Tag: Pluto

Engineers have decided to keep the New Horizons spacecraft on its original fly-by path past Pluto, scheduled for July 2015.

11:37 am

Engineers have decided to keep the New Horizons spacecraft on its original fly-by path past Pluto, scheduled for July 2015.

The New Horizons team recently completed an 18-month study of potential impact hazards – mostly dust created by objects hitting Pluto’s small satellites – the spacecraft would face as it speeds some 30,000 miles per hour (more than 48,000 kilometers per hour) past Pluto in July 2015. The team estimated that the probability of a mission-ending dust impact was less than 0.3 percent if the spacecraft followed the current baseline plan, far below some early, more conservative estimates. So, with the concurrence of an independent review panel and NASA, the project team expects to keep New Horizons on this baseline course, which includes a close approach of about 12,500 kilometers (nearly 7,800 miles) from the surface of Pluto.

Leave a comment

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons.

1:40 pm

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons. Key quote:

Vulcan was a late addition to the Pluto moon name contenders, and pulled into the lead after Shatner, building on his Capt. James T. Kirk persona, plugged the name on Twitter. Vulcan, the home planet of Kirk’s alien-human hybrid first officer Spock, is not just a fictional world in the Star Trek universe. It is also the name of the god of fire in Roman mythology, and officials at SETI added the sci-fi favorite to the ballot for that reason.

6 comments

William Shatner proposes naming Pluto’s two unnamed moons Romulus and Vulcan.

2:52 pm

William Shatner proposes naming Pluto’s two unnamed moons Romulus and Vulcan.

Astronomers running the Pluto moon naming campaign accepted Vulcan, adding it to the list a day after Shatner suggested it, but Romulus didn’t make the cut. “Mr. Shatner’s second suggestion, Romulus, has a bit of a problem because it is already the name of a moon,” Mark Showalter, an astronomer involved with the competition, wrote in a blog on the Pluto Rocks website on Tuesday. “Romulus, along with his brother Remus, are the names of the moons of the asteroid 87 Silvia. They were discovered by a team led by my good colleague Franck Marchis, now a senior scientist at the SETI Institute.”

2 comments

The science team for New Horizons is considering shifting the spacecraft’s Pluto flyby away from the planet to avoid orbital debris.

9:20 am

The science team for New Horizons is considering shifting the spacecraft’s Pluto flyby away from the planet to avoid orbital debris.

“We’ve found more and more moons orbiting near Pluto — the count is now up to five,” Stern said. “And we’ve come to appreciate that those moons, as well as others not yet discovered, act as debris generators populating the Pluto system with shards from collisions between those moons and small Kuiper Belt objects.”

Leave a comment

New Horizons — on its way to Pluto — will take a look at a different Kuiper Belt object in January 2015.

2:46 pm

New Horizons — on its way to Pluto — will take a look at a different Kuiper Belt object in January 2015.

The encounter will take place at a range of about 75 million km, a distance somewhat subject to change depending on how the probe makes its course correction. At such a great distance, New Horizons will not be able to discern features on the surface of the KBO, nor will it be able to make spectroscopic observations to try to determine the composition of the surface material.

However, New Horizons will be in an excellent position to look for small, close-in moons around the object. It will also be in a position to observe the object’s phase curve, which is a measure of how the reflectivity of the surface changes as a function of viewing angle. This will reveal a great deal about the fluffiness of the surface material (note – fluffiness is a technical term meaning, roughly, “the opposite of dense”). These two observations cannot be made from Earth, even with the most powerful telescopes available.

Leave a comment

Pluto’s atmosphere is expanding, and scientists don’t know why

5:59 pm

Pluto’s atmosphere is expanding, and scientists don’t know why.

Pluto travels along a highly elliptical path and last passed closest to the sun in 1989. Many planetary scientists expected the atmosphere to shrink as the icy orb began receding from the sun’s warmth. The unanticipated expansion may be related to changes in the darkness of the orb’s surface a decade or so ago, which may have caused the surface ices to absorb more solar radiation and more efficiently evaporate. Or, Greaves suggests, long-term variations in the sun’s ultraviolet output, changes linked to the roughly 11-year cycle of solar activity, may be playing a role.

Leave a comment

When is an Asteroid Not an Asteroid?

10:32 pm

When is an asteroid not an asteroid?

The layered structure of Vesta (core, mantle and crust) is the key trait that makes Vesta more like planets such as Earth, Venus and Mars than the other asteroids, McCord said. Like the planets, Vesta had sufficient radioactive material inside when it coalesced, releasing heat that melted rock and enabled lighter layers to float to the outside. Scientists call this process differentiation.

This question immediately demonstrates once again the terrible mess the International Astronautical Union made when it decided several years ago to define what makes a planet, and came up with a definition that simply doesn’t work. For if Vesta should be considered a planet, why not Pluto?

One comment

Pluto’s ice: 97% nitrogen, 3% methane

4:00 pm

More results from the press conference going on right now at the 42nd meeting of the AAS Division for Planetary Sciences:

Pluto’s surface ice is made up of 97% nitrogen, 3% methane, while the surface of the Kuiper Belt object Eris (which is larger than Pluto) is even more rich in methane, with a make up of 90% nitrogen and 10% methane. Both measurements go down to a depth of about 10 inches. To see the abstract for this result, go here.

One comment
1 … 3 4 5