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Uranus image celebrates Herschel - the man and the machine
http://www.bbc.co.uk/news/science-environment-13389940
Happy Birthday H.
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Uranus image celebrates Herschel - the man and the machine
7 July 2011
ESA’s Herschel space observatory has discovered that titanic stellar explosions can be excellent dust factories. In space, the dust mixes with gas to become the raw material for new stars, planets and, ultimately, life. This discovery may solve a mystery of the early Universe.
The discovery was made while Herschel was charting emission from cold dust in the Large Magellanic Cloud, a small galaxy near to the Milky Way. It is the perfect observatory for the job because cold dust radiates far-infrared light, the wavelengths Herschel is designed to detect.
Herschel saw a spot of light at the location of supernova 1987A, an exploding star first seen from Earth in February 1987, and the closest known supernova in the past 400 years.
Since then, astronomers have been studying the remains of the explosion as its blast wave expands into its surroundings.
Herschel’s images are the first clear-cut far-infrared observations of SN1987A. They reveal cold dust grains at about –250ºC, emitting more than 200 times the Sun’s energy.
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26 July 2011
ESA’s Herschel space observatory has shown that water expelled from the moon Enceladus forms a giant torus of water vapour around Saturn. The discovery solves a 14-year mystery by identifying the source of the water in Saturn’s upper atmosphere.
Herschel’s latest results mean that Enceladus is the only moon in the Solar System known to influence the chemical composition of its parent planet.
Enceladus expels around 250 kg of water vapour every second, through a collection of jets from the south polar region known as the Tiger Stripes because of their distinctive surface markings.
These crucial observations reveal that the water creates a doughnut-shaped torus of vapour surrounding the ringed planet.
The total width of the torus is more than 10 times the radius of Saturn, yet it is only about one Saturn radius thick. Enceladus orbits the planet at a distance of about four Saturn radii, replenishing the torus with its jets of water.
Despite its enormous size, it has escaped detection until now because water vapour is transparent to visible light but not at the infrared wavelengths Herschel was designed to see.
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“ESA’s Infrared Space Observatory found the water vapour in Saturn’s atmosphere. Then NASA/ESA’s Cassini/Huygens mission found the jets of Enceladus. Now Herschel has shown how to fit all these observations together.”
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Herschel uncovers 'hidden' oxygen in Orion
01 Aug 2011
Herschel has found the first robust evidence of molecular oxygen in the Orion Nebula. The observed abundance is ten times larger than indicated by previous observations of other molecular clouds, but is still well below theoretical expectations. The results suggest that, in special circumstances, the heat from newborn stars can liberate oxygen frozen out on dust grains, thus increasing the amount of molecular oxygen able to form in warm, dense gas clouds.
Comet Hartley 2 contains water more like that found on Earth than prior comets seem to have, researchers say.
A study using the Herschel space telescope aimed to measure the quantity of deuterium, a rare type of hydrogen, present in the comet's water.
Like our oceans, it had half the amount of deuterium seen in other comets.
http://www.bbc.co.uk/news/science-environment-12065464One of Europe's great astronomical ventures is coming to a close.
The Planck telescope, put in space to map the oldest light in the Universe, has run out of the helium coolant that keeps it in full working order.
16 January 2012
The High Frequency Instrument on ESA's Planck mission has completed its survey of the remnant light from the Big Bang. The sensor ran out of coolant on Saturday as expected, ending its ability to detect this faint energy.
"Planck has been a wonderful mission; spacecraft and instruments have been performing outstandingly well, creating a treasure trove of scientific data for us to work with," said Jan Tauber, ESA's Planck Project Scientist.
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Herschel, Europe's billion-euro space observatory, has entered what is likely to be its last year of operation.
The telescope studies the formation of stars, and has taken some remarkable pictures since its launch in May 2009.
But its detectors require a constant supply of superfluid helium to keep working, and the store of this coolant has now dropped to less than 100kg.
This past week saw Herschel begin what engineers believe will be the final 365 days of its mission life.
The European Space Agency's Herschel space telescope, due to end its mission observing the infrared universe in March, may be sent on a crashing course toward the moon next summer to search for water embedded beneath the lunar surface, according to scientists.
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Two options are under serious consideration by ESA managers:
Place Herschel into a solar orbit where it could not encounter Earth again for at least hundreds of years.
Guide Herschel on a course toward the moon for a destructive high-speed collision to search for water. It would take about 100 days for Herschel to reach the moon, depending on which pole is targeted.
Spaceflight Now: Scientists could aim derelict telescope for moon impact:
The Herschel space telescope is slated to be decommissioned next March as the observatory’s supply of cryogenic helium will be depleted. One idea for “disposing” of the spacecraft was to have it impact the Moon, a la the LCROSS mission that slammed into the Moon in 2009, and it would kick up volatiles at one of the lunar poles for observation by another spacecraft, such as the Lunar Reconnaissance Orbiter. However, that idea has been nixed in favor of parking Herschel in a heliocentric orbit.
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