Seen edge-on, spiral galaxy NGC 4302 (left) lies about 55 million light-years away in the well-groomed constellation Coma Berenices. A member of the large Virgo Galaxy Cluster, it spans some 87,000 light-years, a little smaller than our own Milky Way. Like the Milky Way, NGC 4302’s prominent dust lanes cut along the center of the galactic plane, obscuring and reddening the starlight from our perspective. Smaller companion galaxy NGC 4298 is also a dusty spiral. But tilted more nearly face-on to our view, NGC 4298 can show off dust lanes along spiral arms traced by the bluish light of young stars, as well as its bright yellowish core. In celebration of the 27th anniversary of the launch of the Hubble Space Telescope on April 24, 1990, astronomers used the legendary telescope to take this gorgeous visible light portrait of the contrasting galaxy pair.
No planet is better studied than the one we actually live on. NASA’s fleet of 18 Earth science missions in space, supported by aircraft, ships and ground observations, measure aspects of the environment that touch the lives of every person around the world. They study everything from the air we breathe, to rain and snow that provide water for agriculture and communities, to natural disasters such as droughts and floods, to the oceans, which cover 70 percent of Earth’s surface and provide food for many people around the world. Satellites and instruments on the International Space Station circle the whole globe, seeing both where people live and those remote parts of deserts, mountains and the vast oceans that are difficult if not impossible to visit. With instruments in space, scientists can get data for the whole globe in detail that they can’t get anywhere else. This visualization shows the NASA fleet in 2017, from low Earth orbit all the way out to the DSCOVR satellite taking in the million-mile view.
The Soyuz MS-04 rocket launches from the Baikonur Cosmodrome in Kazakhstan on Thursday, April 20, 2017 at 1:13 p.m. Baikonur time carrying NASA astronaut Jack Fischer and cosmonaut Fyodor Yurchikhin of the Russian space agency Roscosmos into orbit to begin their four and a half month mission on the International Space Station.
After a six-hour flight, their Soyuz arrived at the International Space Station at 9:18 a.m. EDT Thursday, where the two new crew members joined Expedition 51 Commander Peggy Whitson of NASA and Flight Engineers Oleg Novitskiy of Roscosmos and Thomas Pesquet of ESA (European Space Agency). The Expedition 51 crew members will conduct approximately 250 science investigations in fields such as biology, Earth science, human research, physical sciences and technology development.
A day before its closest approach, asteroid 2014 JO25 was imaged by radar with the 70-meter antenna of NASA’s Goldstone Deep Space Communications Complex in California. This grid of 30 radar images, top left to lower right, reveals the two-lobed shape of the asteroid that rotates about once every five hours. Its largest lobe is about 610 meters across. On the list of Potentially Hazardous Asteroids, this space rock made its close approach to our fair planet on April 19, flying safely past at a distance of 1.8 million kilometers. That’s over four times the distance from the Earth to the Moon. The asteroid was a faint and fast moving speck visible in backyard telescopes. Asteroid 2014 JO25 was discovered in May 2014 by the Catalina Sky Survey, a project of NASA’s Near-Earth Objects Observations Program in collaboration with the University of Arizona.
Oh what a tangled web a planetary nebula can weave. The Red Spider Planetary Nebula shows the complex structure that can result when a normal star ejects its outer gases and becomes a white dwarf star. Officially tagged NGC 6537, this two-lobed symmetric planetary nebula houses one of the hottest white dwarfs ever observed, probably as part of a binary star system. Internal winds emanating from the central stars, visible in the center, have been measured in excess of 1000 kilometers per second. These winds expand the nebula, flow along the nebula’s walls, and cause waves of hot gas and dust to collide. Atoms caught in these colliding shocks radiate light shown in the above representative-color picture by the Hubble Space Telescope. The Red Spider Nebula lies toward the constellation of the Archer (Sagittarius). Its distance is not well known but has been estimated by some to be about 4,000 light-years.
At the center of the Centaurus galaxy cluster, there is a large elliptical galaxy called NGC 4696. Deeper still, there is a supermassive black hole buried within the core of this galaxy.
New data from NASA’s Chandra X-ray Observatory and other telescopes has revealed details about this giant black hole, located some 145 million light years from Earth. Although the black hole itself is undetected, astronomers are learning about the impact it has on the galaxy it inhabits and the larger cluster around it.
In some ways, this black hole resembles a beating heart that pumps blood outward into the body via the arteries. Likewise, a black hole can inject material and energy into its host galaxy and beyond.
By examining the details of the X-ray data from Chandra, scientists have found evidence for repeated bursts of energetic particles in jets generated by the supermassive black hole at the center of NGC 4696. These bursts create vast cavities in the hot gas that fills the space between the galaxies in the cluster. The bursts also create shock waves, akin to sonic booms produced by high-speed airplanes, which travel tens of thousands of light years across the cluster.
