EXOMARS, Trace Gas Orbiter & Schiaparelli

The objectives of ExoMars mission is to look for life beyond earth (exo-biology) and it is performed by sending an orbiter (Trace Gas Orbiter, TGO) and Lander (Schiaparelli) which is already on its way to the Red planet and preparing for a rover in the next available celestial window in 2018. It is a joint venture between ESA and Russian space agency Roscosmos. Instead of giving a routine information on this mission, I try to bring out the niche technologies utilized by the participating European countries in TGO, which are at the forefront of Planetary Exploration. Special emphasis is made to bring out those attractive aspects of the "suite of instruments" which are employed to hunt down the elusive secrets (methane) on Mars.

Courtesy: ESA 

Trace Gas Orbiter, as the name suggests is geared to look for trace gases, these are defined as the species which fall in "less than 1% composition" of a planet. Since the signature of life could be buried with methane, a trace gas, concentrations occurring at parts per billion (10^-9) by volume; TGO carries a suite of instruments to monitor this gas primarily and many other trace gases which have been contemplated but never have been recorded at all. There is also an un-resolved issue of how the Martian atmosphere is lost; this could be accomplished by measuring ratios of isotopic species of various gaseous compounds with respect to the normal; example: HDO/H₂O. By comparing the ratios with the one appearing earth; one can estimate the loss of lighter species as compared to heavy. In summary, the task of TGO is 1. to look for methane at ppb concentration levels (huge demand on sensitivity of the instruments) and 2. measure the ratios of isotopologus species (very high spectral resolution required) and 3. technology demonstration for landing in a thin Martian atmosphere (Schiaparelli).

A brief introduction on composition of Martian atmosphere:
Major gases [Martian atmospheric pressure ~ 10 torr (Earth's: 760 torr)]

CO₂:  95%  (0.95)

N₂ : 2.7%  (0.027)

Ar : 1.6% (0.016)

Trace gases

O₂:  0.13% or 1.3X10^-2

H₂O:  2.0X10^-4

CH₄:  ~ 1.0X10^-8 or parts per billion (10^-9), (ppb)

For a composition analysing scientist measuring methane at a ppb level concentration is a million dollar ??? (or higher) question. This is where the Trace Gas Orbiter, TGO's journey to the red planet is holding huge expectations from the planetary scientists across the globe (which includes me).

There are 4-gem of instruments gear to break the technology barriers primarily geared in nailing down the elusive gas - Methane.
1. NOMAD (Nadir and Occultation for MArs Discovery)
2. ACS ( Atmospheric Chemistry Suite)
3.CaSSIS (Colour and Stereo Surface Imaging System)
4. FREND – Fine Resolution Epithermal Neutron Detector.

Each instrument's configuration and their scientific goals are nicely outlined here:

Courtesy, J.L. Vago, ESA

Both ACS and NOMAD are a set of spectrometers designed to measure a huge range of gaseous species (including isotopolagous), while CaSSIS is a color camera employed in imaging, FREND searches for H-atoms down to 1-meter looking for traces of buried water.

NOMAD:
I spent 2-days in reading the "suite of instruments" NOMAD (Nadir and Occultation for MArs Discovery) carries and almost went MAD in appreciating the abundance amount of technological prowess this suite possesses. After debating on what proportion of "technical-popular" combination; I chose to take a middle path and try to keep the information flow in perspective so that both the casual and serious reader will be interested in reading beyond this paragraph.

Courtesy : ESA
(NOMAD instrument: 1. SO, 2. LNO, 3. UVIS, 4. Electronics)

NOMAD basically covers 0.2 – 4.3µ  spectral region with a set of 3-instruments operating in 3-different modes: 
1. SO: 2.3-4.3µ (Solar Occultation)
2. LNO : in 2.3-3.8µ (Limb, Nadir and Occultation) 
3. UV-VIS channel : 200-650 nm 

The SO mode is to look at the Sun during sunrise and sunset, while Nadir is looking straight down at the planet, LNO is a combination of limb scan /nadir view/Solar occultation. The table below is taken from a very recent publication of Robert et al appearing in Planetary and Space Sciences, outlining the greater details of what all NOMAD can deliver in different modes of observations.

