Tonight – April 21, 2015 – look westward as darkness falls for the beautiful waxing crescent moon and bright planet Venus. They will dominate the western sky shortly after the sun goes down. As night passes, and Earth spins under the sky, the moon and Venus will soon follow the sun below the western horizon, leaving the sky dark for the 2015 Lyrid meteor shower. Follow the links inside to learn more.
On Tuesday morning according to U.S. clocks – at approximately 3 a.m. CDT, or 8 UTC – a small and very faint asteroid will pass just 0.2 lunar distances or 45,600 miles (73,400 km) above Earth’s surface. That’s about twice as far as geostationary satellites. The Mt. Lemmon Survey, based in Tucson, Arizona, first saw this asteroid two days ago, on April 18.
Dawn spacecraft has reacquired images of Spot 5, the mysterious bright double feature on the dwarf planet Ceres. The bright spots look … as strange as ever.
Whales, dolphins, seals and sea turtles are members of an exceptional group of animals, called marine tetrapods, that have moved from the sea to the land and back to the sea again over the last 350 million years — each time making radical changes to their life style, body shape, physiology and sensory systems.
What made these animals return to the ocean? Neil Kelley is a researcher at the Smithsonian National Museum of Natural History’s department of paleobiology. Kelley said:
They followed their stomachs into the ocean.
That glow over the unlit part of a crescent moon – called earthshine – is light reflected from Earth.
Beautiful photos in this post!
During the Permian–Triassic mass extinction event 252 million years ago, most life on Earth perished. Scientists have now obtained evidence that ocean acidification played a key role in the die-off.
The Lyrid meteor shower is active each year from about April 16-25, and we’re now approaching the peak of this shower. The peak night for the Lyrid meteor shower will probably fall on the mornings of April 22 and 23. This modest shower often offers no more than 10 to 20 meteors per hour at its peak, but it has been known to have bursts of activity that could dazzle you. Fortunately, the waxing crescent moon will be setting at early evening, guaranteeing a dark sky for meteor watching. Watch from late night until dawn.
On April 24, 1990, the space shuttle Discovery lifted off from Earth with the Hubble Space Telescope aboard. The following day:
… Hubble was released into space, ready to peer into the vast unknown. Since then, Hubble has reinvigorated and reshaped our perception of the cosmos and uncovered a universe where almost anything seems possible within the laws of physics.
The quote above is from a NASA website where the agency explains its plans to celebrate Hubble’s 25th anniversary. The celebration begins on April 20, 2015 and runs through April 26. There are a lot of activities mentioned – plus links to more information – inside.
The Hubble Space Telescope is celebrating its 25th anniversary this week. Has any other recent innovation in astronomy so changed our perception of the cosmos? We’ll be running some glorious Hubble images this week, like the one above of ESO 510-G13, a warped spiral galaxy seen edge-on from our earthly perspective. The dust and spiral arms of normal spiral galaxies, like our own Milky Way, appear flat when viewed edge-on. This galaxy has an unusual twisted disk structure.
You might see a lot or you might not see many, but if you stay in the house, you won’t see any. Tips for getting the most from this week’s Lyrid meteor shower … or any meteor shower.