All posts by Tom

THEMIS Records Phobos


Normally the Thermal Emission Imaging System (THEMIS) camera onboard the Odyssey orbiter is pointing towards the surface of Mars. Recently researchers developed a manuver to turn the orbiter around around so that a series of scans could be made of the Martian moon Phobos and they did just that on 29 September 2017.

The top image is a visible light image, actually part of a 19 image series that were put together into an animation. You can see the animation here (opens in a new tab) and the apparent motion you see is not from the motion of Phobos, rather it’s from the progression of the camera’s pointing during the 18-second span of the observation.

In bottom image the left edge of the small moon was in darkness, and the right edge in morning sunlight. Phobos has an oblong shape with average diameter of about 14 miles (22 kilometers). The distance to Phobos from Odyssey during the observation was about 3,424 miles (5,511 kilometers).

These and possibly future observations will allow researchers to analyze the surface-temperature information from this observation and possible future THEMIS observations to learn how quickly the surface warms after sunup or cools after sundown. That could provide information about surface materials, because larger rocks heat or cool more slowly than smaller particles do. The thermal information in this image is from merging observations made in four thermal-infrared wavelength bands, centered from 11.04 microns to 14.88 microns.

Phobos has an oblong shape with average diameter of about 14 miles (22 kilometers). Odyssey orbits Mars at an altitude of about 250 miles (400 kilometers), much closer to the planet than to Phobos, which orbits about 3,700 miles (6,000 kilometers) above the surface of Mars. The distance to Phobos from Odyssey during this observation was about 3,424 miles (5,511 kilometers).

THEMIS was developed by and is operated by a team based at Arizona State University, Tempe. NASA’s Jet Propulsion Laboratory, Pasadena, California, manages the Mars Odyssey mission for NASA’s Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and partners in its operation. JPL is a division of Caltech in Pasadena.

Image Credit: NASA/JPL-Caltech/ASU

Io and Europa

Another really great JunoCam image; this one processed by citizen scientist Roman Tkachenko.

NASA – This color-enhanced image of Jupiter and two of its largest moons — Io and Europa — was captured by NASA’s Juno spacecraft as it performed its eighth flyby of the gas giant planet.

The image was taken on Sept. 1, 2017 at 3:14 p.m. PDT (6:14 p.m. EDT). At the time the image was taken, the spacecraft was about 17,098 miles (27,516 kilometers) from the tops of the clouds of the planet at a latitude of minus 49.372 degrees.

Closer to the planet, the Galilean moon of Io can be seen at an altitude of 298,880 miles (481,000 kilometers) and at a spatial scale of 201 miles (324 kilometers) per pixel. In the distance (to the left), another one of Jupiter’s Galilean moons, Europa, is visible at an altitude of 453,601 miles (730,000 kilometers) and at a spatial scale of 305 miles (492 kilometers) per pixel.

Image: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko

NROL-52 Launch Attempt 2

Currently (08 Oct 17 at 10:00 UT) there is no update.

Weather delay on the first try, yesterday.

SCRUBBED again. This time not for weather, but for a telemetry transmitter in the launch vehicle. I’m not so sure there wouldn’t have been a weather delay anyway and better to replace a transmitter here than have it fail on the way up.

United Launch Alliance will update the launch times.

The NROL-52 mission will mark ULA’s seventh launch of 2017 and 26th for the National Reconnaissance Office. NROL-52 will be the 74th flight of the Atlas V rocket and the seventh in the 421 configuration. — UAL

United Launch Alliance NROL- 52 Launch

SCRUBBED FOR TODAY – NEW LAUNCH DAY IS TOMORROW (24 hrs) – I’ll post the new launch time when I hear from ULA.

Update: Scrubbed due to weather, new launch time is 07:59 UT / 03:59 ET on 07 Oct (tomorrow)

Spelling this morning? I think this computer is getting tired, first “t’s” and now “c’s” don’t always register. The “t” key is especially bad. I’m not sure if I remove the key to possibly clean underneath it or not.
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An Atlas V ready to take to the sky this morning.

The launch site is Cape Canaveral Florida and lift-off is scheduled for 08:28 UT / 04:28 ET.

Replays to be posted later today so if you miss/missed the live launch the replay will be here.

Night time launches are always pretty spectacular.

Currently we are getting final approvals to continue count – there is a slight delay, but only a few minutes.

Here we go, countdown is about to pick back up for a 08:31 UT / 04:31 ET launch.

Oh no, a HOLD at T-minus 01:38, weather possibly.

Rolling the count back to the T-minus four minutes.

Space Walk Coverage – REPLAY

Randy Bresnik and Mark Vande Hei spacewalk outside International Space Station. During today’s spacewalk with a goal of replacing one of two Latching End Effectors (LEE) on the station’s robotic arm, Canadarm2.

REPLAY:

The EVA is scheduled to begin at 12:00 UTC / 08:00 ET. I will take the live feed down after the EVA and possibly replace it with a condensed replay – if all goes as I expect on this end that is.