Robert et al., Planet.Sp.Sc., 2016

Another notable point is the ability of NOMAD in detecting methane signal is given in the above said reference. Interestingly the NOMAD in LNO mode is capable of detecting methane even at 0.018 ppb (18 ppt) concentrations; which carries much superior sensitivity than the present day instruments both on Martian surface (CURIOSITY) and in the orbit (MOM: MSM, MENCA).

ACS:
 Atmospheric Chemistry Suite is a kind of complementary, IR spectrometer again with a suite of 3- built-in instruments,covering a huge spectral region of 2.3 - 17µ  i.e. 1. NIR, 2. MIR and 3. TIRVIM.

Korablev, J.App. Remote Sensing, 2014

Just like NOMAD, ACS too has SO, Nadir and LNO observation modes explained in the above table.

The science goals of various sub-sytems are:

NIR instrument:
a. Monitoring and profiling of trace components, CO, H₂O, O₂
b. Vertical profiles of atmospheric density
c.  Sensitive search for new OH, O₂ and NO night glow

MIR instrument:
a. Vertical profiles of СО2 (atmospheric density and temp.) ; minor species like CH₄ , H₂O, СО
b. Profiling of isotopic ratios HDO/H₂O, 13CO2/CO2, CO18O/CO2

TIRVIM instrument:
a. Search/monitoring of minor constituents
b. Monitoring of atmospheric dust, and condensation clouds
c. Monitoring of the thermal state from the surface.

Most striking aspect of ACS is a huge spectral resolution (resolving power~ 50,000) it offers in the MIR region of 2.3-4.3µ. This would help in detecting the trace gas species first time ever: CH4, C2H2, H2S, HCl.  The TIRVIM region is helpful in:a. detecting trace gases, b. measurement of thermal profiles, c. aerosol properties and d. trace species: NO, N2O measurements.

CaSSIS:
The color camera's spatial coverage (swath) and resolution details are outlined here:

Courtesy: J.L. Vago, ESA

FREND:
Artist's concept of the instreumnt and similar kind of observation made are given here:

Courtesy: J.L. Vago, ESA

TGO has added huge expectations among the Planetary scientists who are looking forward to fix the jigsaw puzzle on life beyond earth and in particular signatures of life on our next neighbour.

India need Nano satellites; Future of Space Sciences

Sputnik 1 was the first human endeavour to leave mother earth (October, 1957) to be able to wander into Space. Though it was a small satellite ( ~ 83 kg), the later attempts by humans to explore space (Low Earth Orbit, LEO) were becoming increasingly bulky. The exploitation of geo-synchronous orbit (36,000 km) for beaming telecommunication and other signals could only add more burden on building huge work horses (Envisat ~ 8,000 kg). The present discussion is limited to Nano-Satellites, which fall in the 1-10 kg weight category; while Micro- satellites are in 100-10 kg and Pico satellites under 1-kg.

As the miniaturisation in electronic components (MEMS) started, so was the aerospace industry turning to COTS (Commercial, Off-the-Shelf) based small satellites. The idea was to try out newer technology riding on tiny satellites (Micro / Nano) even if the sub-components are not of very expensive MIL (military) grade, meaning radiation hardened class.  In came a "golden standard" called Cubesat, by a group of scientists lead by Bob Twiggs (Stanford Univ) and Jordi Puig-Suary (Calpoly University, California) in the year 1999. They called 1U (1-unit) which would measure 10 X 10 X 10 cm and weigh less than 1.33 kg. Same group also came up with a great idea of developing a P-POD (Poly-Pico satellite Orbiter Deployer) satellite dispenser. Their idea is to impart training for the undergrad students in the space technologies at affordable budget.

