Institute of Astronomy

Astronomy News

Smoky mass map weighs fat ancient galaxy cluster

4 April 2014 - 5:11pm
It's not something in your eye. It's not smoke from a late-night barbecue. You're looking at a map of the most massive ancient galaxy cluster ever seen
    





Gaia Live in School: Inspiring the next generation of European Space Scientists

4 April 2014 - 12:03pm

Students following 'Gaia Live in School' event

Will Gaia discover planets that humans would be able to live on? What is a quasar? How many people are actually working on the mission at the moment? These are just some of the varied questions that school students put to some of ESA’s Gaia experts during the Gaia Live in School Event on 25 March 2014.

More than 2000 students, mainly aged 10-12 years old, from 34 schools in 10 European countries followed a live webcast from the Gaia mission planning room at ESOC, ESA’s spacecraft operations centre in Germany. This special webcast gave students a unique opportunity to see behind the scenes of the Gaia mission, with Timo Prusti, the Gaia Project Scientist, and David Milligan, the Gaia Spacecraft Operations Manager answering many of the students’ questions.

Each school participating in the Gaia Live event was linked to a leading research institute in its area. On the day of the event, two postgraduate students, the ‘Gaia Explainers’ from each institute, went into the schools to deliver lively and interactive presentations about Gaia. Hands-on demonstrations and videos introduced the school students to the mission, and to key concepts such as the Solar System, the Milky Way and parallax, to aid their understanding of the science of Gaia before linking up to the live webcast.

Thumbs up at 'Gaia Live in School' event

In the first part of the live webcast students watched David Milligan describe Gaia’s journey to its orbit about L2, a gravitational equilibrium point that is 1.5 kilometres from Earth, how the spacecraft is operated, and how data are sent to and from the satellite. Timo Prusti continued by explaining why it is important to make a 3D map of the Milky Way, how Gaia will help to reveal our Galaxy’s history, and the other exciting discoveries Gaia will make.

Timo and David then answered a range of excellent questions from the schools, which had been submitted in advance of the event. The webcast further stimulated the students’ curiosity, and even more questions for the experts came streaming in from all 34 schools to ESOC by web chat – as many as possible were answered live on air.

Following the webcast, the postgraduate students completed their sessions in the schools with another question and answer session, as well as further demonstrations and activities.

Finnish students participating in 'Gaia Live in Schools' event

In preparation for the event the postgraduate students participated in an intensive training course, held at ESTEC, where they explored how to present science concepts to groups of school students. Working together with the teachers involved at each school, the local event programmes were adapted to ensure that they were relevant for each participating school audience. The enthusiasm of the teachers helped ensure the success of the event at each school.

The event was organised as a partnership between the Gaia Research for European Astronomy Training Network (GREAT) and ESA, with many of the ‘Gaia Explainers’ being students in the GREAT Initial Training Network.

 

Watch the replay of the ESOC part of the Gaia Live event here.

For more information about the event and the schools taking part, visit the GREAT event web page.

Authors: Rebecca Barnes (HE Space Operations for ESA), Nicholas Walton (Institute of Astronomy, University of Cambridge)

VIDEO: Saturn moon hides 'great lake'

3 April 2014 - 10:58pm
The evidence for an ocean of water under the surface of one of Saturn's moons is overwhelming, according to scientists. Pallab Ghosh reports.

Deep Ocean Detected Inside Saturn's Moon

3 April 2014 - 10:21pm
NASA's Cassini spacecraft and Deep Space Network have uncovered evidence that Saturn's moon Enceladus harbors a large underground ocean of liquid water, furthering scientific interest in the moon as a potential home to extraterrestrial microbes.

Saturn moon hides 'great lake'

3 April 2014 - 7:33pm
New measurements by Nasa's Cassini probe suggest Saturn's moon Enceladus hides a mass of liquid water as big as Lake Superior under its icy surface.

Hubble Finds That Monster 'El Gordo' Galaxy Cluster Is Bigger Than Thought

3 April 2014 - 7:00pm

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If someone told you there was an object in space called "El Gordo" (Spanish for "the fat one") you might imagine some kind of planet-eating monster straight out of a science fiction movie. The nickname refers to a monstrous cluster of galaxies that is being viewed at a time when the universe was just half of its current age of 13.8 billion years. This is an object of superlatives. It contains several hundred galaxies swarming around under a collective gravitational pull. The total mass of the cluster, and refined in new Hubble measurements, is estimated to be as much as 3 million billion stars like our Sun (about 3,000 times more massive than our own Milky Way galaxy) though most of the mass is hidden away as dark matter. The cluster may be so huge because it is the result of a titanic collision and merger between two separate galaxy clusters. Thankfully, our Milky Way galaxy grew up in an uncluttered backwater region of the universe.

Cassini-Huygens:Icy moon Enceladus has underground sea

3 April 2014 - 7:00pm
Saturn's icy moon Enceladus has an underground sea of liquid water, according to the international Cassini spacecraft.

