Lagrange points tagged posts

Using observations made with the Gran Telescopio Canarias (GTC) a study led from the Instituto de Astrofísica de Canarias (IAC) and the Universidad Complutense de Madrid (UCM) has confirmed that the asteroid 2023 FW14, discovered last year, is accompanying the red planet in its journey round the sun, ahead of Mars and in the same orbit.

With this new member, the group of Trojans that accompany Mars has increased in number to 17. But it shows differences in its orbit and chemical composition which may indicate that it is a captured asteroid, of a primitive type. The results are published in Astronomy & Astrophysics.

A team from the Instituto de Astrofísica de Canarias (IAC) and the Universida...

Left: The paths traced by the known Martian Trojans around L4 or L5 (crosses) relative to Mars (red disk) and the Sun (yellow disk). The dotted circle indicates the average Sun-Mars distance. Right: Enlargement of inset (dashed rectangle) showing the paths of the 8 L5 Trojans: 1998 VF31 (marked as “VF31” – blue), Eureka (red) and the 6 objects identified as family members (amber). The filled disks indicate the relative sizes of the asteroids. Eureka, the largest member, is about 2 km across. Credit: Apostolos Christou

Mars shares its orbit with the Trojans, a handful of small asteroids. Now an international team using the Very Large Telescope have found that most of these objects share a common composition; they are likely the remains of a mini-planet destroyed by a collision long ago...

Illustration shows how a robot could assemble the trusses that would support a massive telescope mirror. Credit: Sergio Pellegrino/Caltech

Seeing deep into space requires large telescopes. The larger the telescope, the more light it collects, and the sharper the image it provides. Eg, NASA’s Kepler space observatory, with a mirror diameter of <1 meter, is searching for exoplanets orbiting stars up to 3,000 light-years away. By contrast, the Hubble Space Telescope, with a 2.4-meter mirror, has studied stars more than 10 billion light-years away.

Now Caltech’s Sergio Pellegrino and colleagues are proposing a space observatory that would have a primary mirror with a diameter of 100 meters – 40 times larger than Hubble’s...

The most successful technique for finding planets beyond our solar system so far is transit photometry, which measures changes in a star’s brightness caused by a mini-eclipse. When a planet crosses in front of its star along our line of sight, it blocks some of the star’s light. If the dimming lasts for a set amount of time and occurs at regular intervals, it likely means an exoplanet is passing in front of, or transiting, the star once every orbital period.

NASA’s Kepler Space Telescope has used this technique to become the most successful planet-hunting spacecraft to date, with more than a thousand established discoveries and many more awaiting confirmation...