Astronomy news

Space Weather

At ... NASA are closely watching the Sun as it begins to come alive. The concern is solar storms - or flares with the possibility of disrupting global communications. The Sun is waking up again, they say, and space weather is an urgent consideration as the modern world and its technology is dependant on satellites.

Black Holes and the origin of Earth and Moon June 7th ... a paper in the June issue of the Astronomical Journal was written on completion of a census of visible quasars that found 105,783 of them - in a quarter of the sky. What quasars are is not known - only that they are very luminous. One theory is that the light energy is being emitted by material fallin into black holes.

Bok Globules

At ... a Bok Globule is described as a dark cloud of dust and gas from which young stars form. They were originally discovered as dark splotches in fron of dense fields of stars and were given the title, holes in the heavens because they appeared, at first, to be holes in the stellar background.

Water on Mars

At we learn that a rare Mars rock holds the clue to water on the red planet. The rock outcrop is rich in carbonite minerals - which contain carbon dioxide and form readily in the presence of water. So, if conditions allowed carbonite rock to form, that would mean there was water on Mars at some stage.

Jupiter Hit ... again ...

See as Anthony Wesley, an amateur astronomer from Australia, was looking at Jupiter and witnessed a bright flash as an object struck Jupiter and burnt up in its atmosphere. He is the same sky gazer that last year spotted a scar the size of the Pacific Ocean near Jupiter's south pole  that was later proved to be an asteroid or comet strike. Using an infra-red telescope NASA found that indeed, Jupiter had been struck, and credited Wesley.

Leaves of Grass

At ... we have a post on Walt Whitman, a poet who left in one of his collections, Leaves of Grass, a reference to a 'huge meteor succession' in extremely vivid detail that has caused people to think he witnessed the event. Scholars have debated the issue for over a hundred years, and astronomers have equally been puzzled. What exactly did he see?

Origins of Earth ... a new idea ... there is a fresh insight into the origin of planet earth, involving geochemical data. The surpising result is that earth did not fully form in the beginning - but was 40 per cent of itself. See the link for details.

Huge Flare

At ... XMM Newton images of the emisson of the neutral iron flourescent line in molecular clouds around Sgr A taken between 2004 and 2008 shows that the supermassive black hole thought to be at the centre of the Milky Way went through a turbulent phase during the past few centuries. The evidence comes from surrounding molecular clouds whose variation in X-ray and gamma-ray luminosity reflects a major flare in the recent past (see the Astrophysical Journal).

Martian Ice Cap data from NASAs Mars Reconnaissance Orbiter have provided evidence of a large chasm and a series of spiral troughs on the northern ice cap of Mars (see also Nature May 27th and NASA newsletter May 26th at info [at] jpl [dot] nasa [dot] gov ). The Shallow Radar instrument onboard is sending back detailed information and it seems the northern ice cap is a stack of ice and dust layers up to 2 miles deep covering an area roughly the size of Texas.

Drought, Lightning, and the Sun ...

At tree rings have been used to compile a temperature proxy over 1000 years in NW Africa (Morocco, Algeria and Tunisia) and they show dry periods of climate in the 13th and 16th centuries - also in the late 20th century. They appear to coincide with warmish weather in northern Europe - droughts are virtually absent after around AD1500 - for about 400 years