Credit : Skybox Imaging

The first Cubesat shot into space in 2003.. oh boy!! ... it transformed the land scape of how one reaches space.  The years 2014, 15 saw nearly 100-Cubesats launches each across the globe. In USA (and Europe) NASA, US-Air force ventured into Micro-satellite developmental programs. NASA's AMES centre had well laid program on Space biology, Lunar Sciences and Inter-planetary missions.  Similarly, JPL (Jet Propulsion Laboratory) too has a vibrant Cubesat program to monitor the earth and also a curious MARCO (Mars Cube One). MARCO's are two data relaying Cubesats which will be part of NASA's  next journey to Mars. They call it a "Technology Demonstration".

Observations made by Michael Swatwout at Saint Louis University, highlights the point (shown below) that the task of Nano satellites has tilted towards Technology demonstration as compared to Educational purposes. A country like India can afford to skip the FIRST step and take advantage of easily availabile components to be able to develop newer technologies.

Credit: Michael Swatwout, SLU

Nano-Satellites: Easy to make
It is not the big players for whom the tiny cubes were like TOYS, even for a lazy engineering graduate there are almost a dozen shops opened up in USA, where a stroke of key board and a credit card can bring him "Power board to Communication board even a Cubesat camera. Here are a few to quote as examples:

Credit: Cubesatkit

http://cubesatshop.com/

http://www.cubesatkit.com/

https://www.planet.com/



INDIA and Nano-Satellites
India has started venturing into space from the SLV (Satellite Launch Vehicle, 1979) Program. The first flight under the leadership of very well known face from India Dr. APJ Abdul Kalam was a failure; within a year the next flight roared into the skies of Sriharikota in southern India; that was lesson#1 in the history of ISRO; they never seem to look back in repeating failures. The PSLV (Polar Satellite Launch Vehicle) too had to face the setback in its first flight but never ever looked back till date... the present SUCCESSFUL FLIGHT number is 31 and is still counting.

As dictated by the priorities, the Indian Space Research Organisation (ISRO) has been having a very active, bright, successful program which has catapulted the country's name among the league of biggest players in world. ISRO has been successful in low earth orbit programs (IRS satellites), geo-synchronous orbit program and a very successful Lunar (Chandrayaan-I) and Martian (MOM) missions. Capturing the tag of FIRST nation to do so in its very FIRST attempt.

STUDSAT, Credit: ISAC, ISRO

However, the neglected aspect of Small Satellite activity can be gauged by noting that India could launch a meagre number of FIVE in the entire history. Among these, there are just 3-of them which are 10-kg or less. Notable is JUGNU, a 3-kg satellite, developed by Indian premier education center: Indian Institute of Kanpur (IITK). The real hero in my view is STUDSAT which was developed by a group of engineering colleges from the cities of Bangalore and Hyderabad. The reason for STUDSAT to stand out is: due to their limited resources and also a mammoth task of co-ordination among the youth... Hats - off guys...

So... as my title says.... Today, India is a vibrant country with huge potential of growing in cutting edge technologies. Nano Satellites will offer a first hand training to the youth of our nation; also as it has been noticed worldwide that these tiny toys can serve as work horses for testing the new technologies in space, before venturing with millions of investments. With ISRO as the back bone, we can do a lot better than what we have been on the Nano Satellite front..... Let's kick start this activity.... which would bolster the Make in India program as envisaged by the central government.

ASTROSAT vs The Giant Hubble

A TV program on the legendary Hubble Space Telescope, HST (Hubble's Cosmic Journey, National Geographic), prompted me to write this piece on the recently launched Indian space telescope called ASTROSAT.  The purpose of Hubble Space Telescope is to break the barrier of 1-arc second seeing limit (full moon is about 1,800 arc-seconds across) from the ground which arises due to the atmospheric disturbances. NASA had achieved this by a mammoth effort of grinding a 2.4-meter glass to the curvature accuracy of 1/800,000 th of an inch and placing the school bus size object weighing 11,110-kg in 550-km orbit. ASTROSAT is India's  multi-wavelength telescope geared to look at the stellar objects primarily in UV, X-ray regions of the EM spectrum. In that TV program, the sweet voice of John Grunsfeld conveying his strong bond he had created in repairing the Hubble more than one time. Hubble is the most sophisticated optical experiment of humans in the space which has been working for 25-years and is going great guns.

