In the last Curiosity post the rover had undergone a fault condition. A “transient short circuit” triggered an on-board fault-protection program to halt activity on 27 February. The mission team took a few days to test and determine the cause. In the meantime a sample from a Telegraph Hill drilling was held for testing. Satisfied the problem has been cleared, the rover continues on and the sample has been delivered to the on-board laboratory.
The plan is drive Curiosity through the Artist’s Drive valley to reach higher layers of Mount Sharp.
The map was made in part from data from the HiRISE camera on the Mars Reconnaissance Orbiter.
The sun emitted a solar flare on 11 March 2015 and was captured in this excellent video by NASA and the Solar Dynamics Observatory. The flare was a powerful X2.2 class flare.
The “X” classification denotes the most intense flares. The number gives us a to gauge its relative strength compared to an X1 flare. A flare of X2 is twice the strong as an X1 and a 3 would be three times as strong. So the X2.2 classification pegs this flare as 2.2 times as strong as an X1.
The flare and not one but three coronal mass ejections (CME’s) prompted the US, Space Prediction Center (NOAA) to issue a Minor Geomagnetic Storm watch (Level G1).
The peak of the storm is expected to occur around 0100 to 0700 UTC on 13 March. Thats 2100 EDT 12 March to 0300 EDT 13 March in the US. If you want to see an aurora keep an eye on the sky around these times and please know these times are good estimates but there could be some deviation.
I should be near a computer today and will post updates as needed/available as edits to this post.
Here’s an image of the Saturn moon Iapetus from the Cassini spacecraft. It is the third largest moon of Saturn with a diameter of 1,417 km / 914 miles or about 40 percent of our moon . Iapetus has density of 1.1 so we know it is made largely of ices.
It’s a strange moon. Take note of the dark spot, that’s not a shadow. Iapetus has a dark side to it that has nothing to do whether or not it is facing the Sun. What causes the asymmetry? There are a few theories, the latest (and my new favorite) is due to ice migration in what is known as the Thermal Runaway Model.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.
NASA’s Dawn spacecraft entered an orbit around the dwarf planet Ceres.
The spacecraft was captured by the gravitational pull of Ceres at 07:39 EST / 12:39 UTC on 06 March 2015.
The confirmation came when JPL recieved a signal from Dawn that it was healthy and the ion engine was thrusting as expected.
The image above from the spacecraft was taken about the time of orbital entry at a distance of 61,000 / 38,000 miles from Ceres. I believe this will be one of the last images we will see for a short while as Dawn is on the side of Ceres away from the sun so it is too dark for imaging. The spacecraft will return to the lit side in April.
All the clues lead to the idea there was water on Mars, little dispute there. How much water there was is the question. Scientists at Goddard Space Flight Center (NASA) suggest the planet was 20 percent covered with water.
The following question has to be: was the water there long enough for life to exist?
Scientists using the W.M. Keck Observatory and Pan-STARRS1 telescopes have discovered a star that breaks a speed record. This star is traveling at 1,200 km/sec (2.7 million miles per hour). Fast enough so the star will escape the gravity of the galaxy and leave. Only a handful of such stars are known.
This star was part of a binary star system and was ejected by a supernova explosion. The image above is an artist impression and it shows the star to the left and the supernova at the same time but the supernova would have faded away by the time the star hit that position.
The hypervelocity stars are destined to spend their lives speeding through intergalactic space although it is thought usually such stars get ejected due to a close encounter with the black hole at the center of Milky Way.
While the image shown here is an artist concept, scientists observed this star called US 708 with the Echellette Spectrograph and Imager instrument on the 10-meter, Keck II telescope to measure its distance and velocity along our line of sight. By combining position measurements from the archives with new measurements from Pan-STARRS1, scientists were able to come up with the star’s velocity across our line of sight. The trajectory of the star shows the velocity cannot be from an encounter with a black hole.
US 708 has another peculiar property in marked contrast to other hypervelocity stars: it is a rapidly rotating, compact helium star likely formed by interaction with a close companion. Thus, US 708 could have originally resided in an ultra compact binary system, transferring helium to a massive white dwarf companion, ultimately triggering a thermonuclear explosion of a type Ia supernova. In this scenario, the surviving companion, i.e. US 708, was violently ejected from the disrupted binary as a result, and is now traveling with extreme velocity.
A problem has developed with the Mars Science Laboratory also known as Curiosity.
The image above shows the drill section of the rover after it finished drilling into “Telegraph Peak” on 24 February 2015. On 27 February 2015 as the sample was being transferred the sample powder obtained from the drilling process an electrical “irregularity” triggered a fault-protection event. The fault-protection event halted the process because it stopped the arm activity.
Telemetry indicates a transient short circuit occurred prompting the pre-programmed response to the anomolous condition by stopping activity; hopefully sparing the rover further damage. Mission managers are running tests and will continue to work through the problem. In all likelyhood Curiosity will be back to work soon — stay tuned.
Here’s something you don’t see very often or ever for that matter. We can see the shadow of ESA’s Rosetta spacecraft on Comet 67P/Churyumov-Gerasimenko.
During the close flybys of a couple week ago, only 6 km separated spacecraft and comet. During the flyby the sun was directly between sun and comet so a shadow of about 20 x 50 meters (66 x 164 feet) was projected onto the comet. ESA was able to capture the image with the OSIRIS camera.
The pair were about 2.35 AU from the Sun so if I did the math correctly the light levels would be approximately 5.5 times less bright than what we see around us.
Approximate brightness relative to us is about the distance in AU (astronomical units) to the power of 2,
2.35 AU 2 = 5.5 (in this case 5.5 X dimmer)
Is this a first? I can’t think of any example of shadows on other comet encounters.
ESA has a nice write up and more pictures at the Rosetta blog, check it out.