Falcon 9 rocket Current Affairs

GRACE-FO satellites: SpaceX launches NASA satellites to track Earth’s water Cycle

Elon Musk-led SpaceX has successfully launched twin NASA satellites GRACE-FO (Follow-On) that will track Earth’s water Cycle i.e. water movement and icemelt. It was launched onbaord of SpaceX’s preflown Falcon 9 Rocket from Vandenberg Air Force Base in California, US.

GRACE-FO (Gravity Recovery and Climate Experiment Follow-On)

GRACE-FO is joint project between National Aeronautics and Space Administration (NASA) and German Research Center for Geosciences (GFZ). It is follow-on mission to original GRACE mission, which had mapped Earth’s water and ice by measuring changes in Earth’s gravity field from 2002 to 2017.

GRACE-FO will pick up where GRACE left off to continue study of rising sea levels, melting of glaciers and polar ice caps and other changes in distribution of water on Earth. The two GRACE-FO satellites will orbit together at 490km altitude near-polar orbit, circling Earth every 90 minutes.

To measure Earth’s gravity, two satellites will orbit around Earth together, with one trailing behind other at distance of 220km. The instruments on board of these satellites are so sensitive that they can detect changes with precision of about 1 micrometer (i.e. about one-tenth of a human hair over long distance).

These satellites have payload called Laser Ranging Interferometer. It can precisely measure gravity field changes due to change in separation distance between two satellites, revealing information about what kinds of features they are flying over. Earth is not perfect sphere) different features, like mountains and oceans, across its surface, so gravitational pull exerted on these satellites is not consistent. When gravity field changes, separation between two satellites changes slightly.


TESS: NASA launches its newest planet-hunting spacecraft on SpaceX rocket

The National Aeronautics and Space Administration (NASA) launched Transiting Exoplanet Survey Satellite (TESS), a new planet-hunting spacecraft onboard of SpaceX’s Falcon 9 rocket from Cape Carnival, Florida, US. TESS mission is designed to carry out first spaceborne all-sky transiting exoplanet survey.

Transiting Exoplanet Survey Satellite (TESS)

The TESS mission is led by Massachusetts Institute of Technology’s Kavli Institute for Astrophysics and Space Research. It is designed to find potential planets orbiting stars close to Earth. It will identify such planets by spotting decreased brightness of stars after planet passes in front of it.

The primary mission objective of TESS is to survey brightest stars near Earth for transiting exoplanets over two-year period. It will use array of wide-field cameras to perform all-sky survey. It will create catalog of thousands of exoplanet candidates using transit photometry method.

TESS observatory weighs just 362 kilograms. It has four wide-view cameras surrounded by sun shade to monitor any dips in brightness from target stars. Repeated dips will indicate a planet passing in front of its star. TESS has no instruments capable of detecting life. Its main job is to find and characterize planets that will become main targets of future telescopes.

With help of TESS, it will be possible to study mass, size, density and orbit of large cohort of small planets, including sample of rocky worlds in habitable zones (goldilocks zone) of their host stars. This will reveal whether planets are rocky (like Earth), gas or jovian giants (like Jupiter) or something even more unusual.