NuSTAR Rides Pegasus to Orbit

“Stargazer” L-1011 Aircraft with NuSTAR Prior to Take Off – T-105 minutes
Image Credit: NASA TV / UStream

NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) spacecraft is scheduled for launch this morning 13 June 2012, after being postponed this Spring. Launch is currently scheduled for 9:00 AM Phoenix time (16:00 UTC), with a window between 8:30 AM and 12:30 PM Phoenix time (15:30-19:30 UTC). Coverage and commentary will be broadcast online beginning 90 minutes before launch at

At 7:25 AM Phoenix time, we are 1 hour and 35 minutes from launch.


NuSTAR X-RAY Observatory Set for Launch on Wednesday

Nuclear Spectroscopic Telescope Array (NuSTAR)
Image Credit: NASA / JPL-Caltech

NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) spacecraft is scheduled for launch this coming Wednesday 13 June 2012, after being postponed this Spring. Launch is scheduled for a window between 8:30 AM and 12:30 PM Phoenix time (15:30-19:30 UTV). Coverage and commentary will be broadcast online beginning 90 minutes before launch at

The launch vehicle is an Orbital Sciences Pegasus XL rocket. The Pegasus will be launched from a Lockheed L-1011, named “Stargazer” (below), flying at 40,000 feet. The aircraft has already moved from Vandenberg Air Force base to the Reagan Test Site on the Kwajalein Atoll in the Marshall Islands. The “Stargazer”, Pegasus and NuSTAR will take off and fly to 40,000 feet. Five seconds after drop the Pegasus will ignite and put NuSTAR into a low Earth orbit

Stargazer with Pegasus XL Landing on the Kwajalein Atoll
Image Credit: Orbital Sciences

Check out the NASA Press Release about the NuSTAR mission.

The short summary:

  • First observatory to focus high energy X-rays
  • 10 times the resolution and 100 times the sensitivity of previous spacecraft
  • Coordinate observations with Chandra X-ray Observatory
  • Use new mirror and detector technology that was developed in NASA’s basic research program
  • Study large and small black holes, near and far
  • Focus high energy X-rays images (see below)
  • Use nested shell mirrors with 133 in each of two optic units
  • Use state of the art detectors and a 10-meter mast that connects the detectors to the nested mirrors

Illustration of the Focusing Power of the NuSTAR X-Ray Observatory
Image Credit: ESA / NASA / JPL-Caltech

Older observations on the upper left versus NuSTAR resolution in the lower right.

Kepler Mission Extension

2321 Planets
2321 Potential Planet Discoveries by Kepler Space Observatory
Image Credit: NASA Ames / Wendy Stenzel

The Kepler mission, discoverer of 2,321 possible planets around stars in the region near Cygnus (star map) in our Milky Way galaxy, has been extended through 2016 based on a recommendation from the Agency’s Senior Review (pdf document)

Also, Kepler has discovered 2,165 eclipsing binary stars. Binary stars for when most of the mass of the solar system ring condenses or accretes into a single body with enough mass to ignite a fusion reaction, rather than several Jupiter and Neptune sized objects with some rocky planets.

The Kepler Mission has a Quick Guide, which explains the workings of the observatory.

Kepler Systems
Multi-Planet Systems Discovered by the Kepler Space Observatory (not to scale)
Image Credit: NASA Ames / Dan Fabrycky, UC Santa Cruz

The above diagram illustrates the multi-planet systems found by Kepler. The maps represent the relative sizes of the systems and the relative size of the planets in each system. They are not scaled in relation to the central star.

Curiosity Still in Cruise Mode But Approaching Mars

Transfer Orbit of the Mars Science Laboratory Closing on Mars
Image Credit: NASA / JPL-Caltech

The Mars Science Laboratory (Curiosity) is now 73 days from landing on Mars. Curiosity is due on 5 August Phoenix time (6 August UTC) in Gale Crater.

The image above shows how close the transfer orbit of Curiosity (green) is compared to the orbit of Mars (orange).

Dawn’s Rheasilvia Basin Only 1 Billion Years Old

Southern Hemisphere
Mineral Distribution in the Southern Hemisphere of the Protoplanet Dawn
Image Credit: NASA / JPLCalTech / UCLA / MPS / DLR / IDA

Young Craters

The newest release of data from the Dawn mission to Vesta shows a very young impact basin, the mineralogy of the asteroid, and suggests that Vesta is a protoplanet.

The image above shows the mineralogy of the Southern Hemisphere of Vesta. It covers only the inner crater and highland region of the Rheasilvia Basin, compared with the elevation and gravity contour maps previously released.

David O’Brien from the Planetary Science Institute in Tucson, Arizona, is a Dawn mission scientists and discussed the dating of the two giant impact craters on the Southern Hemisphere of Vesta. “The large impact basins on the moon are all quite old. The fact that the largest impact on Vesta is so young was surprising.” Scientists have concluded that the Veneneia Basin is 2 billion years old, and the Rheasilvia Basin, which overlies Veneneia, was created only 1 billion years ago.

Vesta itself was created about 4.56 billion years ago. Observations by the Dawn spacecraft in the low mapping orbit of its year-long mission has revealed the layered composition that was suspected. Like the Earth, Mars, the Moon, and Mercury (see below), Vesta differentiated in a molten state, creating a crust, mantle and iron core. This qualifies Vesta as a protoplanet. But Vesta is not quite in the dwarf planet category to which the asteroid Ceres, next on Dawn’s agenda in 2015, or Pluto, belong.

