Dawn at Ceres: Safe mode recovery + White spots may be salt

While the attention of space fans is riveted on Pluto this week, another dwarf planet continues to tease the world with its peculiar features: The weird white spots on Ceres might not be ice after all – The Washington Post.

New Horizons had a Safe Mode incident last week and so did Dawn and it recovered as well:

Dawn Holding in Second Mapping Orbit

NASA’s Dawn spacecraft is healthy and stable, after experiencing an anomaly in the system that controls its orientation. It is still in its second mapping orbit 2,700 miles (4,400 kilometers) above dwarf planet Ceres.

On June 30, shortly after turning on its ion engine to begin the gradual spiral down to the next mapping orbit, its protective software detected the anomaly. Dawn responded as designed by stopping all activities (including thrusting), reconfiguring its systems to safe mode and transmitting a radio signal to request further instructions. On July 1 and 2, engineers made configuration changes needed to return the spacecraft to its normal operating mode. The spacecraft is out of safe mode, using the main antenna to communicate with Earth.

Dawn will remain at its current orbital altitude until the operations team has completed an analysis of what occurred and has updated the flight plan.

Because of the versatility of Dawn’s ion propulsion system and the flexibility of the mission’s plan for exploring Ceres, there is no special “window” for starting or completing the spiral to the third mapping orbit. The plans for the third and fourth mapping orbits can be shifted to new dates without significant changes in objectives or productivity.

More information on the Dawn mission is online at:

 

New Horizons: Misc. resources, websites, etc.

The next few days will be extremely busy and exciting for the New Horizons team. However, images and data from the closest approach on Tuesday won’t start being transmitted back to earth till  Wednesday. The probe must focus all its attention on the planet during the fly-by.

You can follow the latest news flashes about the encounter at #PlutoFlyby hashtag on Twitter.

Find lots of information and news on the mission at New Horizons, the primary website for the mission. The site includes

Here are various news sites devoted to the Pluto fly-by:

The scientific principle investigator Alan Stern is interviewed: Question time with Alan Stern, the Pluto evangelist – Spaceflight Now

Update: Here is today’s briefing –

 

New Horizons: Latest image shows lines and large dark areas on Pluto

The latest New Horizons image of Pluto shows intriguing lines and polygonal shapes on the side of the planet that will be facing away from the probe when it makes its closest approach on Tuesday (July.14):

New Horizons’ Last Portrait of Pluto’s Puzzling Spots

Three billion miles from Earth and just two and a half million miles from Pluto, NASA’s New Horizons spacecraft has taken its best image of four dark spots that continue to captivate.

nh-pluto-7-11-15[1]

New Horizons’ Last Portrait of Pluto’s Puzzling Spots – July 11, 2015: New Horizons’ last look at Pluto’s Charon-facing hemisphere reveals intriguing geologic details that are of keen interest to mission scientists. This image, taken early the morning of July 11, 2015, shows newly-resolved linear features above the equatorial region that intersect, suggestive of polygonal shapes. This image was captured when the spacecraft was 2.5 million miles (4 million kilometers) from Pluto.

The spots appear on the side of Pluto that always faces its largest moon, Charon—the face that will be invisible to New Horizons when the spacecraft makes its close flyby the morning of July 14. New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, describes this image as “the last, best look that anyone will have of Pluto’s far side for decades to come.”

The spots are connected to a dark belt that circles Pluto’s equatorial region. What continues to pique the interest of scientists is their similar size and even spacing. “It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington.  Jeff Moore of NASA’s Ames Research Center, Mountain View, California, is equally intrigued. “We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface.”

The large dark areas are now estimated to be 300 miles (480 kilometers) across, an area roughly the size of the state of Missouri.  In comparison with earlier images, we now see that the dark areas are more complex than they initially appeared, while the boundaries between the dark and bright terrains are irregular and sharply defined.

In addition to solving the mystery of the spots, the New Horizons Geology, Geophysics and Imaging team is interested in identifying other surface features such as impact craters, formed when smaller objects struck the dwarf planet. Moore notes, “When we combine images like this of the far side with composition and color data the spacecraft has already acquired but not yet sent to Earth, we expect to be able to read the history of this face of Pluto.”

When New Horizons makes its closest approach to Pluto in just three days, it will focus on the opposing or “encounter hemisphere” of the dwarf planet. On the morning of July 14, New Horizons will pass about 7,800 miles (12,500 kilometers) from the face with a large heart-shaped feature that’s captured the imagination of people around the world.

At 7:49 AM EDT on Tuesday, July 14 New Horizons will zip past Pluto at 30,800 miles per hour (49,600 kilometers per hour), with a suite of seven science instruments busily gathering data. The mission will complete the initial reconnaissance of the solar system with the first-ever look at the icy dwarf planet.

Follow the path of the spacecraft in coming days in real time with a visualization of the actual trajectory data, using NASA’s online Eyes on Pluto.

Stay in touch with the New Horizons mission with #PlutoFlyby and on Facebook at: www.facebook.com/new.horizons1

Video: TMRO 8.21 – Moon first or Mars first?

The latest TMRO.tv live program is in the online archive: Moon first or Mars first? – TMRO

In this live episode we ask you, should humanity start cosmic colonization with the Moon first or go straight to Mars first? Would love your thoughts below!

TMRO Live is a crowd funded show. If you like this episode consider contributing to help us to continue to improve. Head over to http://www.patreon.com/tmro for information, goals and reward levels. Don’t forget to check out our daily Space Pod campaign as well over at http://www.patreon.com/spacepod

New Horizons: Pluto by Moonlight + Images + Videos: Daily briefing + History + In Focus

Here are several items related to the New Horizons Pluto fly-by mission:

Pluto by Moonlight – An article about the dark south polar region of Pluto

Image converted using ifftoany
In this artist’s rendering, Pluto’s largest moon Charon rises over the frozen surface of Pluto, casting a faint silvery luminescence across the distant planetary landscape.

New Horizons SOC – gallery of images from the New Horizons probe.

* July 11th Daily Briefing:

How Pluto Was Discovered – Space Pod 07/10/15

The Ninth: Pluto in Focus – New Horizons – A short film about the mission sponsored by the Stanford Space Initiative