In the back drop of this legacy; enters here,  the young-aspiring Indian beauty, ASTROSAT. In a typical Indian style of small-simple but effective, this telescope carries the same heritage as that of the Indian Chandrayaan-I (moon  mission) and MOM (Mars mission).  The idea of Indian scientists is to perform front line research from the existing experience in the country (X-ray astronomy); and hence majority of the hardware which went into is in the X-ray regime of EM spectrum. Considered to be a small size (in comparison to others) space telescope, it weighs 1513-kg at the time of lift off; it is basically a multi-wavelength telescope in a near equator orbit of around 650-kms radius.

Credit: DNAINDIA 

Apart from performing the deep field survey of the Universe in the UV region; ASTROSAT's wish list covers a wide range of phenomenon which are taking place in the universe:
a. studying the high energy processes of binary star system (neutron star-black hole),
b. estimation of magnetic field of neutron stars,
c. look for star birth region beyond our galaxy,
d. detecting the new briefly appearing bright x-ray sources in the sky.

If I could drift a bit beyond the popular level flow of this presentation; here is the list of payloads, the instruments which are very well thought over and put together by the host of Indian research institutes: TIFR, IIA, IUCAA, PRL and RRI.

Credit: ISRO

The details given above emphasises that the Optical and UV region is covered by a single detector; great efforts have been put to cover a very wide range of X-ray based 4-instruments.

As they say, the proof of the pudding is in eating.... the ASTROSAT has come out with a flying colours as soon as its eyes were made to open.

On 17th November, when the Swift observatory of NASA made its 1000th observation of Gamma Ray Burst (GRB), the ASTROSAT's CTZI indeed picked the same object and hence the sweet news of success to the eagerly waiting Indian scientists. The observations are reported here .

COMPARISON: 

Comparing Hubble Telescope with the ASTROSAT would be like comparing the legend Carl Lewis to that of a young athlete or in Indian terms, comparing Sachin Tendulkar to a Ranji trophy player. Without offending anyone, I must also add that both of these sport legends have indeed followed the same nascent stages. Hubble is a huge optical telescope to peek deep into the dark patches as seen from the ground telescopes. This was possible due to the avoidance of atmospheric disturbances. Where as, ASTROSAT is a multi-wavelength observing telescope; may not be huge in size but carries a state-of-the art X-ray detectors and a combined UV-Visible detector in aiming the similar deepest in-accessible "dark regions". With the success of operation of most of the detectors, it is only the time which is going to unravel the worthiness of all the hard work of Indian scientists. Best of luck INIDA..... 

Hubble Space Telescope

As has been referred here, Hubble is a legend in opening the eyes of humanity into the darkest regions of skies. Hubble basically is an optical observatory with an viewing ability of better than 0.1-arc second, having the 3-different types of sensors: i. Camera, ii. Spectrograph and iii. Photometer. A daring 5-space walks had fixed the flaw in achieving the intended goals of Hubble imagery; a total of 4-repairing attempts have kept the instrument in its best abilities.

Here is the summary of few greatest achievements of Hubble:

• Identification of dark matter which is otherwise invisible and comprises around 23% of the entire universe could be modelled into 3-D from the observations of Hubble
• Hubble discovered 2-new moons of Pluto : Nix, Hydra
• Identification of star forming regions, e.g. Orion nebula
• Picking up gamma ray bursts (GRB) and resolving the mystery around them
• Capturing the famous collision of comet Shoemaker-Levy with planet Jupiter
• Helped to identify the dark energy which is responsible for expansion of universe
• Super massive black holes may be lurking in many galaxies that have bulge of stars at the centre
• Observing the atmosphere of exo-planet (in Visible)

The list goes on.... and is still counting.....

