Astronomy Picture Of the Day (APOD)NGC 3314: When Galaxies Overlap
Can this be a spiral galaxy? In fact, NGC 3314 consists of two large spiral galaxies which just happen to almost exactly line-up. The foreground spiral is viewed nearly face-on, its pinwheel shape defined by young bright star clusters.
Dog-Bone Shaped Asteroid 216 Kleopatra
An asteroid the size of New Jersey that orbits the Sun between Mars and Jupiter has been discovered to have an unusual dog-bone shape. Asteroid 216 Kleopatra, recently mapped with Earth-based radar, reflects radio waves so well that astronomers speculate it is composed mostly of metals such as nickel and iron.
The Race to Reveal Our Universe
A race is underway to understand our universe through background radiation produced during its infancy. Observationally, increasingly accurate balloon experiments are pressing to beat future space-faring satellites to definitive measurements of universe-determining spot characteristics of the cosmic microwave background (CMB) radiation.
Jupiters Moons Thebe, Amalthea, and Metis
The robot spacecraft Galileo in orbit around Jupiter has recently photographed the inner moons of Jupiter in greater detail than ever before. These pictures of Thebe, Amalthea, and Metis are shown to scale, and reveal details as small as three kilometers across. Amalthea, by contrast, has a total length of about 200 kilometers.
A Green Flash from the Sun
Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood.
The Heart Of Orion
Newborn stars lie at at the heart of the the Orion Nebula, hidden from view by the dust and gas of the giant Orion Molecular Cloud number 1 (OMC-1). Sensitive to invisible infrared...
Planets In The Sun
Today, all five naked-eye planets (Mercury, Venus, Mars, Jupiter, Saturn) plus the Moon and the Sun will at least approximately line-up. As viewed from planet Earth, they will be clustered within about 26 degrees, the closest alignment for all these celestial bodies since February 1962, when there was a solar eclipse!
Planets Above The Clouds
Clouds scatter the faint orange rays of the setting sun in the foreground of this breathtaking photograph from the summit of Mauna Kea, Hawaii. Taken on April 7th, this skyscape features a dramatic lunar and planetary alignment.
BOOMERANG Images The Early Universe
Drifting through the stratosphere above Antarctica in late 1998, the balloon-borne BOOMERANG telescope peered into the cosmos at millimeter wavelengths. The blotchy structures it detected are seen above in the sharpest yet picture of the universe at an early age, perhaps a mere 300,000 years old.
An Iridium Flash Sunset
Did you see that flash? Lasting only about 15 seconds, it's possible that nobody you ask can confirm it, but what you might have seen is sunlight reflecting off an orbiting Iridium satellite. Satellites of all types have been providing streaks and glints visible only since the launch of Sputnik I in 1957.