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What Venus Express learned by aerobraking

Venus Express aerobraking. Image credit: ESA - C. Carreau

Venus Express aerobraking. Image credit: ESA – C. Carreau

ESA has announced some final results sent back by Venus Express obtained when – in the spacecraft’s final months – it surfed in Venus’ dense atmosphere. The data show the planet’s atmosphere to be rippling with atmospheric waves and colder than anywhere on Earth.

Moon rocks reveal nearby supernova

Moon rocks collected b Apollo astronauts have been found to contain an element created only by supernovae. Here, Apollo 12-astronaut Alan Bean takes a sample of the lunar surface. Photo via NASA.

Moon rocks collected by Apollo astronauts have been found to contain iron-60, which is created only by supernovae. Here, Apollo 12-astronaut Alan Bean takes a sample of the lunar surface. Photo via NASA.

Scientists have discovered iron-60, a form of iron only created in supernovae, in moon rocks collected by Apollo astronauts. It supports an earlier finding that – 2 million years ago – a supernova exploded only 300 light-years away.

Comet Halley, parent of 2 meteor showers

Comet Halley's position in May, 2016. The view is from the north side of the solar system, whereby the planets orbit the sun in a counterclockwise direction - but Halley's Comet orbits the sun clockwise. Click here for Comet Halley's present position, or if you'd like, change the date to view its position in any chosen year.

Comet Halley’s position in May, 2016. The view is from the north side of the solar system. Although the planets orbit our sun in a counterclockwise direction, Comet Halley orbits clockwise.

The 2 meteor showers spawned by the famous Comet Halley. And a word about Isaac Newton’s Vis-viva equation, his poetic rendition of instantaneous motion.

Crab Nebula was an exploding star

Crab Nebula

The Crab Nebula is a cloud of gas and debris rushing outward from a great stellar explosion seen a thousand years ago by earthly skywatchers. Credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)

The Crab Nebula, located some 6,500 light years from Earth, marks the remains of a massive star observed to explode as a supernova in AD 1054.

Photos from friends: Favorite images of Earth

Kristal Alaimo-Moritz? wrote,

Kristal Alaimo-Moritz wrote, “Where would we bee without you. In honor of Earth Day 2016.” Thank you Kristal!

In celebration of Earth Day 2016, we’ve brought together some of our favorite images of Earth by the EarthSky community. Thank you all!

Mars is getting bright! Here’s why

Earth will between between the sun and Mars on May 22, 2016.  Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky.  Image via Fourmilab.

Earth will pass between between the sun and Mars on May 22, 2016. Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky. Image via Fourmilab.

We’ll pass between Mars and the sun just one month from today, on May 22. Watch Mars brighten dramatically between now and then!

10 surprises about our solar system

Montage of our solar system.  Image Credit: NASA/JPL

Artists’s concept (montage) of our solar system. Image via NASA/JPL

A collection of 10 unexpected and intriguing facts about our solar system – our sun and its family of planets – you probably did not know!

Eastern monarch butterflies at risk of extinction, scientists say

Monarch butterfly on the Sullys Hill Game Preserve, North Dakota. Image Credit: U.S. Fish and Wildlife Service.

Monarch butterfly on the Sullys Hill Game Preserve, North Dakota. Image Credit: U.S. Fish and Wildlife Service.

Populations of the charismatic orange and black monarch butterfly have plummeted. Will they be extinct in 20 years?

Green moon on April 20, 2016? Not true

This green moon photo was created via photo processing, and is via Wikimedia Commons.

This green moon photo was created via photo processing, and is via Wikimedia Commons.

There are several versions this (completely untrue) story, and we’ve gotten many questions about it from within our community, from people wanting to know if it’s true. Here’s the main version: the moon will appear green for the first time in 420 years on April 20, 2016. True? No, not even kinda.

Why are these black hole jets aligned?

Astronomers have circled galaxies in this radio image, whose central supermassive black holes have jets that are aligned.  Image via Andrew Russ Tayor

Astronomers have circled galaxies in this deep-sky radio image, whose central supermassive black holes have jets that are aligned. Image via Andrew Russ Taylor.

South African astronomers conducting a three-year survey of the distant universe at radio wavelengths have images of supermassive black hole jets in a particular region of space that are all aligned in the same direction. The only way for this alignment to exist is if the supermassive black holes in this part of space are all spinning in the same direction.