The humble : ASTROSAT

The unique capabilities of ASTROSAT lies in its multi-wavelength capabilities of observing stellar objects.

• The Large Area X-Ray Proportional Counter (LAXPC) stands out among all the available space telescopes (RXTE, HEXTE, SAX); by offering almost 3-times larger area at 40-keV energy x-rays.
• The LAXPC will also offer best timing studies; helping the observers to study the strong gravity regions around neutron stars and stellar mass black holes
• LAXPC will also serve  as a complimentary instrument for the present/upcoming spectroscopic observations (Chandra, XMM-Newton, NuSTAR, ASTRO-H)
• Sensitive hard X-ray spectroscopy
• Wide spectral coverage : UV, 0.3-150 keV

RXTE : The Rossi X-ray Timing Explorer
HEXTE : High Energy Timing Experiment
SAX: Beppo SAX, Italian Dutch Satellite for X-ray astronomy
MOM: Mars Orbiter Mission

Water on Mars

After the discovery of bone dry moon to be holding traces of water molecules... Water on Mars means a lot to the human race. It is not a meagre scientific result where a 9-year old space craft revolving around Mars and 4-years old results have shown liquid water to be flowing during the summer on Mars; rather, these results have re-kindled new hopes of finding life on Mars, as per Michael Meyer, NASA's Mars Exploration Program. Of course, the intelligent, eager and inquisitive human's quest of leaving earth has found astronomical levels of adrenaline pumping into their blood streams.

This is the picture released by NASA which speaks tonnes of words on how the newly appearing streaks, called the recurring slope lineae (RSL)... held the secrets under their belly for so long that it took a smart under graduate student, Lujendra Ojha from Georgia Tech to figure out that these are actually hydrated salts which appear only when the ambiance reaches -23 C and above. In a way, the salts are helping the ice (water) to melt at much much lower temperatures; just as salt on roads here on Earth causes ice and snow to melt more rapidly.

Credit : NASA

SECRETS unravelled..

The dark streaks seem to be appearing in the summer and would again vanish as the temperature dips. It is only due to the long lasting mission Mars Reconnaissance Orbiter (MRO) and the versatile instruments it is carrying; that the keen observations of this undergrad student along with his team members that they found a way to unravel the secret beneath these streaks.

Ojha and his team first created a 3-D model (digital terrain map) utilizing the stereo information from  High Resolution Imaging Experiment (HiRISE) camera of MRO. The image is draped with the spectral information from Compact Reconnaissance Imaging Spectrometer (CRISM) of MRO. The spectrometer component of the overlaid image shows information about the hydrated salts at the multiple RSLs.

Ojha and his co-authors interpret the spectral signatures as caused by hydrated minerals called perchlorates. The hydrated salts most consistent with the chemical signatures are likely a mixture of magnesium perchlorate, magnesium chlorate and sodium perchlorate. This study of RSL detected perchlorates, now in hydrated form. This also is the first time perchlorates have been identified from orbit.

Another example of Dark Streaks on Garni crater..

Credit: NASA

Breakthrough Listen - Search for Aliens

"Is there an intelligent life beyond Earth? " this question has been bothering the human race as far as 19th century. The Serbian-American Scientist Nikola Tesla proposed to send signals to Martians (1890); he claimed to have received unusual signals, calling them to be from "another world". The project, Search for Extra Terrestrial Intelligence, SETI, 1960 by Frank Drake, USA was to look for radio signals sent out by intelligent life in the universe.

The declaration of 100-million dollars fund by the Russian investor Yuri Milner with a surprise addition of Stephen Hawking in his team, the project "Breakthrough Initiatives" would certainly change the fate of SETI search. Milner, a physics graduate turned investor is known for turning coal into gold, with his investments bringing a new tide into the businesses (e.g. facebook, twitter, alibaba, xiomi, flipkart....); lets hope the same for SETI.

