Wednesday, September 12, 2018

Staring Down Hurricane Florence

"Ever stared down the gaping eye of a category 4 hurricane? It's chilling, even from space," says European Space Agency astronaut Alexander Gerst(@Astro_Alex), who is currently living and working aboard the International Space Station as a member of the Expedition 56 crew.

A high-definition video camera outside the space station captured stark and sobering views of Hurricane Florence, a Category 4 storm. The video was taken on Tuesday as Florence churned across the Atlantic in a west-northwesterly direction with winds of 130 miles per hour. The National Hurricane Center forecasts additional strengthening for Florence before it reaches the coastline of North Carolina and South Carolina early Friday, Sept. 14.

Get the latest NASA information on the hurricane.

Image Credit: ESA/NASA–A. Gerst

International Space Station

Tuesday, September 11, 2018

Bright Spots On Ceres

Bright surface features on the dwarf planet Ceres known as faculae were first discovered by NASA'sDawn spacecraft in 2015. This mosaic of one such feature, Cerealia Facula, combines images obtained from altitudes as low as 22 miles (35 km) above Ceres' surface. The mosaic is overlain on a topography model based on images obtained during Dawn's low altitude mapping orbit (240 miles or 385 km altitude). No vertical exaggeration was applied. The center of Cerealia Facula is located at 19.7 degrees north latitude and 239.6 degrees south longitude.

During its mission of over a decade, the Dawn spacecraft has studied the asteroid Vesta and dwarf planet Ceres, celestial bodies believed to have formed early in the history of the solar system. The mission's goal is to characterize the early solar system and the processes that dominated its formation.

Image Credit: NASA


Friday, September 7, 2018

Aurora around Saturn's North Pole

Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraftmonitored Saturn's North Pole simultaneously during Cassini's final orbits around the gas giant in September 2017. During this time,Saturn's tilt caused its North Pole to beclearly visible from Earth. The featured image is a composite of ultraviolet images of aurora and optical images of Saturn's clouds and rings, all taken recently by Hubble. Like on Earth, Saturn's northern auroras can maketotal or partial rings around the pole. Unlike on Earth, however, Saturn's auroras are frequently spirals -- and more likely to peak in brightness just before midnight and dawn. In contrast to Jupiter's aurorasSaturn's aurorasappear better related to connecting Saturn's internal magnetic field to the nearby, variable, solar windSaturn's southern auroras were similarly imaged back in 2004 when the planet's South Pole was clearly visible to Earth.
Image CreditNASAESAHubbleOPAL ProgramJ. DePasquale (STScI), L. Lamy (Obs. Paris)

Hubble Space Telescope

Hubble’s Lucky Observation of an Enigmatic Cloud

The little-known nebula IRAS 05437+2502 billows out among the bright stars and dark dust clouds that surround it in this striking image from the Hubble Space Telescope. It is located in the constellation of Taurus (the Bull), close to the central plane of our Milky Way galaxy. Unlike many of Hubble’s targets, this object has not been studied in detail and its exact nature is unclear. At first glance it appears to be a small, rather isolated region of star formation, and one might assume that the effects of fierce ultraviolet radiation from bright, young stars probably were the cause of the eye-catching shapes of the gas. However, the bright, boomerang-shaped feature may tell a more dramatic tale. The interaction of a high-velocity young star with the cloud of gas and dust may have created this unusually sharp-edged, bright arc. Such a reckless star would have been ejected from the distant young cluster where it was born and would travel at 200,000 kilometers per hour (124,000 miles per hour) or more through the nebula.

This faint cloud was originally discovered in 1983 by the Infrared Astronomical Satellite (IRAS), the first space telescope to survey the whole sky in infrared light. IRAS was run by the United States, the Netherlands, and the United Kingdom and found huge numbers of new objects that were invisible from the ground.

This image was taken with the Wide Field Channel of the Advanced Camera for Surveys on Hubble. It was part of a 'snapshot' survey. These are observations that are fitted into Hubble’s busy schedule when possible, without any guarantee that the observation will take place — so it was fortunate that the observation was made at all. This picture was created from images taken through yellow and near-infrared filters.

Credit: ESA/Hubble, R. Sahai and NASA
Text Credit: European Space Agency (ESA)

Hubble Space Telescope

Saturn's North Polar Hexagon

In full view, the amazing six-sided jet stream known as Saturn's north polar hexagon is shown in this colorful Cassini image. Extending to 70 degrees north latitude, the false-color video frame is map-projected, based on infrared, visible, and ultraviolet image data recorded by the Saturn-orbiting spacecraft in late 2012. First found in the outbound Voyager flyby images from the 1980s, the bizarre, long-lived feature tied to the planet's rotation is about 30,000 kilometers across. At its center lies the ringed gas giant's hurricane-like north polar storm. A new long term study of Cassini data has found a remarkable higher-altitude vortex, exactly matching the outlines of the north polar hexagon, that formed as summer approached the planet's northern hemisphere. It appears to reach hundreds of kilometers above these deeper cloud tops, into Saturn's stratosphere.

Image Copyright: Image Credit: NASA,JPL-CaltechSpace Science Institute,Hampton University


Friday, August 31, 2018

Clone Mars

Still bright in evening skies, Mars was just past opposition and closest to Earth on July 31, a mere 57.6 million kilometers away. Captured only a week later, this remarkable image shows theRed Planet's disk near its maximum size in earthbound telescopes, but still less than 1/74th the apparent diameter of a Full Moon. Broad regional surface shadings are starting to reappear in thetantalizing view as the latest planet-wide dust storm subsides. With the bright south polar cap at the bottom, the Valles Marineris extends along the center of the disk. Just below it lies the roughly circular Solis Lacus region sometimes known as the Eye of Mars. In a line, three prominent dark spots left of center are the volcanic Tharsis Montes.

Image Copyright: D. Peach

Hubble Space Telescope

Wednesday, August 29, 2018

Messier 20 and 21

Messier 20 and 21

The beautiful Trifid Nebula, also known as Messier 20, is easy to find with a small telescope in the nebula rich constellation Sagittarius. About 5,000 light-years away, the colorful study incosmic contrasts shares this well-composed, nearly 1 degree wide field with open star cluster Messier 21(bottom right). Trisected by dust lanes the Trifid itself is about 40 light-years across and a mere 300,000 years old. That makes it one of the youngest star forming regions in our sky, with newborn and embryonic stars embedded in its natal dust and gas clouds. Estimates of the distance to open star cluster M21 are similar to M20's, but though they share this gorgeous telescopic skyscape there is no apparent connection between the two. In fact, M21's stars are much older, about 8 million years old.

Image Copyright: Ignacio Diaz Bobillo