NEW Ten things you need to know about our solar system this week

Ten things you need to know about our solar system this week

1. What's Up?

The reliable Perseid meteor shower arrives mid-August. Credit: NASA/JPL-Caltech

Welcome to August, skywatchers. There are plenty of sights to anticipate this month, including five planets after sunset and one of the best meteor showers of the year.

+ Find out what to look for

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2. Farewell, Philae 

Reconstruction of Philae's flight. Credit: ESA

After a successful and eventful adventure landing on a comet, no more signals will be received from the Rosetta mission's comet lander, Philae, according to the European Space Agency (ESA). Thank you, little craft, and congratulations on earning your place among the great comet expeditions.

+ Learn more
+ Send your own goodbye to Philae
+ Find out about the dramatic upcoming end to the Rosetta comet mission

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3. Bringing the Heat

Artist's representation of the Great Red Spot heating the atmosphere. Credit: Art by Karen Teramura, UH IfA with James O'Donoghue and Luke Moore

New NASA-funded research suggests that Jupiter's Great Red Spot may be the mysterious heat source behind Jupiter's surprisingly high upper atmospheric temperatures. When the Juno mission begins its science orbits in the coming weeks, the Great Red Spot will be among its top targets.

+ Get the details
+ Check in with Juno

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4. Cut and Dried

When the gullies are observed with the addition of mineralogical information (color), no evidence for alteration by water appears. Credit: NASA/JPL-Caltech

New findings using data from NASA's Mars Reconnaissance Orbiter show that gullies on modern Mars are probably not cut by flowing liquid water, as some researchers had suggested, but rather by processes such as the freeze and thaw of carbon dioxide frost. (Note that gullies are distinct from another type of feature on Martian slopes, the streaks called "recurring slope lineae," where water in the form of hydrated salt has been identified.)

+ Learn more

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5. Lock on Target

Credit: Jean-Luc Lacour

It was always a very clever robot, but now NASA's Mars rover Curiosity can even choose its own rock targets for its laser spectrometer. Using new software, the mechanical geologist automatically selects several targets every week for the laser and telescopic camera that make up the rover's ChemCam instrument.

+ Find out how firing a laser helps scientists take aim at discoveries on Mars

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6. A Flair (and a Flare) for the Dramatic 

Credit: NASA/SDO

The sun recently emitted three mid-size solar flares, and NASA's Solar Dynamics Observatory, which watches the sun constantly, captured it all. Solar flares are powerful bursts of radiation, and while harmful radiation from a flare doesn't pass through Earth's atmosphere to physically affect humans on the ground, flares can sometimes disrupt GPS and communications signals.

+ Watch the show

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7. The Case of the Missing Craters

Credit: NASA/JPL-Caltech

Ceres is covered in countless small, young craters, but no really big ones. This is a mystery, given that the dwarf planet must have been hit by numerous large asteroids during its 4.5 billion-year lifetime. Where did all the large craters go? A new study explores this puzzle using data from the Dawn mission.

+ See what scientists have figured out so far

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New Horizons Principal Investigator Alan Stern celebrates a Guinness World Record certificate on July 19 at U.S. Postal Service Headquarters in Washington, D.C. Credits: Dan Afzal, U.S. Postal Service

8. Long-Distance Delivery

The US Postal Service recently commemorated Pluto and the New Horizons mission with their own postage stamps, but that wasn't the end of the mission's philatelic glory. Aboard the spacecraft is a 1991 "Pluto Not Yet Explored" stamp that's earned a Guinness World Record honor for the farthest distance traveled by a postage stamp (Pluto is more than 3.2 billion miles away). What's more, this is a record that New Horizons breaks anew every second that goes by, since it's flying ever deeper into space. Its new destination is the Kuiper Belt object known as 2014 MU69, one of the early building blocks of the solar system.

+ See the stamp and learn more about the ultimate postal route

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9. What Lies Beneath 

Venus cloud tops. Credit: ESA/MPS/DLR/IDA

Using observations from ESA's Venus Express satellite, scientists have shown for the first time how weather patterns seen in Venus' thick cloud layers are directly linked to the topography of the surface below. In other words, rather than acting as a barrier to our observations, Venus' clouds may offer insight into what happens beneath their cloak.

+ Take a deeper look

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10. Super Vision

Testing the OVIRS spectometer instrument. Credit: NASA/GSFC

NASA's audacious OSIRIS-REx mission will physically bring a bit of the asteroid Bennu to Earth. But it will map the asteroid—and even discover which minerals exist on its surface—before it ever makes contact.

See previous editions of 10 Things.