper surveys have reported evidence for populations of massive, quiescent galaxies at even higher redshifts and earlier times, using coarsely sampled photometry. However, these early, massive, quiescent galaxies are not predicted by the latest generation of theoretical models. Here we report the spectroscopic confirmation of one such galaxy at redshift z = 3.717, with a stellar mass of 1.7 × 1011 solar masses. We derive its age to be nearly half the age of the Universe at this redshift and the absorption line spectrum shows no current star formation. These observations demonstrate that the galaxy must have formed the majority of its stars quickly, within the first billion years of cosmic history in a short, extreme starburst. This ancestral starburst appears similar to those being found by submillimetre-wavelength surveys. The early formation of such massive systems implies that our picture of early galaxy assembly requires substantial revision.

NASA’s Cassini Mission Prepares for 'Grand Finale' at Saturn

Astronomy News - 5 April 2017 - 9:07am
Portal origin URL: NASA’s Cassini Mission Prepares for 'Grand Finale' at SaturnPortal origin nid: 399549Published: Tuesday, April 4, 2017 - 15:09Featured (stick to top of list): noPortal text teaser: NASA's Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission’s grand finale.Portal image: This illustration shows NASA’s Cassini spacecraft above Saturn's northern hemisphere prior to one of its 22 grand finale dives. Science Categories: Solar System

NASA’s Cassini Mission Prepares for 'Grand Finale' at Saturn

Astronomy News - 5 April 2017 - 9:06am
NASA's Cassini spacecraft, in orbit around Saturn since 2004, is about to begin the final chapter of its remarkable story. On Wednesday, April 26, the spacecraft will make the first in a series of dives through the 1,500-mile-wide (2,400-kilometer) gap between Saturn and its rings as part of the mission’s grand finale.

Rosetta's intimate portrait of a comet: read all about it

Astronomy News - 5 April 2017 - 9:04am

Rosetta's pioneering mission to explore a comet in unprecedented detail completed operations last year. As the science continues, members of the public, as well as scientists, can freely access hundreds of papers that reveal the comet's secrets. A special issue of Monthly Notices of the Royal Astronomical Society is the latest journal to provide this service.

Oldest dust ever spotted in the universe seen in distant galaxy

Astronomy News - 4 April 2017 - 9:11am

We’ve spotted dust in a galaxy whose light reaches us from when the universe was only 600 million years old – a game changer for studying the earliest galaxies

NASA orbiter shows Mars lost 90 per cent of its CO2 to space

Astronomy News - 3 April 2017 - 9:08am

The MAVEN spacecraft has completed the key part of its mission: to track down how much argon Mars’s atmosphere is giving up as a proxy for carbon dioxide loss

Gravitational waves slow the spin of shape-shifting neutron star

Astronomy News - 3 April 2017 - 9:08am

A tiny bump on a star could change how it rotates and possibly explain why there seems to be a speed limit for spinning neutron stars

Mapping Hydrogen to Locate Water on the Moon

Astronomy News - 3 April 2017 - 9:07am

Technology Infused: The Lunar polar Hydrogen Mapper (LunaH-Map) mission is a CubeSat that will detect the amount of hydrogen at the moon’s South Pole.

LunaH-Map Spacecraft Design (cutaway views).

Designed to fly around the moon in a polar orbit at low altitude (5-12 km), LunaH-Map will carry two newly designed neutron spectrometers to produce highresolution maps of near-surface hydrogen. Previous moon missions have indicated that there is an abundance of hydrogen near the lunar poles, but the exact locations were not determined.

The presence of hydrogen indicates the presence of water, and LunaHMap will provide important constraints on the location and abundance of ice deposits near the lunar South Pole. The spectrometers on LunaH-Map will measure the energies of neutrons that have interacted with and subsequently leaked back out of the material in the top meter of the lunar surface. To accomplish this task, the mission will employ new technology—an elpasolite scintillation detector—in an array of neutron detectors mounted to one face of the spacecraft. These new detectors enable efficient neutron detection capability in a small package, making them ideal for use on a CubeSat platform.

Impact: LunaH-Map will produce maps of hydrogen abundance with the highest spatial resolution ever acquired by a neutron detector from orbit, and will demonstrate the capability of a CubeSat platform to acquire neutron counts from planetary surfaces. Understanding the distribution of hydrogen on the surface of the moon will help NASA plan future missions to the moon, especially missions that will land on the surface. Knowing the location and volume of ice deposits will also be vital to future moon missions that plan to make use of in situ resources—for example, a human mission to the moon. LunaH-Map will also use a highly efficient ion propulsion system to maneuver itself from the Space Launch System (SLS) into a stable lunar orbit, and finally a science mapping orbit. LunaH-Map and Lunar IceCube will be the first two interplanetary CubeSats to demonstrate this technology in space on a small spacecraft platform.

Orbit ground track shown in red for the entire 60 (Earth) day LunaH-Map science phase:141 passes over target area initially (and periodically) centered on Shackleton Crater withclose-approach of 5 km at each perilune crossing. Yellow circle denotes LunaH-Mapaltitude of 8 km; green circle denotes LunaH-Map altitude of 12 km.

 

Status and Future Plans: LunaH-Map is one of 13 CubeSats scheduled for launch on the first integrated flight of NASA’s Space Launch System and Orion spacecraft in 2018. LunaH-Map is being designed, built, and tested at Arizona State University. Industry partners will design, build, and deliver the spectrometers for integration into the spacecraft.

Busek’s 65W iodine-fueled ion propulsion system “BIT-3,” currently scheduled to fly onthe LunaH-Map and Lunar IceCube missions.

 

Sponsoring Organization: PSD provides funding for the LunaH-Map effort via the PICASSO program. PI, Craig Hardgrove, resides at Arizona State University. STMD’s SBIR program provides funding for technology development related to the detector component of the spectrometer to Radiation Monitoring Devices, Inc. and the ion propulsion system to Busek Co. Inc.

Master Image: 

Search for stellar survivor of a supernova explosion [heic1707]

Astronomy News - 3 April 2017 - 9:07am

Astronomers have used the NASA/ESA Hubble Space Telescope to observe the remnant of a supernova explosion in the Large Magellanic Cloud. Beyond just delivering a beautiful image, Hubble may well have traced the surviving remains of the exploded star's companion.