Morning, Moon, and Mercury
26.04.2012

Last week Mercury wandered far to the west of the Sun. As the solar system's innermost planet neared its greatest elongation or greatest angle from the Sun (for this apparition about 27 degrees) it was joined by an old crescent Moon.

Advanced LIGO: Gravitational Wave Detectors Upgraded
7.02.2016

Accelerate a charge and you'll get electromagnetic radiation: light. But accelerate any mass and you'll get gravitational radiation. Light is seen all the time, but, so far, a confirmed direct detection of gravitational radiation has been elusive.

The Fornax Cluster of Galaxies
11.06.2016

Named for the southern constellation toward which most of its galaxies can be found, the Fornax Cluster is one of the closest clusters of galaxies. About 62 million light-years away, it is almost...

The Hill, The Moon, and Saturn
16.11.2018

Last Sunday when the Moon was young its sunlit crescent hung low near the western horizon at sunset. With strong earthshine it was joined by Saturn shining in the early evening sky for a beautiful conjunction visible to skygazers around our fair planet.

The 100 Meter Green Bank Radio Telescope
11.03.2002

The largest single-dish fully steerable radio telescope began operation in 2000 August in Green Bank, West Virginia, USA. Dedicated as the Robert C. Byrd Green Bank Telescope, the device weighs over 30 times more than the Statue of Liberty, and yet can point anywhere in the sky more precisely than one thousandth of a degree.

Microlensing of the Einstein Cross
11.07.1995

The famous "Einstein Cross" is a case where a single object is seen four times. Here a very distant QSO happened to be placed right behind a massive galaxy. The gravitational effect...

The View from Husband Hill on Mars
7.09.2005

Scroll right to see a breathtaking panorama of Mars from the top of Husband Hill. The image was taken by the robotic rover Spirit now exploring the red planet. Spirit, situated in expansive Gusev Crater, has been exploring the Columbia Hills for some time including climbing Husband Hill over the last few months.

A Skygazers Full Moon
13.01.2000

This dramatically sharp picture of the full moon was recorded on 22 December, 1999 by astroimager Rob Gendler. Big, beautiful, bright, and evocative, it was the last full moon of the Y1.9Ks, pleasing and inspiring even casual skygazers.

Follow The Spots
21.10.1999

The Sun rotates on its axis about once every 27 days. How can you tell? Just follow the sunspots. This composite picture was constructed from solar images recorded daily by the MDI instrument on board the space-based SOlar and Heliospheric Observatory (SOHO).

The Milky Way Over Paranal
23.01.2007

It's not the sky that's falling. More accurately, the Earth is rising. The Earth's rotation gives a continually changing view to all Earth observers, including those measuring the universe at the Paranal Observatory.