Archive – Page 317 – Astronomy Now

3× four-element Barlow lens

12 May 2015 Steve Ringwood

Steve Ringwood investigates a 4-element, 3x Barlow lens that’s designed to provide efficient field correction and apochromatic performance that can match other highly specified optics in the light path.

Powerful new radio telescope array searches the entire sky 24/7

12 May 2015 Astronomy Now

A new radio telescope array operating at the Owens Valley Radio Observatory in California has the ability to image the entire sky simultaneously at radio wavelengths with unmatched speed, helping astronomers to search for objects and phenomena that pulse, flicker, flare, or explode.

Ceres’ mysterious white spots resolved in latest Dawn images

11 May 2015 Astronomy Now

The enigmatic white features on the dwarf planet Ceres are better resolved in a new sequence of images taken by NASA’s Dawn spacecraft on May 3rd and 4th. In this closest-yet view, the brightest spots within a crater in the northern hemisphere are revealed to be composed of many smaller spots. However, their exact nature remains unknown.

Venus’ late night show in May

11 May 2015 Ade Ashford

Even casual observers cannot fail to notice dazzling Venus currently gracing the western horizon at dusk. Owing to a favourable set of circumstances, the brightest planet is visible long after sunset. How late can you see it set in the British Isles? For those north of the Arctic Circle, Venus is presently circumpolar and doesn’t set at all!

Dawn observes Ceres’ northern hemisphere

10 May 2015 Astronomy Now

On May 8th, NASA’s Dawn spacecraft completed its mapping of the northern and southern hemisphere of dwarf planet Ceres in this orbit. The craft is now using its ion thruster to spiral down to the second mapping orbit. This image comes from May 4th.

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Institute for Pale Blue Dots renamed in honour of Carl Sagan

10 May 2015 Astronomy Now

Carl Sagan’s highly inspirational 1980 TV series “Cosmos: A Personal Voyage” launched many a career in astronomy. Now the Carl Sagan Institute: Pale Blue Dot and Beyond — a research institution devoted to the pursuit of Sagan’s challenge to explore other worlds, to learn if they, too, contain life — was unveiled at Cornell University on May 9th.

MESSENGER found evidence of Mercury’s ancient magnetic field

9 May 2015 Astronomy Now

About 4 billion years ago, Mercury’s magnetic field could have been much stronger than today, as indicated by low-altitude observations made by NASA’s MESSENGER spacecraft that revealed evidence of magnetisation of the innermost planet’s ancient crustal rocks.

Lopsided star explosion holds the key to other supernova mysteries

8 May 2015 Astronomy Now

New observations of the remnant of supernova (SN) 1987A are confirming supercomputer model predictions made at Caltech that the deaths of stellar giants are lopsided affairs in which debris and the stars’ cores hurtle off in opposite directions.

Hubble finds giant halo around the Andromeda Galaxy

7 May 2015 Astronomy Now

Scientists using NASA’s Hubble Space Telescope have discovered that the immense halo of gas enveloping the Andromeda Galaxy, our nearest massive galactic neighbour, is about six times larger and 1,000 times more massive than previously measured.

Geochemical process on Saturn’s moon Enceladus linked to life’s origin

7 May 2015 Astronomy Now

Researchers have revealed the pH of water spewing from geyser-like plumes on Saturn’s moon Enceladus. Their findings are an important step toward determining whether life could exist, or could have previously existed, on the sixth planet’s sixth-largest moon.