Tabby’s Star

Spitzer, Swift and AstroLAB are now involved in observing this very strange star and now maybe we are getting some answers:

Goddard/NASA – This illustration depicts a hypothetical uneven ring of dust orbiting KIC 8462852, also known as Boyajian’s Star or Tabby’s Star. Astronomers have found the dimming of the star over long periods appears to be weaker at longer infrared wavelengths of light and stronger at shorter ultraviolet wavelengths. Such reddening is characteristic of dust particles and inconsistent with more fanciful “alien megastructure” concepts, which would evenly dim all wavelengths of light.

By studying observations from NASA’s Spitzer and Swift telescopes, as well as the Belgian AstroLAB IRIS observatory, the researchers have been able to better constrain the size of the dust particles. This places them within the range found in dust disks orbiting stars, and larger than the particles typically found in interstellar dust.

The system is portrayed with a couple of comets, consistent with previous studies that have found evidence for cometary activity within the system.

Wait. . . hold on, alien megastuctures?

Well sort of, here watch this TED Talk by none other than astronomer Tabetha Boyajian:

Hubble and the Coma Cluster

A terrific look at the Coma Cluster, NGC 4874 thanks to Hubble.

ESA/Hubble & NASA — In the center of a rich cluster of galaxies located in the direction of the constellation of Coma Berenices, lies a galaxy surrounded by a swarm of star clusters. NGC 4874 is a giant elliptical galaxy, about ten times larger than the Milky Way, at the center of the Coma Galaxy Cluster. With its strong gravitational pull, it is able to hold onto more than 30,000 globular clusters of stars, more than any other galaxy that we know of, and even has a few dwarf galaxies in its grasp.

In this NASA/ESA Hubble Space Telescope image, NGC 4874 is the brightest object, located to the right of the frame and seen as a bright star-like core surrounded by a hazy halo. A few of the other galaxies of the cluster are also visible, looking like flying saucers dancing around NGC 4874. But the really remarkable feature of this image is the point-like objects around NGC 4874, revealed on a closer look: almost all of them are clusters of stars that belong to the galaxy. Each of these globular star clusters contains many hundreds of thousands of stars.

Recently, astronomers discovered that a few of these point-like objects are not star clusters but ultra-compact dwarf galaxies, also under the gravitational influence of NGC 4874. Being only about 200 light-years across and mostly made up of old stars, these galaxies resemble brighter and larger versions of globular clusters. They are thought to be the cores of small elliptical galaxies that, due to the violent interactions with other galaxies in the cluster, lost their gas and surrounding stars.

This Hubble image also shows many more distant galaxies that do not belong to the cluster, seen as small smudges in the background. While the galaxies in the Coma Cluster are located about 350 million light-years away, these other objects are much farther out. Their light took several hundred million to billions of years to reach us.

This picture was created from optical and near-infrared exposures taken with the Wide Field Channel of Hubble’s Advanced Camera for Surveys. The field of view is 3.3 arcminutes across.

Hubble Spots Comet C/2017 K2

An inbound comet and a record breaker, comet C/2017 K2 PANSTARRS (K2) is still a LONG ways out, perihelion in 2022.

More about C/2017 K2 PANSTARRS (K2).

Thanks to NASA, ESA, and D. Jewitt (UCLA):

A solitary frozen traveler has been journeying for millions of years toward the heart of our planetary system. The wayward vagabond, a city-sized snowball of ice and dust called a comet, was gravitationally kicked out of the Oort Cloud, its frigid home at the outskirts of the solar system. This region is a vast comet storehouse, composed of icy leftover building blocks from the construction of the planets 4.6 billion years ago.

The comet is so small, faint, and far away that it eluded detection. Finally, in May 2017, astronomers using the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in Hawaii spotted the solitary intruder at a whopping 1.5 billion miles away – between the orbits of Saturn and Uranus. The Hubble Space Telescope was enlisted to take close-up views of the comet, called C/2017 K2 PANSTARRS (K2).

The comet is record-breaking because it is already becoming active under the feeble glow of the distant Sun. Astronomers have never seen an active inbound comet this far out, where sunlight is merely 1/225th its brightness as seen from Earth. Temperatures, correspondingly, are at a minus 440 degrees Fahrenheit. Even at such bone-chilling temperatures, a mix of ancient ices on the surface – oxygen, nitrogen, carbon dioxide, and carbon monoxide – is beginning to sublimate and shed as dust. This material balloons into a vast 80,000-mile-wide halo of dust, called a coma, enveloping the solid nucleus.

Astronomers will continue to study K2 as it travels into the inner solar system, making its closest approach to the Sun in 2022.

Martian Aurora

The MAVEN spacecraft returned this ultraviolet spectroscopic data from Mars after the effects of a solar storm arrive.

NASA/Univ. of Colorado: These images show the sudden appearance of a bright aurora on Mars during a solar storm in September 2017. The purple-white color scheme shows the intensity of ultraviolet light seen on Mars’ night side before (left) and during (right) the event.

A simulated image of Mars for the same time and orientation has been added, with the dayside crescent visible on the right. The auroral emission appears brightest at the edges of the planet where the line of sight passes along the length of the glowing atmosphere layer.

The data are from observations by the Imaging Ultraviolet Spectrograph instrument (IUVS) on NASA’s Mars Atmosphere and Volatile Evolution orbiter, or MAVEN.

Note that, unlike auroras on Earth, the Martian aurora is not concentrated at the planet’s polar regions. This is because Mars has no strong magnetic field like Earth’s to concentrate the aurora near the poles.