Credit: www.effmeride.it 

How is it done??
First strategy: Search for the radio signals in the nearby 100 million stars hoping that civilization living in their planetary system may be intelligent enough to have a radio active utility in their routine works, e.g. air traffic control or any other communications.

Since the past studies of SETI have strongly suggested that the radio signals from extra-terrestrial signals could come only from the far away sources and they could be extremely strong, an alternative hunt would also be planned.

Second strategy: Here the entire plane of milky-way galaxy (where we live) and the central zone will be studied in detail to cover more than 100-billion stars in the shallow region (meaning far away). Apart from this, the survey would also stare at 100-galaxies  comprising of 10s of trillions (1000-billion or million-million) of stars, each star having its own planetary system.

To accomplish the above said goals; the plan is to spend one-third of the funding in buying 20% of the 100-meter diameter Green Bank radio telescope at West Virginia and a substantial amount of time on Parkes 64-meter telescope in Australia for 10-years.

100-meter Green Bank radio telescope

Another one-third amount of funds are planned to develop very high sensitive receivers to listen to billions of narrow frequency channels in 1-10 GHz, a  region which covers best of the radio signal regimes which passes through the earth's atmosphere and also clean from the cosmic background . 

Breakthrough Listen will also be taking up observations in visible light region on the 2.4-meter Lick observatory's  planetary finder telescope. This would serve as an additional tool to support and confirm the region from where one hopes to pick POSITIVE signs of civilization.

Example: As per a rough estimate, the present studies (at Green Park) can pick up signals: "If an alien civilization living on a planet orbiting around any of the 1000 stars closest to us from a common air traffic kind of communication signals". 2. The optical signals monitored at Licks observatory would be able to pick 100-watts of light from the planets of stars which are within 4-light years away from ours.

Prominent SETI attempts:
A British radio astronomer, Antony Hewish and his post doc Jocelyn Bell studying the inter planetary scintillations of compact radio sources came across a set of radio sources displaying very regular and fast packet of signals. Unable to identify the source they went on to name them "little green men". Later the team went on to discover a new set sources called Pulsars; Anotny Hewish getting a noble prize (1974) for this discovery.

The famous ISRO-Balloon experiment, where the Indian scientists lead by Dr. Jayant Narlikar have successfully found bacteria in the stratosphere of earth, at an altitude of 20-40 kms. The three group of bacteria to be identified after the gene sequencing technique have been found for the first time (Reference). Though the Indian experiment may not fall under the LISTEN category, it does stand out as an outstanding effort of humans to reach out extra terrestrial life. India can certainly play a big role in this project; Milner goes on record to say that the idea of pumping this money is to instigate young minds towards science... is any body listening????

Bottom line!!
Though the present initiative may increase the SETI search by 100-times in the form of more sensitive tools (a rough estimate); it may take even generations to get to listen to the super civilization living away from our world. But surely enough... Milner has certainly initiated a giant step towards SETI...


Credit: 
Like to give credit to few press reports appearing in the internet after the declaration of Breakthrough Initiatives project on 20th July at the Royal Society, London, particularly to a good piece of article appearing in the Sky and Telescope by Alan MacRobert.

NEW HORIZONS

Key words: New Horizons, Alan Stern

The NASA page of New Horizons says.... 10-Years..,5- Billion kms; truly the human aspirations are racing towards the edge of solar system with an astounding speeds of 80,000 km/hour. To be able to reach Pluto, the New Horizons space craft has to take a slingshot from the giant planet Jupiter. The scientists are going to peek into the new frozen world of Pluto on 14th July 2015 at a distance of just around 12,500 kms having to view football size images with 48-meter resolution. Where as, after its discovery in 1930, Pluto has just been a dot to the best possible astronomical observations from earth, except for few (10-12) pixel across image appearing in the Hubble Space Telescope in 90s. Why are the scientists so excited???  they say.... they have no idea.. may be it is the thickest atmosphere or gaseous jets streaming out.... anything.... so little is known.

