— NASA's Hubble confirms that galaxies are the ultimate recyclers — New observations by NASA's Hubble Space Telescope are expanding astronomers' understanding of the ways in which galaxies continuously recycle immense volumes of hydrogen gas and heavy…
— Frozen comet had a watery past, University of Arizona scientists find — For the first time, scientists have found convincing evidence for the presence of liquid water in a comet, shattering the current paradigm that comets never get warm enough to melt…
— Sugar-grain sized meteorites rocked the climates of early Earth and Mars — Bombardments of 'micro-meteorites' on Earth and Mars four billion years ago may have caused the planets' climates to cool dramatically, hampering their ability to support life, according…
— Astrophysicist: White dwarfs could be fertile ground for other Earths — Planet hunters have found hundreds of planets outside the solar system in the last decade, though it is unclear whether even one might be habitable. But it could be that the best place…
— Integral spots matter a millisecond from doom — ESA's Integral gamma-ray observatory has spotted extremely hot matter just a millisecond before it plunges into the oblivion of a black hole. But is it really doomed? These unique observations…
— MESSENGER spacecraft to swing into orbit around Mercury — At 8:45 p.m. EDT on March 17, the MESSENGER spacecraft will execute a 15-minute manoeuvre that will place it into orbit around Mercury, making it the first craft ever to do so, and…
— Baby stars born to 'napping' parents — Cardiff University astronomers believe that a young star's long 'napping' could trigger the formation of a second generation of smaller stars and planets orbiting around it…
— Oldest objects in solar system indicate a turbulent beginning — Scientists have found that calcium, aluminium-rich inclusions (CAIs), some of the oldest objects in the solar system, formed far away from our sun and then later fell back into the…
— Oxygen isotope analysis tells of the wandering life of a dust grain 4.5 billion years ago — Scientists have performed a micro-probe analysis of the core and outer layers of a pea-sized piece of a meteorite some 4.57 billion years old to reconstruct the history of its formation,…
Mercury featured in colour!
One week ago, NASA's MESSENGER spacecraft transmitted to Earth the first high-resolution image of Mercury by a spacecraft in over 30 years, since the three Mercury flybys of Mariner 10 in 1974 and 1975.
MESSENGER's Wide Angle Camera (WAC), part of the Mercury Dual Imaging System (MDIS), is equipped with 11 narrow-band colour filters, in contrast to the two visible-light filters and one ultraviolet filter that were on Mariner 10's vidicon camera.
By combining images taken through different filters in the visible and infrared, the MESSENGER data allow Mercury to be seen in a variety of high-resolution colour views not previously possible. MESSENGER's eyes can see far beyond the colour range of the human eye, and the colours seen in the accompanying image are somewhat different from what a human would see.
The colour image was generated by combining three separate images taken through WAC filters sensitive to light in different wavelengths; filters that transmit light with wavelengths of 1000, 700, and 430 nanometres (infrared, far red, and violet, respectively) were placed in the red, green, and blue channels, respectively, to create this image.
The human eye is sensitive across only the wavelength range 400 to 700 nanometres. Creating a false-colour image in this way accentuates colour differences on Mercury's surface that cannot be seen in the single-filter, black-and-white images released last week.
This visible-infrared image shows an incoming view of Mercury, about 80 minutes before MESSENGER's closest pass of the planet on Jan. 14, 2008, from a distance of about 27,000 kilometres (17,000 miles).
Image sequences acquired through the 11 different MDIS filters are being used to distinguish subtle colour variations indicative of different rock types. By analysing colour differences across all 11 filters, the MESSENGER team is investigating the variety of mineral and rock types present on Mercury's surface. Such information will be key to addressing fundamental questions about how Mercury formed and evolved.
Mercury has a diameter of about 4,880 kilometres (3,030 miles), and the smallest feature visible in the colour image is about 10 kilometres (6 miles) in size.
Or subscribe for our Newsletter, a free e-mail publication. It is published practically every day.
Kepler detects atmosphere of giant gas exoplanet
Double engine for a nebula
Hubble captures the recent impact on Jupiter
Spitzer images out-of-this-world galaxy