This composite image contains X-ray data from Chandra (red) that reveals the hot gas in the cluster, and radio data from the NSF’s Karl G. Jansky Very Large Array (blue) that shows high-energy particles produced by the black hole-powered jets. Visible light data from the Hubble Space Telescope (green) show galaxies in the cluster as well as galaxies and stars outside the cluster.
Astronomers employed special processing to the X-ray data to emphasize nine cavities visible in the hot gas. These cavities are labeled A through I in an additional image, and the location of the black hole is labeled with a cross. The cavities that formed most recently are located nearest to the black hole, in particular the ones labeled A and B.
The researchers estimate that these black hole bursts, or “beats”, have occurred every five to ten million years. Besides the vastly differing time scales, these beats also differ from typical human heartbeats in not occurring at particularly regular intervals.
A different type of processing of the X-ray data reveals a sequence of curved and approximately equally spaced features in the hot gas. These may be caused by sound waves generated by the black hole’s repeated bursts. In a galaxy cluster, the hot gas that fills the cluster enables sound waves – albeit at frequencies far too low for the human hear to detect – to propagate.
The features in the Centaurus Cluster are similar to the ripples seen in the Perseus cluster of galaxies. The pitch of the sound in Centaurus is extremely deep, corresponding to a discordant sound about 56 octaves below the notes near middle C. This corresponds to a slightly higher (by about one octave) pitch than the sound in Perseus. Alternative explanations for these curved features include the effects of turbulence or magnetic fields.
The black hole bursts also appear to have lifted up gas that has been enriched in elements generated in supernova explosions. The authors of the study of the Centaurus cluster created a map showing the density of elements heavier than hydrogen and helium. The brighter colors in the map show regions with the highest density of heavy elements and the darker colors show regions with a lower density of heavy elements. Therefore, regions with the highest density of heavy elements are located to the right of the black hole. A lower density of heavy elements near the black hole is consistent with the idea that enriched gas has been lifted out of the cluster’s center by bursting activity associated with the black hole. The energy produced by the black hole is also able to prevent the huge reservoir of hot gas from cooling. This has prevented large numbers of stars from forming in the gas.
A paper describing these results was published in the March 21st 2016 issue of the Monthly Notices of the Royal Astronomical Society and is available online. The first author is Jeremy Sanders from the Max Planck Institute for Extraterrestrial Physics in Garching, Germany.
The Orbital ATK Cygnus pressurized cargo module is carried atop the United Launch Alliance Atlas V rocket as it launches from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. Orbital ATK’s seventh commercial resupply services mission, CRS-7, will deliver 7,600 pounds of supplies, equipment and scientific research materials to the International Space Station. Liftoff was at 11:11 a.m. EDT on Tuesday, April 18, 2017. At about 6:05 a.m. EDT on Saturday, April 22, Expedition 51 astronauts Thomas Pesquet of ESA (European Space Agency) and Peggy Whitson of NASA will use the space station’s robotic arm to grapple Cygnus, which will be installed on the Unity module.
Image Credit & Copyright: Taha Ghouchkanlu
What glows in the night? This night, several unusual glows were evident — some near, but some far. The foreground surf glimmers blue with the light of bioluminescent plankton. Next out, Earth’s atmosphere dims the horizon and provides a few opaque clouds. Farther out, the planet Venus glows bright near the image center. If you slightly avert your eyes, a diagonal beam of light will stand out crossing behind Venus. This band is zodiacal light, sunlight scattered by dust in our Solar System. Much farther away are numerous single bright stars, most closer than 100 light years away. Farthest away, also rising diagonally and making a “V” with the zodiacal light, is the central band of our Milky Way Galaxy. Most of the billions of Milky Way stars and dark clouds are thousands of light years away. The featured image was taken last November on the Iranian coast of Gulf of Oman.
When imaged at infrared wavelengths that pierce the planet’s upper haze layer, the high-speed winds of Saturn’s atmosphere produce watercolor-like patterns.
With no solid surface creating atmospheric drag, winds on Saturn can reach speeds of more than 1,100 miles per hour (1,800 kilometers per hour) — some of the fastest in the solar system.
This view was taken from a vantage point about 28 degrees above Saturn’s equator. The image was taken with the Cassini spacecraft wide-angle camera on Dec. 2, 2016, with a combination of spectral filters which preferentially admits wavelengths of near-infrared light centered at 728 nanometers.
The view was acquired at a distance of approximately 592,000 miles (953,000 kilometers) from Saturn. Image scale is 35 miles (57 kilometers) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.
For more information about the Cassini-Huygens mission visit https://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org .
Credit: NASA/JPL-Caltech/Space Science Institute