Minerals and History

Minerals exposed in deep impacts show minerals related to subsurface magma. This adds to the evidence for a differentiated protoplanet.

Minerals on the surface of Vesta are rich in iron and magnesium, similar to pyroxenes. These minerals are the same as found in certain meteorites that have fallen on the Earth.

Southern Hemisphere
Mineral Distribution in the Southern Hemisphere of the Protoplanet Dawn
Image Credit: University of Tennessee

This image above shows three minerals in meteorites from Vesta.

The three meteorites were sliced and viewed through a polarizing microscope, which makes different minerals appear in different colors.

The image on the left is basaltic eucrite, from a meteorite named QUE 97053, from Antarctica. The middle image is cumulate eucrite from a meteorite found in Moore County, North Carolina. Finally, the right hand image is from a meteorite named GRA 98108, from Antarctica, and is composed of diogenite.


Eucrites are mostly regolith minerals formed near the surface of Vesta under pressure from newer, overlying deposits.

Cumulate eucrites, however, are rare types with oriented crystals. They probably solidified in magma chambers deep within Vesta’s crust.

The crystals of diogenites are primarily magnesium based orthopyroxene, and are igneous rocks formed slowly, also deep within Vesta’s crust.

As such, these minerals are indicative of the molten nature of Vesta’s early history, and its status as a protoplanet.

Below, we have five of the smaller bodies in the Solar System: Mars, Mercury, Earth’s Moon, Ceres and Vesta. They show the progression from planet to dwarf planet to protoplanet.

All of this evidence suggests that Vesta is a protoplanet, a remnant left over from the formation of the rocky planets in the inner solar system. It was not swept up by the formation of those worlds.

Five Bodies
Five Solar System Bodies: Mars, Mercury, Earth’s Moon, Ceres and Vesta
Image Credit: NASA / JPL-CalTech / UCLA

The Dawn image gallery for Vesta is here.

Oldest Recorded Supernova Remnant

RCW 86
RCW 86 Supernova Remnant Exploded 1800 Years Ago
Image Credit: NASA / JPL-Caltech / UCLA

In 185 AD, Chinese astronomers recorded a “guest star”. 1800 years later, astronomers determined that supernova remnant RCW 86, located about 8,000 light years from Earth, was the leftovers from the explosion of that “guest star”.

Seen from Earth, the remnant is larger across than our Moon. This is two to three times larger than expected for a supernova remnant of this age. That mystery has now been solved with new data from the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer (WISE), as well as previous data from NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM-Newton Observatory. The findings have been published in the Astrophysical Journal by Brian J. Williams, et. al. Williams is an astronomer at North Carolina State University in Raleigh, North Carolina.

First, the explosion was a type 1a supernova. X-ray data from Chandra and XMM-Newton showed that the remnant contained a large proportion of iron, typical of a type 1a supernova.

Second, it seems likely that the remnant rapidly expanded into a “cavity” in space, thus greatly exceeding the usual progress of explosion material. The cavity was the result of a stellar wind blown by the late stages of the star prior to it becoming a white dwarf. This is unusual, and normally only seen in core-collapse supernovae (type 1b and 1c).

In the image above, red is associated with the dust in the blast wave of the supernova, dust in the background are yellow and green, and stars are blue.

Spacecraft Dawn and New Results from the Asteroid Vesta

Elevation (left) and gravity contour (right) of the Asteroid Vesta
Image Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA

At the annual European Geosciences Union General Assembly from 22 – 27 April 2012 in Vienna, Austria, a series of papers on Dawn’s exploration of Vesta were presented, among 4,436 oral and 9,092 poster presentations in 530 unique scientific sessions together with 157 Poster Summaries & Discussions sessions as well as 165 side events.

A list of papers on Vesta can be found here.

The image above, left, shows the topography of Vesta’s southern hemisphere with the Rheasilvia Basin and the Veneneia Basin (a quadrangle map of Vesta can be found in this previous post).

The gravitational map on the right shows the gravitational field below the basins, with the gravity component from hills and valleys removed. Red shows the strongest gravitational pull, and blue the weakest. Rheasilvia has some denser material, shown in yellow, below the central peak, while the dark blue on the right rim of the basin may indicate lighter rock, or highly fractured material.

The image below shows a portion of Vesta and some of the many pockets of bright material on the asteroid. Vesta is one of the brightest objects in the solar system, and scientists conjecture that this represents original material from the formation of Vesta. The yellow boxes hightligh some of these bright pockets.

Bright Spots
Bright Albedo on the Asteroid Vesta
Image Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / UMD

A recent press release from NASA about the European Geosciences Union meeting details additional discoveries about Vesta, including temperature ranges in and out of shadows, surface mineral patterns, ancient rocks and recent dust and the 3-D gravitational fields from interior features of the protoplanet.

Launched in 2007, Dawn began its exploration of the approximately 530-kilometer-wide asteroid in mid-2011. The spacecraft’s next assignment will be to study the dwarf planet Ceres in 2015. These two icons of the asteroid belt have been witness to much of our solar system’s history.