Buried 'Lake Superior' seen on Saturn's moon Enceladus

3 April 2014 - 7:00pm
Gravity readings suggest that the jets Enceladus spits out come from a deep ocean in contact with a rocky core, raising hopes that the moon hosts life
    





NASA Space Assets Detect Ocean inside Saturn Moon

3 April 2014 - 5:00pm
NASA's Cassini spacecraft and Deep Space Network have uncovered evidence Saturn's moon Enceladus harbors a large underground ocean of liquid water, furthering scientific interest in the moon as a potential home to extraterrestrial microbes.

NASA Satellite to Continue Gathering Data Up to Planned Lunar Impact

3 April 2014 - 5:00pm
NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft is gradually lowering its orbital altitude to continue making science observations prior to its planned impact on the moon’s surface on or before April 21.

NASA Hubble Team Finds Monster "El Gordo" Galaxy Cluster Bigger Than Thought

3 April 2014 - 5:00pm
NASA's Hubble Space Telescope has weighed the largest known galaxy cluster in the distant universe, catalogued as ACT-CL J0102-4915, and found it definitely lives up to its nickname -- El Gordo (Spanish for "the fat one").

Radioactive waste used to peek inside a star explosion

3 April 2014 - 4:00pm
Scrap from an old particle accelerator helps solve riddle of how chemical elements are created in supernovae
    





Treasures of the RAS: Urania's Mirror (1824) This beautiful set of cards shows...

3 April 2014 - 2:02pm
Treasures of the RAS: Urania's Mirror (1824)

This beautiful set of cards shows the constellations. The bright stars have pin-pricked holes, so the layout of the night sky can be seen when the card is held up to a light.

https://www.youtube.com/watch?v=LgxEXV_LEAg
https://www.ras.org.uk/library/treasures-of-the-ras/2428-treasures-of-the-ras-urania-s-mirror


Treasures of the RAS: Urania's Mirror
A teaching aid for astronomy, Urania's Mirror, published in 1824. Victorians could learn about the night sky using these pretty pictures of the constellation...

Gaggle of dwarf planets found by dark energy camera

2 April 2014 - 11:12pm
Designed to study distant galaxies, the world's largest digital camera is also uncovering faint, distant worlds on the outskirts of the solar system
    





Galactic Serial Killer

2 April 2014 - 11:00am
This new image from the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile shows two contrasting galaxies: NGC 1316, and its smaller neighbour NGC 1317. These two are quite close to each other in space, but they have very different histories. The small spiral NGC 1317 has led an uneventful life, but NGC 1316 has engulfed several other galaxies in its violent history and shows the battle scars.

Solar system: Cracking up on asteroids

2 April 2014 - 1:00am

Solar system: Cracking up on asteroids

Nature 508, 7495 (2014). doi:10.1038/nature13222

Authors: Heather A. Viles

A combination of laboratory experiments and modelling shows that diurnal temperature variations are the main cause of rock breakdown and the ensuing formation of powdery rubble on the surface of small asteroids. See Letter p.233

Thermal fatigue as the origin of regolith on small asteroids

2 April 2014 - 1:00am

Thermal fatigue as the origin of regolith on small asteroids

Nature 508, 7495 (2014). doi:10.1038/nature13153

Authors: Marco Delbo, Guy Libourel, Justin Wilkerson, Naomi Murdoch, Patrick Michel, K. T. Ramesh, Clément Ganino, Chrystele Verati & Simone Marchi

Space missions and thermal infrared observations have shown that small asteroids (kilometre-sized or smaller) are covered by a layer of centimetre-sized or smaller particles, which constitute the regolith. Regolith generation has traditionally been attributed to the fall back of impact ejecta and by the break-up of boulders by micrometeoroid impact. Laboratory experiments and impact models, however, show that crater ejecta velocities are typically greater than several tens of centimetres per second, which corresponds to the gravitational escape velocity of kilometre-sized asteroids. Therefore, impact debris cannot be the main source of regolith on small asteroids. Here we report that thermal fatigue, a mechanism of rock weathering and fragmentation with no subsequent ejection, is the dominant process governing regolith generation on small asteroids. We find that thermal fragmentation induced by the diurnal temperature variations breaks up rocks larger than a few centimetres more quickly than do micrometeoroid impacts. Because thermal fragmentation is independent of asteroid size, this process can also contribute to regolith production on larger asteroids. Production of fresh regolith originating in thermal fatigue fragmentation may be an important process for the rejuvenation of the surfaces of near-Earth asteroids, and may explain the observed lack of low-perihelion, carbonaceous, near-Earth asteroids.

Rare exoplanet alignment set for April Fool's Day 2026

1 April 2014 - 6:00am
A distant solar system will be the arena for an unusual celestial arrangement, one sure to please Scrabble players as well as astronomers
    





Cosmology: Polar star

31 March 2014 - 1:00am

Cosmology: Polar star

Nature 508, 7494 (2014). http://www.nature.com/doifinder/10.1038/508028a

Author: Ron Cowen

After years of work in the Antarctic, John Kovac and his team have captured strong evidence for a long-held theory about the Universe’s birth.

Comet lander checks in with Earth

28 March 2014 - 3:58pm
The Philae lander, which Europe hopes to put on the surface of a comet later this year, is re-activated after three years in deep-space hibernation.