New Horizons, Credit : NASA, 

New Horizons (NH).. an unique attempt?
Voyager-1 (Sept-1977) which has crossed the solar system now, had opted for Titan (Saturn's moon) as a compromise to bypass Pluto's flyby. Voyager-2 (Aug-1977) never had a trajectory to flyby Pluto. Then comes... New Horizons (2006)... fully geared to explore this dark world at its gory details. NH got the best opportunity to catch up with the celestial windows to be able to sling shot towards Pluto before the planet drifts further away and the atmosphere it holds getting frozen. As per the inspirational posts from Alan Stern, PI, that every care has been taken to avoid any collision the space craft may suffer due to the un known world around Pluto. "It was a relentless effort of around 2,500 NASA employees's effort that is going take us into these unknown worlds" says Alan Stern.

The Space craft:

To quote NASA, the piano sized space craft weighs 478 kilograms, with the lead role taken by the Southwest Research Institute, APL-JHU and contributions coming from (GSFC, JPL, KSFC, UC, Stanford...) many other institutions, to say a typical American heritage. Its a technological marvel running on a single radio-isotope thermoelectric generator of 200W capacity provided by a 11-kg Plutonium dioxide. Most of the instruments working at an average power of 5W (~ night lamp) and with the data being transmitted via 2.1-m antenna, a must for an object 5-billion kms away and the communication taking almost 9+ hours both ways. 

Instruments, Credit: NASA

Instruments:
The 7-instruments are like gems, hand picked with 10s of deliberations carried to get the maximum from the un-known worlds. In my priority list:
1. LORRI, the telescope/camera comes first. Dubbed as the hawk eyes of New Horizons, it is basically a black and white digital camera with a 20-cm telescope, but built to work in a hostile cold environment. On 14th July, LORRI will be beaming football size images with an unprecedented 50-meter resolution, a life time opportunity for all the planetary scientists. 
2. RALPH, though called as the "main eye", but a complex mixture of instruments comprising of three panchromatic imagers, four color imagers and a spectrograph. It will offer an abundance information on surface geology, morphology and thermal features.
3. ALICE is an imaging UV spectrometer to study the composition of Pluto's atmosphere. A smart baby with a built-in telescope and a huge spectral coverage to study ionic to neutral species.
4. REX, a smart idea of employing occultation technique (looking down to earth's DSN signals via the target atmospheres) to measure pressure, temperature of atmospheres of Pluot and Charon.
5. SWAP, to measure solar wind around Pluto, 6. PEPSSI to look for energetic particles, last but not the least 7. SDC a student dust counter, developed by the students to measure microscopic dust grains produced by the collision among asteroids, comets and KBOs.

Pluto Picture of the Day..... (updated daily...)

Mountain range discovered by NH on 14th July in the Tombough region from a distance of 77,000 km Credit: NASA.

Another secret of Pluto revealed, as NH was moving past Pluto, it captured the haze around Pluto extending to 130 km. Credit: NASA.

Philae vs. MIP (Moon Impact Probe)

Key words: Philae, Rosetta, Moon Impact Probe, Chandrayaan-I

Today (14th Nov., 2014), exactly six years ago "the messenger from India" (as president Kalam called it) Moon Impact Probe had crash landed near Shackleton crater, very close to the south pole of the moon. While 2-days ago we hear about Philae probe of Rosetta space craft of ESA landing on the Comet P67 and hence the title of this post; by no mean there could be any other analogy in these missions. Let me narrate few amazing facts about Philae then will switch over to my own personal experiences as a core-science team member of Moon Impact Probe mission in Chandrayaan-I.

Philae:

Credit : ESA

The team of Rosetta waited for almost 10-years in chasing the P67 comet before they could send 100-kg Philae to set its foot on the tiny nucleus which was measuring just around 4-km. The mind boggling numbers of 500-million km journey lasting 10-years and sailing along side the elusive comet's nucleus at a distance of few-100s of kms  with a speed of 64,000 km/hr were all truly hair raising statements.

On 12th Novemeber, 2014, the time had just been ripe for the team Rosetta to fire the Philae weighing 100-kgs and would take around 8-hours to be ready to land on the nucleus. As it reaches the nucleus of the Comet, Philae would fire 2-harpoons and would tag itself onto the soft surface. The press reports (from ESA officials) confirm that the Philae has in fact bounced twice and later got settled at location which is not known for sure as of today (14th Nov., 2014); however finds itself in a shadow of a cliff shown below.

Credit: ESA

Though the fully charged battery of Philae would permit its 9-instruments to operate for 56-hours; but the recharging would take much longer than the expected time as the present location would offer only an hour of sunlight for the solar panels to charge the battery; this is certainly not the dead end, as the comet itself would offer its "seasons" where the same location could hope to get much more sun exposure in the future. It is indeed a moment of pride for the entire humanity that the ESA has achieved for the first time on being on a comet. The scientists are upbeat about Philae (though landing on 2-legs, out of three) being very healthy as far as running of their proposed battery of experiments are concerned. Any further manoeuvrability need to be done with extreme care as this may lead to dislodging of the probe from the surface itself. Why... because the the 100-kg Philae would weigh just around 1-gram due to a reduction of gravitational pull of P67 of the order of 100000 less as compared to earth.


Moon Impact Probe (MIP):

Mission: While Phiale's mission is just like a scene picked from a Hollywood movie; Moon Impact Probe was a hard work of a small group of scientists from southern tip of India and their aim was ONLY to drop a 30-kg mass on the southern tip of moon. The mother space craft (red), Chandrayaan-I would re-orient to accommodate MIP separation. During this time the MIP (green) would be detached and in a "pre-programmed" sequence would fire de-orbit motor to reduce the forward velocity component while a set of thrusters fitted on the side would spin-up the probe to attain a stable descent journey. The selected target was close to the Malapert Mountain near the south pole of the moon.

MIP mission; Credit: ISRO

The MIP mission as it was called in the Chandrayaan-I project was the brain child of President Kalam, as per his vision "let there be a messenger reaching moon from the Indian soil". This idea was to be realised at ISRO's Vikram Sarabha Space Center, VSSC. Traditionally at ISRO's VSSC; it has been the hub of developing and realising the rockets, while the idea of MIP which comprises of an autonomous power, communication and instruments can almost be treated as a stand alone space craft. This was a unique experience for the entire group of MIP developers. The objective of MIP was a "Technology Demonstration" which means all other issues (science) would take a back seat; however, the development of a science instrument (CHACE) in this mission with its members having least amount of experience were entertained by the core group of scientists; which allowed us to pull-off one of the most sensitive instrument (CHACE) to study the nearest heavenly body. The plan: the MIP a cuboid of 1/2-meter size weighing around 30-kg would be detached from the mother space craft in the very first opportunity of Chandrayaan-I achieving its 100-km polar orbit.

Moon Impact Probe; Credit : VSSC-ISRO

The MIP would carry 3-experiments during its approximate 22-minutes descend journey. 1. CHACE, (link) the mass spectrometer would sample the nearby ambiance in 1-100 atomic mass range, 2. Color Camera would take pictures and 3. Radar altimeter would measure the distance from the lunar ground. Details of CHACE are narrated here.

It was on 14th November, 2008 around 8.22 pm IST that we were all waiting for the confirmatory signal from MIP which would actually cease to exist (meaning "die down"). It indeed happened and the sacrifice of MIP (that is crash landing) has brought immense wealth of data. The color camera sent stunning pictures as MIP was descending; while CHACE spectrometer measured almost a dozen gaseous species with the peak at 18 representing water standing very very tall indicating the presence of water unambiguously.

MIP landing; Credit : SAC, ISRO

It was no ordinary feat for the MIP team members to design and develop a probe from scratch in a span of just around 4-years and achieve an amazing piece of success in the form of landing the probe within 2-kms of intended location.